Generation and analysis of whole-genome sequencing data in human mammary epithelial cells

Breast cancer is the most common cancer worldwide, and advanced breast cancer with metastases is incurable mainly with currently available therapies. Therefore, it is essential to understand molecular characteristics during the progression of breast carcinogenesis. Here, we report a dataset of whole genomes from the human mammary epithelial cell system derived from a reduction mammoplasty specimen. This system comprises pre-stasis 184D cells, considered normal, and seven cell lines along cancer progression series that are immortalized or additionally acquired anchorage-independent growth. Our analysis of the whole-genome sequencing (WGS) data indicates that those seven cancer progression series cells have somatic mutations whose number ranges from 8,393 to 39,564 (with an average of 30,591) compared to 184D cells. These WGS data and our mutation analysis will provide helpful information to identify driver mutations and elucidate molecular mechanisms for breast carcinogenesis

Evaluation of the efficacy and safety of conversion from the tacrolimus capsule to tablet in stable liver transplant recipients with maintenance therapy: a 24-week, open-label, single-center, phase IV exploratory clinical study

Purpose@#The tablet form of tacrolimus is more convenient for drug ingestion than the capsule form. We examined the efficacy and safety of tacrolimus tablets and a satisfaction survey after formula conversion in liver transplant (LT) recipients. @*Methods@#This study was an open-label, prospective clinical trial for tacrolimus formula 1:1 conversion from capsule to tablet in 41 adult LT recipients with tacrolimus maintenance therapy of more than 1 month. The primary endpoint was incidence of biopsy-proven acute rejection (BPAR) within 24 weeks. Surveys 1 week before and 4 weeks after formula conversion were conducted for total daily dose of medication, number, scale of discomfort and satisfaction. @*Results@#The overall incidence of BPAR was 0% and there was no graft loss or patient death. The incidence of adverse effects was 34.1% (n = 14) after formula conversion. The most common severe adverse effect was abnormal liver function test (n = 5): biliary complications (n = 4) and alcoholic recidivism (n = 1). Total daily dose and number of tacrolimus doses were significantly lower after formula conversion (P < 0.05) without changes in trough level. According to survey analysis, there was no significant difference in discomfort and satisfaction scales from capsule to tablet conversion (P < 0.05). @*Conclusion@#The present study suggests that the new tablet formula can be a useful treatment option to maintain a consistent level of tacrolimus with a lower total daily dose and number in adult LT recipients.

Recurrence in patients with totally necrotic nodules of hepatocellular carcinoma after liver transplantation: “totally” an inaccurate description

Purpose@#Total necrosis of hepatocellular carcinoma (HCC) achieved via locoregional treatment (LRT) is considered to indicate a lack of tumor viability. Nonetheless, there is insufficient evidence of recurrence after liver transplantation (LT) in patients with such a status. The aim of this study was to investigate the prognosis of patients diagnosed with totally necrotic nodules upon explant hepatectomy after LT. @*Methods@#We conducted a retrospective study of patients diagnosed with totally necrotic nodules after LT for HCC. A total of 165 patients with HCC who underwent living- or deceased-donor LT from 2000 to 2020 in our hospital were included. @*Results@#A total of 5 patients (3.0%) exhibited HCC recurrence during a median follow-up of 84 months (range, 4–243 months) after LT. The 5-year overall and recurrence-free survival rates of these patients were 92.8% and 92.2%, respectively. Four patients in the HCC-recurrence group (80.0%) died even after further treatment, including transarterial chemoembolization, surgery, and systemic treatment. Both univariate and multivariate analyses of clinicopathological factors identified a maximum diameter of the totally necrotic nodules of >5 cm as the only factor associated with tumor recurrence following LT (P = 0.005 and P = 0.009, respectively). @*Conclusion@#Total necrosis of HCC via LRT yielded excellent survival outcomes for patients undergoing LT. Nevertheless, patients with large tumors should be considered at high risk of recurrence after LT, suggesting the need for their active surveillance during the follow-up period.

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.

Efficacy of Extracorporeal Shock Wave Therapy in Neck and Shoulder Pain Syndrome / 대한스포츠의학회지

Purpose@#The aim of current study is to verify the efficacy of extracorporeal shock wave therapy (ESWT) in neck and shoulder pain syndrome. @*Methods@#We enrolled 23 patients with neck and shoulder pain syndrome (mean age, 55±16 years; onset, 12.65±8.90 months) who underwent ESWT from July to December 2019. ESWT (4 to 5 bar or 0.23–0.45 mJ/mm 2 , 1,500 to 2,000 times/region, 7 Hz) was performed at least 4 consecutive times per week. Evaluated outcomes were visual analogue scale (VAS) of pain and tenderness, neck disability index (NDI), and shoulder passive range of motion (ROM; forward flexion [FF], external rotation at neutral [ER], internal rotation at back [IR]). Pain and tenderness VAS scores were assessed at every follow-up, while NDI and shoulder ROM were evaluated two times before treatment and at the final follw-up (at 4.52±0.73 weeks). @*Results@#The pain VAS score decreased from 5.5±2.4 at first visit to 4.0±1.8 (p=0.001), 3.3±2.1 (p=0.02), and 3.1±2.2 (p=0.29) at the first, second, and third follow-up visits. The tenderness VAS at first visit was 5.98±1.89, which decreased to 5.17±1.83 (p=0.005), 4.61±1.67 (p=0.05), and 4.09±1.92 (p=0.06) at the first, second, and third follow-up visits. NDI was significantly reduced from 18.04±8.86 to 10.04±6.94 at last follow-up (p=0.001) and shoulder ROM was significantly improved after treatment (FF: 159.6°±28.0° to 177.8°±8.5°, p=0.001; ER: 72.2±15.7° to 79.6±2.1°, p=0.02; IR: 10.2±3.49 [T 10] to 6.9±1.7 [T 7], p=0.001). @*Conclusion@#Consecutive ESWT was effective in treating neck and shoulder pain syndrome with functional improvement and pain reductio

Bioinformatics services for analyzing massive genomic datasets

The explosive growth of next-generation sequencing data has resulted in ultra-large-scale datasets and ensuing computational problems. In Korea, the amount of genomic data has been increasing rapidly in the recent years. Leveraging these big data requires researchers to use large-scale computational resources and analysis pipelines. A promising solution for addressing this computational challenge is cloud computing, where CPUs, memory, storage, and programs are accessible in the form of virtual machines. Here, we present a cloud computing-based system, Bio-Express, that provides user-friendly, cost-effective analysis of massive genomic datasets. Bio-Express is loaded with predefined multi-omics data analysis pipelines, which are divided into genome, transcriptome, epigenome, and metagenome pipelines. Users can employ predefined pipelines or create a new pipeline for analyzing their own omics data. We also developed several web-based services for facilitating downstream analysis of genome data. Bio-Express web service is freely available at https://www.bioexpress.re.kr/.

Bioinformatics services for analyzing massive genomic datasets

The explosive growth of next-generation sequencing data has resulted in ultra-large-scale datasets and ensuing computational problems. In Korea, the amount of genomic data has been increasing rapidly in the recent years. Leveraging these big data requires researchers to use large-scale computational resources and analysis pipelines. A promising solution for addressing this computational challenge is cloud computing, where CPUs, memory, storage, and programs are accessible in the form of virtual machines. Here, we present a cloud computing-based system, Bio-Express, that provides user-friendly, cost-effective analysis of massive genomic datasets. Bio-Express is loaded with predefined multi-omics data analysis pipelines, which are divided into genome, transcriptome, epigenome, and metagenome pipelines. Users can employ predefined pipelines or create a new pipeline for analyzing their own omics data. We also developed several web-based services for facilitating downstream analysis of genome data. Bio-Express web service is freely available at https://www.bioexpress.re.kr/.

Evaluation of the prevalence of musculoskeletal symptoms, presumptive diagnosis, medical care use, and sick leave among female school meal service workers

BACKGROUND: Most of the school meal service workers in Korea are middle-aged individuals. They have high workload, which increases their incidence of musculoskeletal disorders. This study aimed to evaluate the prevalence and risk factors of subjective musculoskeletal symptoms, presumptive diagnosis, medical care use, and sick leave among female school meal workers. METHODS: We analyzed the results of musculoskeletal disease screening of 1581 female school meal workers. The screening consisted of self-administered questionnaire, history taking by occupational physicians, and physical examination. The prevalence of subjective musculoskeletal symptoms, presumptive diagnosis after initial examination by occupational physicians, use of medical care for more than 7 days, and sick leave due to musculoskeletal diseases during the past year were evaluated in this study. The relative risk of four outcome indicators of musculoskeletal disorders was compared with respect to potential factors, such as age, subjective physical loading, present illness, injury experience, and type of school, using log-binomial regression. RESULTS: The prevalence of subjective musculoskeletal symptom was 79.6%; presumptive diagnosis, 47.6%; hospital visits over 7 days, 36.4%; and sick leave, 7.3%. The relative risk of musculoskeletal symptoms by age (≥50 years vs < 50 years) was 1.04 (95% confidence interval (CI): 1.00–1.09); presumptive diagnosis of musculoskeletal disease, 1.17 (95% CI: 1.06–1.30); hospital visits over 7 days, 1.26 (95% CI: 0.85–1.85); and sick leave, 1.17 (95% CI: 1.02–1.34). The relative risk of musculoskeletal symptoms due to subjective physical loading (very hard vs low) was 1.45 (95% CI: 1.33–1.58); presumptive diagnosis, 2.92 (95% CI: 2.25); hospital visits over 7 days, 1.91 (95% CI: 1.02–3.59); and sick leave, 2.11 (95% CI: 1.63–2.74). CONCLUSIONS: Subjective physical loading was a more important factor in musculoskeletal disorders than the age of female school meal workers.

Computed Tomography Arthrography Findings of Idiopathic Adhesive Capsulitis of the Hip: An Analog of Adhesive Capsulitis of the Shoulder

OBJECTIVE: To identify useful imaging findings for the diagnosis of idiopathic adhesive capsulitis of the hip (ACH) on computed tomography arthrography (CTA). MATERIALS AND METHODS: Twenty-eight consecutive patients (29 hips; 7 males; mean age, 45.7 years; age range, 17–67 years) with ACH from October 2009 to March 2017 and 29 age- and sex-matched control patients from 2014 to 2016 were enrolled. All CTA images were evaluated by 2 radiologists independently for joint distensibility (anterior-posterior [AP] and superior-inferior [SI] joint cavity filling ratios), the presence of contrast filling around the ligamentum teres, and extracapsular contrast leakage. Fisher's exact test, Mann-Whitney U test, analysis of variance, and receiver operating characteristic curves were used for statistical analysis. P value less than 0.05 was considered to indicate statistical significance. RESULTS: The anterior joint cavity was significantly more obliterated in the ACH group (mean size, 3.7–4.0 mm) than in the control group (mean size, 4.8–5.0 mm; p < 0.05). The AP filling ratio was also significantly lower in the ACH group (0.6 vs. 1.1; p < 0.05) and decreased more as the ACH stage increased (mean anterior joint cavity size: 1.15 mm in stage 3 vs. 4.68 mm in stage 1; p < 0.05). Extracapsular contrast leakage was more common in the ACH group (27–28 vs. 20–21; p = 0.041 and 0.025, respectively). CONCLUSION: On CTA, the anterior joint cavity may have earlier and more marked obliteration than joint cavities on other sides, and may be accompanied by extracapsular contrast leakage in ACH. These CTA findings may be helpful in the diagnosis of ACH.

Epidural Abscess Caused by Eikenella corrodens in a Previously Healthy Child

Eikenella corrodens rarely causes invasive head and neck infections in immunocompetent children. We report a case of epidural abscess caused by E. corrodens in a previously healthy 13-year-old boy who presented with fever, headache, and vomiting. On physical examination upon admission, there was no neck stiffness, but discharge from the right ear was observed. Brain magnetic resonance imaging (MRI) revealed approximately 4.5-cm-sized epidural empyema on the right temporal lobe as well as bilateral ethmoid and sphenoid sinusitis, right mastoiditis, and right otitis media. During treatment with vancomycin and cefotaxime, purulent ear discharge aggravated, and on follow-up brain MRI, the empyema size increased to 5.6×3.4 cm with interval development of an abscess at the right sphenoid sinus. Burr hole trephination was performed, and foul-smelling pus was aspirated from the epidural abscess near the right temporal lobe. Pus culture yielded E. corrodens. Endoscopic sphenoidotomy was also performed with massive pus drainage, and the same organism was grown. The patient was treated with intravenous cefotaxime for 3 weeks and recovered well with no other complications. Therefore, E. corrodens can cause serious complications in children with untreated sinusitis.

Comparison of Outcomes between Direct-to-Implant Breast Reconstruction Following Nipple-Sparing Mastectomy through Inframammary Fold Incision versus Noninframammary Fold Incision / 한국유방암학회지

PURPOSE: In properly selected patients with breast cancer, nipple-sparing mastectomy (NSM) is generally considered safe by oncologic standards. We examined two groups of patients who underwent direct-to-implant (DTI) reconstruction after NSM, comparing complications encountered, revision rates, and aesthetic outcomes. The patients were stratified based on type of surgical incision and assigned to inframammary fold (IMF) and non-IMF groups. METHODS: We investigated 141 patients (145 breasts) subjected to NSM and immediate DTI reconstruction between 2013 and 2016. A total of 62 breasts (in 58 patients) were surgically removed via IMF incisions, with the other 83 breasts (in 83 patients) removed by non-IMF means. RESULTS: Complications associated with IMF (n=62) and non-IMF (n=83) incisions were as follows: skin necrosis (IMF, 9; non-IMF, 18); hematoma (IMF, 3; non-IMF, 4); seroma (IMF, 8; non-IMF, 4); mild capsular contracture (IMF, 4; non-IMF, 7); and tumor recurrence (IMF, 2; non-IMF, 8). Surgical revisions were counted as duplicates (IMF, 18; non-IMF, 38). Aesthetic outcomes following IMF incisions were rated as very good (44.2%), good (23.1%), fair (23.1%), or poor (9.6%). CONCLUSION: IMF incision enables complete preservation of the nipple-areolar complex, yielding superior aesthetic results in immediate DTI breast reconstruction after NSM. The nature of incision used had no significant impact on postoperative complications or reoperation rates and had comparable oncologic safety to that of non-IMF incisions. IMF incisions produced the least visible scarring and did not affect breast shape. Most patients were satisfied with the aesthetic outcomes.

Forehead reconstruction with a custom-made three-dimensional titanium implant in a Parry-Romberg syndrome patient

Parry-Romberg syndrome is a rare neurocutaneous syndrome characterized by progressive shrinkage and degeneration of the tissues usually on only one side of the face. It is usually difficult to restore the facial contour due to skin tightness. In this case report, we report a forehead reconstruction with custom-made three-dimensional (3D) titanium implant of a Parry-Romberg syndrome patient who was treated with multiple fat grafts but had limited effect. A 36-year-old man presented with hemifacial atrophy. The disease progressed from 5 to 16 years old. The patient had alopecia on frontal scalp and received a surgery using tissue expander. The alopecia lesion was covered by expanded scalp flap done 22 years ago. Also, he was treated with fat grafts on depressed forehead 17 years ago. However, it did not work sufficiently, and there was noted depressed forehead. We planned to make 3D titanium implant to cover the depressed area (from the superior orbital rim to the vertex). During the operation, we confirmed that the custom-made 3D implant accurately fit for the depressed area without any dead spaces. Previously depressed forehead and glabella were elevated, and the forehead contour was improved cosmetically. A custom-made 3D titanium implant is widely used for skull reconstruction and bring good results. In our case, the depressed forehead of a Parry-Romberg syndrome patient was improved by a 3D titanium implant.

The Radiologic Comparison of Operative Treatment Using a Hook Plate versus a Distal Clavicle Locking Plate of Distal Clavicle Fracture

BACKGROUND: The purpose of this study was to compare the radiologic results of patients who underwent surgery with a hook plate and a locking plate in distal clavicle fractures. METHODS: Sixty patients underwent surgical treatment for Neer type IIa, IIb, III, and V distal clavicle fracture. Twenty-eight patients underwent fracture fixation with a hook plate and 32 with a locking plate. Coracoclavicular distance was measured on standard anteroposterior radiographs before and after the surgery, and union was confirmed by radiograph or computed tomography taken at 6 months postoperatively. Other radiologic complications like osteolysis was also checked. RESULTS: Bony union was confirmed in 59 patients out of 60 patients, and 1 patient in the hook plate group showed delayed union. Coracoclavicular distance was decreased more in the hook plate group after surgery (p < 0.01). After 6 weeks of the hook plate removal, the coracoclavicular distance was increased a little compared to before metal removal, but there was no difference compared to the contralateral shoulder. Eleven out of 28 patients (39.3%) showed osteolysis on the acromial undersurface in the hook plate group. CONCLUSIONS: Both the hook plate group and the locking plate group showed satisfactory radiologic results in distal clavicle fractures. Both hook plate and locking plate could be a good treatment option if it is used in proper indication in distal clavicle fracture with acromioclavicular subluxation or dislocation.

Clinical and Radiological Results of Hook Plate Fixation in Acute Acromioclavicular Joint Dislocations and Distal Clavicle Fractures

BACKGROUND: The purpose of this study was to evaluate the clinical outcomes and complications of hook plate fixation in acromioclavicular (AC) joint dislocations and distal clavicle fractures. METHODS: We retrospectively reviewed a series of 60 consecutive patients with hook plate fixation for AC joint dislocation (group I) and distal clavicle fracture (group II). Groups I and II had 39 and 21 patients, respectively. Clinical results were evaluated using the pain visual analogue scale (VAS), simple shoulder test, and Constant-Murley scores. In addition, subacromial erosion and stiffness were evaluated as complications. RESULTS: At the removal, the pain VAS was 2.69 ± 1.30 and 4.10 ± 2.14 in groups I and II, respectively, which were significantly different (p=0.003). The simple shoulder test score was 9.59 ± 1.60 and 7.81 ± 2.67 in groups I and II, respectively, which were also significantly different (p=0.002). Subacromial erosion was significantly more frequent in group II (14/21 patients, 66.7%) than in group I (15/39 patients, 38.5%) (p=0.037), and stiffness was also higher in group II (17/21 patients, 81.0%) than in group I (22/39 patients, 56.4%), but it was not significant. CONCLUSIONS: Hook plate fixation showed good clinical and functional results for the treatment of acute unstable AC joint dislocation and distal clavicle fracture. But, in distal clavicle fractures, there are more subacromial erosion and stiffness compare with acute unstable AC joint dislocation.

Magnoliae Cortex and maize modulate Porphyromonas gingivalis-induced inflammatory reactions

PURPOSE: The aim of this study was to evaluate the capacity of single and combined applications of the bark of the stems and roots of Magnolia officinalis Rehd. et Wils. (Magnoliae Cortex) and Zea mays L. (maize) to modulate inflammation in RAW 264.7 cells stimulated with Porphyromonas gingivalis. METHODS: RAW 264.7 cells were stimulated with P. gingivalis, and Magnoliae Cortex and/or maize was added. Cytotoxicity and the capacity to modulate inflammation were determined with a methylthiazol tetrazolium (MTT) assay, nitrite production, enzyme-linked immunosorbent assay (ELISA), and western blotting. RESULTS: Treatment with Magnoliae Cortex and/or maize inhibited nuclear transcription factor κB (NF-κB) pathway activation and nuclear p44/42 mitogen-activated protein kinase (MAPK) and inducible nitric oxide synthase (iNOS) protein expression in P. gingivalis-stimulated RAW 264.7 cells. Moreover, the treatments suppressed cytokines (prostaglandin E2 [PGE2], interleukin [IL]-1β, and IL-6) and nitrite production. CONCLUSIONS: Both Magnoliae Cortex and maize exerted an anti-inflammatory effect on P. gingivalis-stimulated RAW 264.7 cells, and this effect was more pronounced when the extracts were combined. These findings show that these extracts may be beneficial for slowing the progression of periodontal disease.

Initial Experience of Transperineal Biopsy After Multiparametric Magnetic Resonance Imaging in Korea; Comparison With Transrectal Biopsy

PURPOSE: The aim of this study is to confirm the detection rate of transperineal biopsy after multiparametric magnetic resonance imaging (mpMRI) and compared it to that of transrectal biopsy. We also examined the role of mpMRI and the rate of complications for each method. MATERIALS AND METHODS: In a retrospective study, we analyzed 147 patients who underwent mpMRI before prostate biopsy because of elevated serum prostate-specific antigen and/or abnormal digital rectal examination findings at Korea University Hospital, Seoul, Korea from March 2017 to April 2018. Regions on the mpMRI that were suggestive of prostate cancer were categorized according to the Prostate Imaging–Reporting and Data System (PI-RADS v2). For transperineal biopsy, a 20-core saturation biopsy was performed by MRI-TRUS cognitive or fusion techniques and a 12-core biopsy was performed in transrectal biopsy. RESULTS: Sixty-three and 84 patients were enrolled in transperineal group and transrectal group, respectively. The overall detection rate of prostate cancer in transperineal group was 27% higher than that in transrectal group. Classification according to PI-RADS score revealed a significant increase in detection rate in all patients, as the PI-RADS score increased. Frequency of complications using the Clavien-Dindo classifications revealed no significant differences in the total complications rate, but two patients in transrectal group received intensive care unit care due to urosepsis. CONCLUSIONS: Our results confirmed that transperineal biopsy is superior to transrectal biopsy for the detection of prostate cancer. From the complication point of view, this study confirmed that there were fewer severe complications in transperineal biopsy.

Oncologic Outcomes and Predictive Factors for Recurrence Following Robot-Assisted Radical Cystectomy for Urothelial Carcinoma: Multicenter Study from Korea

The aim of our study was to evaluate intermediate-term oncologic outcomes, predictive factors for recurrence, and recurrence patterns in a multicenter series of patients treated with robot-assisted radical cystectomy (RARC) for urothelial carcinoma (UC) of the bladder. Between 2007 and 2015, 346 patients underwent RARC at multiple tertiary referral centers in Korea. Descriptive statistics were used for demographics and perioperative variables. Survival and recurrence were estimated with Kaplan-Meier analysis. Logistic regression models were used to determine predictors of recurrence. Median follow-up was 33 months (interquartile range [IQR], 7–50). The numbers of patients with organ-confined and lymph node (LN)-positive disease were 237 (68.4%) and 68 (19.7%), respectively. LN density (1–20 vs. > 20) was 13.6% and 6.1%, with a median of 17 nodes removed (IQR, 9–23). In logistic regression analysis, type of LN dissection, and pathologic tumor stage were significant predictors of cancer recurrence and death from cancer. Local, distal recurrence and secondary UC occurred in 7 (2.0%), 53 (15.3%), and 4 (1.2%) patients, respectively. The 5-year overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) were 78%, 84%, and 73%, respectively. At last follow-up, RFS for extended pelvic LN dissection vs. standard pelvic LN dissection was 70% and 47% (P = 0.038). In addition, at last follow-up, LN density (0 vs. 1–20 vs. over 20) was 67%, 41%, and 29%, respectively (P < 0.001). Patients undergoing RARC in this multi-institutional cohort demonstrated intermediate-term oncologic outcomes, predictive factors for recurrence, and recurrence patterns that were not unusual.

Systemic sclerosis due to crystalline silica exposure among jewelry workers in Korea: two case reports

BACKGROUND: Occupational exposure to crystalline silica is a potential risk factor for various systemic autoimmune diseases including systemic sclerosis. The etiology of systemic sclerosis is not conclusively known, but there are epidemiological studies that show the relationship between exposure to crystalline silica and risk of systemic sclerosis. Here we report, for the first time, two cases of crystalline silica-related systemic sclerosis in patients who worked in crystal processing in the jewelry-manufacturing field. CASE PRESENTATION: Case 1 is a 57-year-old man who had worked mainly in crystal processing for multiple jewelry-processing companies for 17 years, since the age of 15 years. He contracted tuberculosis at the age of 25 years and showed Raynaud's phenomenon of both the hands and feet at age 32 years. Digital cyanosis and sclerosis developed at approximately age 41 years. The patient was diagnosed with systemic sclerosis at age 48 years. Case 2 is a 52-year-old man who worked in crystal processing for various jewelry-processing companies for 7 years, since the age of 23 years. He first showed signs of cyanosis in the third and fourth digits of both hands at age 32 years, was diagnosed with Raynaud's syndrome at age 37 years, and was diagnosed with systemic sclerosis at age 38 years. Crystal processing is a detailed process that involves slabbing and trimming the selected amethyst and quartz crystals, which requires close proximity of the worker's face with the target area. In the 1980s and 1990s, the working hours were 12 h per day, and the working environment involved 15 workers crowded into a small, 70-m2 space with poor ventilation. CONCLUSION: Two workers who processed crystals with a maximum crystalline silica content of 56.66% developed systemic sclerosis. Considering the epidemiological and experimental evidence, exposure to crystalline silica dust was an important risk factor for systemic sclerosis. An active intervention is necessary to reduce exposure in similar exposure groups in the field of jewelry processing.

Cases of acute mercury poisoning by mercury vapor exposure during the demolition of a fluorescent lamp factory

BACKGROUND: In 2015, workers dismantling a fluorescent lamp factory in Korea were affected by mercury poisoning from exposure to mercury vapor. CASE PRESENTATION: Eighteen out of the 21 workers who participated in the demolition project presented with symptoms of poisoning and, of these, 10 had persistent symptoms even at 18 months after the initial exposure to mercury vapor. Early symptoms of 18 workers included a general skin rash, pruritus, myalgia, sleep disturbance, and cough and sputum production. Following alleviation of these initial symptoms, late symptoms, such as easy fatigue, insomnia, bad dreams, and anxiety disorder, began to manifest in 10 out of 18 patients. Seven workers underwent psychiatric care owing to sleep disturbance, anxiety disorder, and depression, and three workers underwent dermatologic treatment for hyperpigmentation, erythematous skin eruption, and chloracne-like skin lesions. Furthermore, three workers developed a coarse jerky movement, two had swan neck deformity of the fingers, and two received care at an anesthesiology clinic for paresthesia, such as burning sensation, cold sensation, and pain. Two workers underwent urologic treatment for dysfunction of the urologic system and impotence. However, symptomatic treatment did not result in satisfactory relief of these symptoms. CONCLUSION: Awareness of the perils of mercury and prevention of mercury exposure are critical for preventing health hazards caused by mercury vapor. Chelation therapy should be performed promptly following mercury poisoning to minimize damage.

Emphysema prevalence related air pollution caused by a cement plant

BACKGROUND: To identify adverse pulmonary health effects due to air pollution derived from a cement plant in Korea. The emphysema prevalence in residents around a cement plant was compared to that in the group who live far away from the plant by chest films (PA and lateral view) and high-resolution computed tomography (HRCT) lung images. METHODS: From June to August in 2013 and from August to November in 2014, chest films and HRCT scan were conducted on residents over the age of 40 who lived around a cement plant. The residents were divided into two groups; a “more exposed group (MEG)” which consisted of 1,046 people who lived within a 1 km radius and a “less exposed group (LEG)” which consisted of 317 people who lived more than 5 km away from the same plant. We compared the emphysema prevalence and estimated the OR of this between the MEG and the LEG by using a chi-square and logistic regression on chest films and HRCT. RESULTS: The emphysema prevalence was 9.1 % in the LEG, 14.3 % in the MEG on chest films and 11.4 %, 17.8 % on the HRCT, respectively. The OR of the emphysema prevalence in MEG was 2.92 (95 % CI 1.77-4.83) on the chest films, 2.56 (95 % CI 1.64–3.99) on the HRCT after sex, age, body mass index (BMI), smoking history, residency period and firewood used history were adjusted. The OR in the less than 29 pack-years smoking history was 1.66 (95 % CI 0.92–3.06) and in the more than 30 pack-years was 3.05 (95 % CI 1.68–5.52) on the chest films, and was 1.68 (95 % CI 0.98–2.90), 2.93 (95 % CI 1.72–4.98) on the HRCT, respectively. CONCLUSION: The emphysema prevalence seems to be affected by the level of exposure to air pollution derived from the cement plant as well as sex, age, BMI, and smoking history in this study. Moreover, the OR of the case of the more exposed to the air pollution was similar to that of the case in smoking.