The Present of Peripheral Nerve Regeneration / 대한정형외과학회잡지

Substantial progress has been made in peripheral nerve surgery, owing to the advances in pathophysiological understanding, microsurgical techniques and the improvement of synthetic materials. Despite this, large gaps caused by trauma, tumor resection and congenital deformities show unsatisfactory results. While primary direct end-to-end tension-free nerve repair remains as the gold standard for surgical treatment, an autologous nerve graft is recommended for nerve gaps greater than 2 to 3 cm. Studies cite remarkable clinical reports with decellularized nerve allografts after overcoming the previous immune suppression and cost issues with allograft nerve transfers. New light is being shed regarding synthetic nerve conduits that combines various cytokines and growth factors. Stem cell studies applying biomolecular and biological engineering technologies also show good results. Despite this, further assessment are required for clinical application because these results are based primarily on animal studies.

Old Age, Female Sex, and Psychotropic Medications Predict Hyposalivation But Not Heart Rate Variability

Objective@#To explore risk factors for dry mouth and examine the clinical utility of the heart rate variability (HRV) test in the prediction of dry mouth. @*Methods@#Every outpatient, who underwent tests for both unstimulated salivary flow and HRV, was retrospectively reviewed. After excluding seven subjects, the demographics and clinical factors in 70 total patients were collected. Based on objective salivary flow rates, patients were classified into normal (≥0.2 mL/min) or hyposalivation groups (<0.2 mL/min), and inter-group comparisons were performed with a two-tailed statistical significance of 0.05. @*Results@#Patients with subjective dry mouth were significantly more likely to show hyposalivation. Advanced age, female sex, and current use of psychotropic medications were identified as risk factors for dry mouth. However, dry mouth was not associated with any HRV parameters. @*Conclusion@#HRV test did not demonstrate a clinical utility in predicting dry mouth. Because subjective dry mouth is significantly associated with objective hyposalivation, a simple probing question would be useful for early recognition of dry mouth. Clinical attention is required for patients meeting criteria of older age, female, and/or using psychotropic prescriptions. Prompt management of hyposalivation may improve quality of life and clinical outcome by enhanced treatment adherence.

A Nationwide Population-Based Study on the Association between Rosacea and Psychiatric Disorders: New Findings of Behavioral Disorders / 대한피부과학회지

Background@#Rosacea is a chronic skin inflammatory disorder that almost always occurs on the face, which can cause emotional stress and affect self-esteem. Rosacea is associated with psychiatric disorders, but there have been few studies on the relationship between rosacea and psychiatric disorders in Koreans. @*Objective@#We aimed to investigate the risk of psychiatric disorders in Korean patients with rosacea. @*Methods@#Data were obtained from the Korean National Health Insurance Service-National Sample Cohort. The database was collected according to the Korean Standard Classification of Diseases version 6, which is based on the International Classification of Diseases, 10th revision. This study was conducted with 595 patients diagnosed with rosacea from 2002 to 2013. A total of 2,380 controls were set by performing 1:4 matching for sex, age, and index year. @*Results@#The incidence of psychiatric disorders was higher in patients with rosacea (114/595, 19.16%) than in patients without rosacea (319/2,380, 13.40%), with a significant difference (p＜0.001). Among several types of psychiatric disorders, the prevalence of anxiety disorder and behavioral disorder was significantly higher in the rosacea patients than in patients without rosacea (p=0.008 and p=0.044, respectively). The adjusted hazard ratio for psychiatric disorders in patients with rosacea was 1.543 (95% confidence interval=1.238∼1.922, p＜0.001). @*Conclusion@#Rosacea is associated with many types of psychiatric disorders. Awareness of the psychological impact of rosacea might be helpful in improving patient quality of life.

Traumatic Posterior Chamber Intraocular Lens Dislocation into the Subconjunctival Space

Purpose@#Here we report a case of posterior chamber intraocular lens (IOL) dislocation into the subconjunctival space (pesudophacocele) following ocular trauma.Case summary: A 66-year-old male presented with ocular pain and decreased vision in the right eye following trauma with a metallic rod. The patient had a history of trabeculectomy, glaucoma drainage device implantation, transscleral cyclophotocoagulation, and cataract surgery for uveitic glaucoma and a cataract in the right eye. On examination, vision was hand movement, the intraocular pressure was 3 mmHg, and subconjunctival hemorrhage and hyphema were observed. After the resolution of hemorrhage, uveal tissue prolapse was seen nasally behind the corneal limbus and the IOL was found to be dislocated into the nasal subconjunctival space. There were no changes in the filtering bleb and tube compared to the pre-trauma status. The IOL was removed through a conjunctival incision because the patient refused any active treatment. @*Conclusions@#Pesudophacocele developed in a patient who had a history of glaucoma and cataract surgery in the injured eye. The IOL could not be assessed immediately after the trauma because of subconjunctival hemorrhage and hyphema. When the status of IOL is unclear or suspected to be dislocated after trauma, the possibility of pseudophacocele should be considered, in addition to the dislocation into the vitreous cavity.

Functional Connectivity Change Associated With Apolipoprotein E Allotypes Precedes Structural Connectivity and Neurodegeneration in Cognitive Normal Older Adults Without Cerebral Aβ Deposition

Objective@#Apolipoprotein E (APOE) gene is known to influence cerebral functional connectivity (FC) in Alzheimer’s disease continuum. We investigated association between APOE allotypes and FC, structural connectivity, and cortical thickness in amyloid-PET negative cognitive normal older adults (CN). @*Methods@#A total of 188 CN (37 had ε2/ε2 or ε2/ε3 [ε2 group], 113 had ε3/ε3 [ε3 group], and 38 had ε3/ε4 or ε4/ε4 [ε4 group]) were recruited. Voxel-based morphometry and cortical thickness analysis were used to investigate differences in cortical thickness between three APOE allotypes. To investigate integrity of structural connectivity, we analyzed diffusion weighted imaging using fractional anisotropy and mean diffusivity. In terms of FC, differences of FC in default mode network (DMN) among APOE allotypes were measured using functional magnetic resonance imaging. @*Results@#There were no significant differences in age, sex, education, cerebral beta-amyloid (Aβ) deposition severity, or neuropsychological profiles. No significant differences were found in cortical thickness and structural connectivity among the APOE allotypes. However, FC within the DMN was significantly lower in ε4 and ε2 carriers compared to ε3 homozygotes. @*Conclusion@#This study suggests that both ε4 and ε2 exhibit APOE-associated DMN FC changes before Aβ deposition, structural changes, and neurodegeneration.

Current evidence and the potential role of proton beam therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death, and external beam radiation therapy has emerged as a promising approach for managing HCC. Proton beam therapy (PBT) offers dosimetric advantages over X-ray therapy, with superior physical properties known as the Bragg peak. PBT holds promise for reducing hepatotoxicity and allowing safe dose-escalation to the tumor. It has been tried in various clinical conditions and has shown promising local tumor control and survival outcomes. A recent phase III trial demonstrated the non-inferiority of PBT in local tumor control compared to current standard radiofrequency ablation in early-stage HCC. PBT also tended to show more favorable outcomes compared to transarterial chemoembolization in the intermediate stage, and has proven effective in-field disease control and safe toxicity profiles in advanced HCC. In this review, we discuss the rationale, clinical studies, optimal indication, and future directions of PBT in HCC treatment.

Factors Associated with the Underuse of Sedatives and Neuromuscular Blocking Agents for Pediatric Emergency Endotracheal Intubation in Korea

Purpose@#Rapid sequence intubation (RSI) using sedatives and neuromuscular blocking agents (NMBAs) is recommended for pediatric emergency endotracheal intubation (ETI), but is not frequently performed in Korea. This study aimed to verify factors associated with the underuse of RSI medications. @*Materials and Methods@#This multicenter retrospective study reviewed patients aged under 18 years who underwent an ETI within 24 hours of arrival at the emergency department between 2016 and 2019. Any cases of ETI during cardiopulmonary resuscitation were excluded. We investigated the characteristics of the patients, intubators, RSI medications, and outcomes. The study cases were classified into no-medication, sedative-only, and sedative-with-NMBA groups. Multivariable logistic regression analysis of RSI medication use was conducted. @*Results@#A total of 334 cases with a median age of 3.4 years were included in this study. Sedatives and NMBAs were used in 63.8% and 32.9%, respectively. In comparing the no-medication (n=121), sedative-only (n=103), and sedative-with-NMBA (n=110) groups, patient age (median; 1.0 year vs. 2.8 years vs. 11.3 years; p<0.001), underlying medical conditions (77.7% vs. 56.3% vs. 36.4%; p<0.001), and pediatricians as intubators (76.9% vs. 54.4% vs. 17.3%; p<0.001) were different. The factors that influenced sedatives with NMBA use were patient age [for a year increment; adjusted odds ratio (aOR), 1.182; 95% confidence interval (CI), 1.120– 1.249], no underlying medical conditions (aOR, 2.109; 95% CI, 1.093–4.070), and intubators other than pediatricians (aOR, 5.123; 95% CI, 2.257–11.626). @*Conclusion@#RSI accounted for 32.9% of pediatric emergency ETI in Korea. The underuse of RSI medications is associated with younger patient age, underlying medical conditions, and pediatricians as intubators.

Benign Concentric Annular Macular Dystrophy in a Young Woman

Purpose@#Here, we report a case of benign concentric annular macular dystrophy associated with a visual field defect.Case summary: A 34-year-old woman presented with a visual field defect that was not accompanied by a deterioration in visual acuity. The patient’s best-corrected visual acuity was 1.25 in both eyes. No signs of anterior chamber inflammation were observed, and fundoscopy showed annular hypopigmentation at the fovea in both eyes. Annular hyperfluorescence was observed on fluorescein angiography due to the window defect. Automated perimetry demonstrated an annular paracentral scotoma in both eyes. The standard electroretinogram was normal, whereas optical coherence tomography showed a loss at the inner and outer boundaries of the foveal photoreceptors. The patient had no history of chloroquine or hydroxychloroquine intake, which excluded Bull’s eye maculopathy. The patient was observed without treatment for 2 years and no change was observed in her visual acuity or the appearance of the fovea. @*Conclusions@#Benign concentric annular macular dystrophy should be considered in patients with annular hypopigmentation at the fovea without deterioration in the visual acuity of both eyes.

Two Schwannomas Derived from the Ulnar Nerve Confirmed by Ultrasonography

Schwannoma is a rare tumor from the peripheral nerve and is mainly found alone. Diagnosis is made by ultrasonography or magnetic resonance imaging, and magnetic resonance imaging is preferred to ultrasonography for differential diagnosis of mass. After diagnosis, treatment is performed through surgical excision. In this case, a very small-sized neuropathy-causing lesion was identified through ultrasonography with electrodiagnostic study, and the other mass in the same nerve was discovered by chance through ultrasonography. Both masses were identified as schwannoma originating from the ulnar nerve and were successfully excised. We confirmed the advantages of ultrasonography in the rare diagnosis and again showed that ultrasonography has a diagnostic value that is not inferior to magnetic resonance imaging. Also, cases of multiple schwannomas confined to the ulnar nerve are rare and have been rarely reported worldwide. Therefore, it is reported together with the previous reports.

Effect of fever or respiratory symptoms on leaving without being seen during the COVID-19 pandemic in South Korea

Objective@#Coronavirus disease 2019 (COVID-19) has notably altered the emergency department isolation protocol, imposing stricter requirements on probable infectious disease patients that enter the department. This has caused adverse effects, such as an increased rate of leave without being seen (LWBS). This study describes the effect of fever/respiratory symptoms as the main cause of isolation regarding LWBS after the COVID-19 pandemic. @*Methods@#We retrospectively analyzed emergency department visits before (March to July 2019) and after (March to July 2020) the COVID-19 pandemic. Patients were grouped based on existing fever or respiratory symptoms, with the LWBS rate as the primary outcome. Logistic regression analysis was used to identify the risk factors of LWBS. Logistic regression was performed using interaction terminology (fever/respiratory symptom patient [FRP] × post–COVID-19) to determine the interaction between patients with FRPs and the COVID-19 pandemic period. @*Results@#A total of 60,290 patients were included (34,492 in the pre–COVID-19, and 25,298 in the post–COVID-19 group). The proportion of FRPs decreased significantly after the pandemic (P < 0.001), while the LWBS rate in FRPs significantly increased from 2.8% to 19.2% (P < 0.001). Both FRPs (odds ratio, 1.76; 95% confidence interval, 1.59–1.84 (P < 0.001) and the COVID-19 period (odds ratio, 2.29; 95% confidence interval, 2.15–2.44; P < 0.001) were significantly associated with increased LWBS. Additionally, there was a significant interaction between the incidence of LWBS in FRPs and the COVID-19 pandemic period (P < 0.001). @*Conclusion@#The LWBS rate has increased in FRPs after the COVID-19 pandemic; additionally, the effect observed was disproportionate compared with that of nonfever/respiratory symptom patients.

Phentermine and Phendimetrazine-Induced Psychotic Disorder and Bipolar Disorder: A Case Series

Objectives@#Recently, weight loss has emerged as a national concern in South Korea, and this has resulted in an increase in the frequency of use of central nervous system (CNS)-stimulating appetite suppressants. This study aimed to collect cases of psychotic disorders and bipolar disorders triggered by phentermine and phendimetrazine and explore the clinical features and courses. @*Methods@#In this retrospective study, we analyzed the electronic medical records of patients and selected eight patients who developed psychotic symptoms and manic symptoms for the first time after taking phentermine and phendimetrazine. All cases were reviewed, and their clinical features and course were summarized. @*Results@#All eight patients developed psychotic symptoms, and one had accompanying manic symptoms. The final diagnosis was appetite-suppressant-induced psychotic disorder in four patients, schizophrenia in three, and appetite-suppressant-induced bipolar disorder in one. In addition, three patients were diagnosed as having substance-use disorder. The key psychotic symptoms of these patients were hallucinations and paranoia. @*Conclusions@#These case findings suggest that phentermine and phendimetrazine can cause psychotic disorder, bipolar disorder, or substance use disorder and that medical professionals and the public should practice caution when prescribing and using these drugs.

Reference Standards for Nerve Conduction Studies of Individual Nerves of Lower Extremity With Expanded Uncertainty in Healthy Korean Adults

Objective@#To develop a set of reference standards for tibial motor, common peroneal motor, sural sensory, and superficial peroneal sensory nerve conduction studies (NCSs) with expanded uncertainty in a healthy Korean population. @*Methods@#Standardized procedures were conducted for individual lower extremity NCSs of 199 healthy participants in their 20s (n=100) and 50s (n=99). Mean values and expanded uncertainties for parameters were analyzed with thorough consideration of multiple uncertainty factors under the International Guide to the Expression of Uncertainty in Measurement. In addition, side-to-side differences in onset latency, amplitude, and nerve conduction velocity (NCV) were analyzed. @*Results@#Mean (reference range) for distal onset latency, baseline to negative peak amplitude, NCV of tibial motor nerve in males in their 20s were 4.3 ms (3.1–5.4 ms), 7.1 mV (3.4–10.9 mV), and 50.7 m/s (42.2–59.3 m/s), respectively; sural sensory nerve baseline to negative peak amplitude in males in their 20s was 21.7 μV (8.3–35.2 μV). Including the aforementioned data, we present a vast dataset of normative mean values and expanded uncertainties for NCSs of the leg in a healthy Korean population. Furthermore, upper limits for normal side-to-side differences for onset latency, amplitude, and NCV of each nerve are suggested. @*Conclusion@#To our knowledge, this is the first study to present the reference standards of leg NCSs with consideration for multifactorial uncertainties in an Asian population. We expect these results to help practitioners make reliable and reproducible clinical decisions.

Hospital-Based Case Management for Suicide High-Risk Group Using Delphi Survey

Objective@#As of 2019, suicide is serious problem in Korea, with the highest suicide rate among OECD countries. To reduce suicide rates Emergency Department Based Post-Suicide Attempt Case Management carried out with government funding in South Korea, but it is insufficient to address the issue. Aim of this study is to prevent suicide attempts through continuous provision of mental health services even after discharge from acute care. @*Methods@#We selected 15 mental health specialists who are multidisciplinary experts in Suicide Prevention. Two-round Delphi survey was conducted on them to reach an agreement for hospital-based case management. @*Results@#The first Delphi survey consisted of 8 areas and 39 questions. Among them, 30 questions draw agreement above the reference value. The second Delphi survey, consisted of 37 questions, resulted in 32 above-standard questions. @*Conclusion@#Consensus was reached in most category of the Hospital Based Case Management for Suicide High-Risk Group. Core of the developed plan was to provide services to patients who visited the hospital, pursue the stability and universalization of services through a medical insurance fee system. In the future, hospital-based case management service will be implemented as a new model contributing to the reduction of suicide rates in Korea.

Factors Associated With Dementia Knowledge and Dementia Worry in the South Korean Elderly Population

Objective@#South Korea is one of the countries with a very fast aging rate, and the prevalence of dementia is rapidly increasing. However, there are relatively few studies pertaining to sociodemographic and physical health-related factors associated with dementia knowledge and dementia worry. @*Methods@#This was a cross-sectional survey of a community in Seocho-gu, Seoul, Republic of Korea. Overall, 1,869 adults aged 60 years participated. Participants completed an online interview or face-to-face interview. Survey data comprised self-report questions including dementia knowledge, dementia worry, demographic, psychological, exercise, and cognitive activities. We conducted logistic regression analysis. @*Results@#There was a significant positive association between dementia worry and knowledge. Family history of dementia, education, income, sleep problems, depressed mood and loss of volition, chronic diseases, and presence of a past job were associated with dementia knowledge or worry. Reading, art, or social cognitive activities had a significant positive association with dementia knowledge, and writing or musical cognitive activities had a negative association with dementia worry. @*Conclusion@#We found that people with more dementia knowledge and less dementia worry engaged more in cognitive activities that could prevent dementia. Public education should be planned to improve dementia knowledge and reduce dementia worry.

Epidemiologic features of pediatric genital injury in emergency departments in Korea

Purpose@#Genital injury is a common pediatric injury. Given the lack of nationwide data, the authors aimed to show age group-related epidemiologic features of genital injury in Korea. @*Methods@#We reviewed the data from 2011-2016 Emergency Department-based Injury In-depth Surveillance registry, which involves 23 emergency departments in Korea. From the dataset, we included children (< 18 years) with the International Classification of Diseases, 10th Revision codes related to genital injury as the final diagnosis with excluding those with other codes or combined injuries. Age groups were defined as follows; infants (< 1 year), toddlers (1-3), preschoolers (4-6), schoolers (7-12), and adolescents (13-17). The clinical features and outcomes were analyzed. @*Results@#A total of 3,030 children were included with the median age of 6 years (interquartile range, 4-10) and the proportion of girls of 53.0%. Only 144 children (4.8%) were transported by the emergency medical service providers. The most common mechanism and place were blunt injury (1,826 [60.3%]) and home (1,535 [50.7%]), respectively. Of the codes, “Contusion of external genital organs (S30.2)” was most common (1,574 [51.9%]). As for outcomes, 2,770 children (91.4%) were discharged, 252 (8.3%) were hospitalized (intensive care units, 1 child [0.03%]), and 108 (3.6%) underwent surgery. Severe injury occurred in 111 children (3.7%) without a mortality. With increasing age in the age groups, non-accidental injury, school and sports-related injuries, hospitalization, and surgery (All Ps < 0.001). @*Conclusion@#Genital injury may occur at evening, in spring and summer, at home, and in the form of accidental or blunt injury. Most children are discharged. Contrary to these general features, older children tend to undergo more frequently non-accidental injury, school and sports-related injuries, hospitalization, and surgery. Thus, we need age-specific strategies for injury prevention.

How COVID-19 Affected Healthcare Workers in the Hospital Locked Down due to Early COVID-19 Cases in Korea

Background@#The healthcare workers (HCWs) were exposed to never-experienced psychological distress during the early stage of the coronavirus disease 2019 (COVID-19) pandemic. The aim of this study was to investigate how the COVID-19 pandemic affected the mental health of HCWs during the hospital lockdown period due to mass healthcare-associated infection during the early spread of COVID-19. @*Methods@#A real-time online survey was conducted between April 14–18, 2020 among HCWs who worked at the university hospital where COVID-19 was confirmed in a patient, and the hospital was shut down for 3 weeks. Along with demographic variables and work-related information, psychological distress was measured using the Generalized Anxiety Disorder-7 (GAD-7), the Patient Health Questionnaire-9 (PHQ-9), the Maslach Burnout Inventory-General Survey scale, and the Stress and Anxiety to Viral Epidemics-9. @*Results@#The HCWs working in the cohort ward and those who have experienced social discrimination had significantly higher level of depression (PHQ-9 score; 5.24 ± 4.48 vs. 4.15 ± 4.38; P < 0.01 and 5.89 ± 4.78 vs. 3.25 ± 3.77; P < 0.001, respectively) and anxiety (GAD-7 score; 3.69 ± 3.68 vs. 2.87 ± 3.73;P < 0.05 and 4.20 ± 4.22 vs. 2.17 ± 3.06; P < 0.001, respectively) compared to other HCWs. Worries regarding the peer relationship and the skepticism about job were associated with depression (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.07–1.79; P < 0.05 and OR, 1.69; 95% CI, 1.31–2.17; P < 0.001, respectively) and anxiety (OR, 1.73; 95% CI, 1.21–2.49; P < 0.01 and OR, 1.54; 95% CI, 1.09–2.17; P < 0.05, respectively), while fear of infection or worsening of health was not. Path analysis showed that work-related stress associated with the viral epidemic rather than anxiety about the viral epidemic mainly contributed to depression. @*Conclusion@#The present observational study indicates that mental health problems of HCWs exposed to COVID-19 are associated with distress in work and social relationship. Early intervention programs focusing on these factors are necessary.

Association of Sub-Threshold Amyloid Retention With Neuropsychological Performance in Cognitively Normal Older Adults Without the APOE ε4 Allele

Objective@#Recent evidence shows that the quantitative value of amyloid-beta (Aβ) deposition below the threshold of Aβ positivi-ty carries biological and clinical significance regarding future cognitive decline. We evaluated whether the quantitative value of sub-threshold Aβ deposition had a significant correlation with neuropsychological test scores in cognitively normal older adults without the APOE ε4 allele. @*Methods@#Sixty cognitively normal APOE ε4 allele non-carriers with negative Aβ retention aged 60 to 85 years were included in this study. We assessed neuropsychological performance with the Korean version of the Consortium to Establish a Registry for Al-zheimer’s Disease (CERAD-K) and obtained standardized [ 18 F] flutemetamol uptake values in the pons as a reference (SUVR PONS), evaluated with PET. Multiple regression analyses were conducted to assess the effect of global and regional Aβ load on cognitive performance, adjusting for age, sex, years of education, and volumes of white matter hyperintensities. @*Results@#We found that Aβ deposition in the precuneus, posterior cingulate cortex, and parietal lobe had a significant association with the total CERAD-K scores. There was also a significant correlation between the SUVR PONS in the precuneus and the CERAD-K total score after Bonferroni correction. @*Conclusion@#Subthreshold Aβ retention in the core brain regions of the default mode network could affect cognitive functions in the cognitively normal APOE ε4 non-carriers, considered to be the lowest risk group for Alzheimer’s disease (AD).

Patterns of Proton Beam Therapy Use in Clinical Practice between 2007 and 2019 in Korea / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Proton beam therapy (PBT) is a state-of-the-art technology employed in radiotherapy (RT) for cancer patients. This study characterized how PBT has been used in clinical practice in Korea. @*Materials and Methods@#Patients who received any type of RT between 2007 and 2019 were identified from the radiation oncology registry of the two PBT facilities operating in Korea (National Cancer Center and Samsung Medical Center). The chi-square test was used to identify patient- and treatment-related characteristics associated with the receipt of PBT. @*Results@#A total of 54,035 patients had been treated with some form of RT in the two institutions, of whom 5,398 received PBT (10.0%). The number of patients who receive PBT has gradually increased since PBT first started, from 162 patients in 2007 to 1,304 patients in 2019. Among all types of cancer, PBT use in liver cancer has been steadily increasing from 20% in 2008-2009 to 32% in 2018-2019. In contrast, that in prostate cancer has been continuously decreasing from 20% in 2008-2009 to < 10% in 2018-2019. Male sex, very young or old age, stage I-II disease, residency in non-capital areas, a definitive setting, a curative treatment aim, enrollment in a clinical trial, re-irradiation and insurance coverage were significantly associated with the receipt of PBT (all p < 0.05). @*Conclusion@#Since PBT started in Korea, the number of patients receiving PBT has increased to more than 1,000 per year and treatment indications have expanded. Liver cancer is the most common primary tumor among all PBT cases in Korea.

Peripheral Nerve Regeneration Using a Nerve Conduit with Olfactory Ensheathing Cells in a Rat Model

BACKGROUND@#Autologous nerve grafts are the gold standard treatment for peripheral nerve injury treatment. However, this procedure cannot avoid sacrificing other nerves as a major limitation. The aim of the present study was to evaluate the potential of olfactory ensheathing cells (OECs) embedded in a nerve conduit. @*METHODS@#A 10-mm segment of the sciatic nerve was resected in 21 rats, and the nerve injury was repaired with one of the following (n = 7 per group): autologous nerve graft, poly (ε-caprolactone) (PCL) conduit and OECs, and PCL conduit only. The consequent effect on nerve regeneration was measured based on the nerve conduction velocity (NCV), amplitude of the compound muscle action potential (ACMAP), wet muscle weight, histomorphometric analysis, and nerve density quantification. @*RESULTS@#Histomorphometric analysis revealed nerve regeneration and angiogenesis in all groups. However, there were significant differences (p  0.05). No significant results in NCV, wet muscle weight, and nerve density quantification were observed among the 3 groups. @*CONCLUSION@#A PCL conduit with OECs enhances the regeneration of injured peripheral nerves, offering a good alternative to autologous nerve grafts.

Upregulation of receptor tyrosine kinase-like orphan receptor 2 in idiopathic pulmonary fibrosis

Background/Aims@#Receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a major regulator of Wnt signaling, which is involved in fibroblast dysfunction. Because its role has not been evaluated in idiopathic pulmonary fibrosis (IPF), we examined the clinical implications of ROR2 expression. @*Methods@#ROR2 mRNA expression was measured using reverse transcription polymerase chain reaction in lung tissue-derived fibroblasts from IPF patients (n = 14) and from controls (n = 10). ROR2 protein was measured using enzyme-linked immunosorbent assay in primary fibroblasts from IPF patients (n = 14) and controls (n = 10), and in bronchoalveolar lavage (BAL) fluids obtained from normal controls (NC; n = 30). IPF patients (n = 84), and other patients with interstitial lung diseases, including nonspecific interstitial pneumonia (NSIP; n = 10), hypersensitivity pneumonitis (HP; n = 10), and sarcoidosis (n = 10). @*Results@#ROR2 mRNA and protein levels were significantly higher in IPF fibroblasts than in controls (p = 0.003, p = 0.0017, respectively). ROR2 protein levels in BAL fluids from patients with IPF were significantly higher than in those from NC (p < 0.001), and from patients with NSIP (p = 0.006), HP (p = 0.004), or sarcoidosis (p = 0.004). Receiver operating characteristic curves showed a clear difference between IPF and NC in ROR2 protein level (area under the curve, 0.890; confidence interval, 0.829 to 0.950; p < 0.001). ROR2 protein levels were significantly higher in GAP stage III than in GAP stages I and II (p = 0.016). @*Conclusions@#ROR2 may be related to the development of IPF, and its protein level may be a useful and severity-dependent candidate marker for IPF.