PURPOSE: To determine the anatomical characteristic of C-shaped canal systems in Korean mandibular 2nd molars by cone beam computed tomography (CBCT). MATERIALS AND METHODS: The 824 CBCT images were evaluated. These patients were taken CBCT for the diagnosis and treatment of dental implantation on 2013. The 711 mandibular 2nd molars were examined. The configuration of root canal systems were classified according to modified Melton's classifications. RESULTS: Of the 711 mandibular 2nd molars, 21.5% had C-shaped canal systems. This prevalence did not differ with tooth position. Most of the C-shaped canals with bilateral molars were symmetrical. Of the C-shaped canal, the most common configuration Type were Melton's Type I (89%) in the orifice level and Melton's III (83.8%) in the apical level. The prevalence of C-shaped canal was higher in female (25%) than male (13.9%) (P < 0.05). CONCLUSION: A high prevalence of C-shaped canals were observed in Korean mandibular 2nd molars. For successful C-shaped root canal treatment, the comprehension of root canal systems was important.
Classification ; Comprehension ; Cone-Beam Computed Tomography* ; Dental Implantation ; Dental Implants ; Dental Pulp Cavity* ; Diagnosis ; Female ; Humans ; Male ; Molar* ; Prevalence ; Tooth

In adult spinal deformity (ASD) surgery, mechanical failure (MF) has been a significant concern for spine surgeons as well as patients. Despite earnest endeavors to prevent MF, the absence of a definitive consensus persists, owing to the intricate interplay of multifarious factors associated with this complication. Previous approaches centered around global spinal alignment have yielded limited success in entirely forestalling MF. These methodologies, albeit valuable, exhibited limitations by neglecting to encompass global balance and compensatory mechanisms within their purview. In response to this concern, an in-depth comprehension of global balance and compensatory mechanisms emerges as imperative. In this discourse, the center of gravity and the gravity line are gaining attention in recent investigations pertaining to global balance. This narrative review aims to provide an overview of the global balance and a comprehensive understanding of related concepts and knowledge. Moreover, it delves into the clinical ramifications of the contemporary optimal correction paradigm to furnish an encompassing understanding of global balance and the current optimal correction strategies within the context of ASD surgery. By doing so, it endeavors to furnish spine surgeons with a guiding compass, enriching their decision-making process as they navigate the intricate terrain of ASD surgical interventions.

PURPOSE: The cDNA microarray has become a useful tool for observing the expression of thousands of genes simultaneously. However, obtaining good quality microarray data is not easy due to the inherent noise at various stages of the experiment. Therefore, it is essential to understand the source of the variation in the microarray experiment and its size as an initial step of the data analyses. MATERIALS AND METHODS: The total RNA extracted from HT-1080 fibrosarcoma and normal rat tissues were hybridized to the cDNA microarrays with 0.5 K human and 5 K rat genes, respectively. A homotypic reaction and dye swap experiments were used to identify the sources of the variation. RESULTS: The relative fluorescent intensities of the microarray, if unnormalized, have a large variation, particularly in the lower intensity region. The distribution of the log intensity ratios also exhibit some departure from a band around zero, which is the distribution pattern expected when the majority of genes in the microarray are not regulated. Normalization of the log ratios is usually required as a means of preprocessing the data. We claim that a within-print tip group, an intensity-dependent normalization through a loess fit adjustment will be useful for this purpose, particularly in the initial stages of the microarray experiment. CONCLUSION: For proper data analysis, an understanding the source of the variation and preprocessing of data with a suitable normalization method will be important. It is important to have an interactive cooperation between a researcher and a statistician from the early stages of the study design and to the final stages of data analysis.
Animals ; DNA, Complementary* ; Fibrosarcoma ; Humans ; Noise ; Oligonucleotide Array Sequence Analysis* ; Rats ; RNA ; Statistics as Topic

BACKGROUND AND OBJECTIVES: Candesartan cilexetil (Atacand ), a selective type I angiotensin II receptor blocker, has recently been introduced as a new antihypertensive agent. We evaluated its anti-hypertensive effect and safety in mild to moderate hypertensive patients. MATERIALS AND METHODS: Candesartan cilexetil, 8 mg or 16 mg, was administered once a day over 8 weeks period in the patients with mild to moderate hypertension (25 male, 26 female, mean age: 53.5+/-1.2 years). For safety evaluation, laboratory tests were performed before and after treatment with candesartan cilexetil. Changes in blood pressure, heart rate and electrocardiogram were also observed. RESULTS: 1) The mean blood pressures in the sitting position were systolic 164.1+/-2.1 mmHg and diastolic 106.3+/-0.8 mmHg before treatment, which were lowered to 135.4+/-2.0 mmHg and 89.1+/-1.1 mmHg, repectively after 8 weeks of treatment (p<0.05). 2) Candesartan cilexetil had a significant dose-dependent antihypertensive effect for diastolic pressure in 35 patients (8 mg: 97.8+/-0.9 mmHg, 16 mg: 91.3+/-1.1 mmHg, p<0.05). 3) Heart rate was not significantly changed before and after treatment during the treatment with candesartan cilexetil (72.2+/-1.2/min vs. 72.0+/-1.3/min: p>0.05). 4) Laboratory tests revealed no significant abnormality by the treatment with candesartan cilexetil. 5) Left ventricular hypertrophy by ECG criteria detected in 3 cases disappeared after treatment with candesartan cilexetil. 6) No significant side effects were observed during the treatment period. CONCLUSION: Candesartan cilexetil, 8 mg or 16 mg, once a day is an effective and well tolerated antihypertensive treatment. It has a significant dose-dependent antihypertensive effect.
Blood Pressure ; Electrocardiography ; Female ; Heart Rate ; Humans ; Hypertension ; Hypertrophy, Left Ventricular ; Male ; Receptors, Angiotensin

C2–3 disc herniation is rare and a definitive treatment of choice has not been established.The purpose of this case report is to suggest posterior approach as one of the best options.A 49-year-old man visited our clinic with a 7-year history of neck pain and occipital headache and a 2-month history of right arm pain. C2–3 intervertebral disc herniation of the central type was diagnosed on magnetic resonance imaging (MRI), and surgery was performed, including C1 laminectomy, C2–3 laminoplasty, and C2–3 posterior fixation. The posterior approach was used because the patient's neck was difficult to operate anteriorly. After 3 months postoperatively, MRI showed widened cerebrospinal fluid space at the C2–3 level.The visual analogue scale score for pain improved in the occipital area and right arm.However, the untouched protruded central disc, subjective weakness in right hand grasping, and numbness persisted. In conclusion, this case highlights posterior decompression and fixation as a good treatment of choice for decompression at the C2–3 level disc herniation, from where it is difficult to remove compressive lesions directly via the anterior corridor.

Active and prompt scale-up screening tests are essential to efficiently control the coronavirus disease 2019 (COVID-19) outbreak. The goal of this work was to identify shortcomings in the conventional screening system (CSS) implemented in the beginning of the outbreak. To overcome these shortcomings, we then introduced a novel, independently developed system called the Yeungnam University type drive-through (YU-Thru), and distributed it nationwide in Korea. This system is similar to the drive-throughs utilized by fast food restaurants. YU-Thru system has shortened the time taken to test a single person to 2–4 minutes, by completely eliminating the time required to clean and ventilate the specimen collection room. This time requirement was a major drawback of the CSS. YU-Thru system also reduced the risk of subjects and medical staff infecting one another by using a separate and closed examination system. On average, 50 to 60 tests were conducted per day when using the CSS, while now up to 350 tests per day are conducted with the YU-Thru system. We believe that the YU-Thru system has made an important contribution to the rapid detection of COVID-19 in Daegu, South Korea. Here, we will describe the YU-Thru system in detail so that other countries experiencing COVID-19 outbreaks can take advantage of this system.

OBJECTIVE: There is a traditional assumption that to maximize stroke volume, the point beneath which the left ventricle (LV) is at its maximum diameter (P_max.LV) should be compressed. Thus, we aimed to derive and validate rules to estimate P_max.LV using anteroposterior chest radiography (chest_AP), which is performed for critically ill patients urgently needing determination of their personalized P_max.LV.METHODS: A retrospective, cross-sectional study was performed with non-cardiac arrest adults who underwent chest_AP within 1 hour of computed tomography (derivation:validation=3:2). On chest_AP, we defined cardiac diameter (CD), distance from right cardiac border to midline (RB), and cardiac height (CH) from the carina to the uppermost point of left hemi-diaphragm. Setting point zero (0, 0) at the midpoint of the xiphisternal joint and designating leftward and upward directions as positive on x- and y-axes, we located P_max.LV (x_max.LV, y_max.LV). The coefficients of the following mathematically inferred rules were sought: x_max.LV=α₀*CD-RB; y_max.LV=β₀*CH+γ₀ (α₀: mean of [x_max.LV+RB]/CD; β₀, γ₀: representative coefficient and constant of linear regression model, respectively).RESULTS: Among 360 cases (52.0±18.3 years, 102 females), we derived: x_max.LV=0.643*CD-RB and y_max.LV=55-0.390*CH. This estimated P_max.LV (19±11 mm) was as close as the averaged P_max.LV (19±11 mm, P=0.13) and closer than the three equidistant points representing the current guidelines (67±13, 56±10, and 77±17 mm; all P<0.001) to the reference identified on computed tomography. Thus, our findings were validated.CONCLUSION: Personalized P_max.LV can be estimated using chest_AP. Further studies with actual cardiac arrest victims are needed to verify the safety and effectiveness of the rule.
Adult ; Cardiopulmonary Resuscitation ; Critical Illness ; Cross-Sectional Studies ; Heart Arrest ; Heart Ventricles ; Humans ; Intensive Care Units ; Joints ; Linear Models ; Radiography ; Radiography, Thoracic ; Retrospective Studies ; Stroke Volume ; Thorax ; Tomography, X-Ray Computed

Background: Although total knee arthroplasty (TKA) is considered an effective treatment for knee osteoarthritis, it carries risks of complications. With a growing number of TKAs performed on older patients, understanding the cause of mortality is crucial to enhance the safety of TKA. This study aimed to identify the major causes of short- and long-term mortality after TKA and report mortality trends for major causes of death. Methods: A total of 4,124 patients who underwent TKA were analyzed. The average age at surgery was 70.7 years. The average follow-up time was 73.5 months. The causes of death were retrospectively collected through Korean Statistical Information Service and classified into 13 subgroups based on the International Classification of Diseases-10 code. The short- and long-term causes of death were identified within the time-to-death intervals of 30, 60, 90, 180, 180 days, and > 180 days. Standard mortality ratios (SMRs) and cumulative incidence of deaths were computed to examine mortality trends after TKA. Results: The short-term mortality rate was 0.07% for 30 days, 0.1% for 60 days, 0.2% for 90 days, and 0.2% for 180 days. Malignant neoplasm and cardiovascular disease were the main short-term causes of death. The long-term (> 180 days) mortality rate was 6.2%. Malignant neoplasm (35%), others (11.7%), and respiratory disease (10.1%) were the major long-term causes of death.Men had a higher cumulative risk of death for respiratory, metabolic, and cardiovascular diseases. Age-adjusted mortality was significantly higher in TKA patients aged 70 years (SMR, 4.3; 95% confidence interval [CI], 3.3–5.4) and between 70 and 79 years (SMR 2.9; 95% CI, 2.5–3.5) than that in the general population. Conclusions The short-term mortality rate after TKA was low, and most of the causes were unrelated to TKA. The major causes of long-term death were consistent with previous findings. Our findings can be used as counseling data to understand the survival and mortality of TKA patients.

Objective: Peritonitis is a life-threatening, emergent surgical disease with very high mortality and morbidity. Currently, there are insufficient Korean studies using the P-POSSUM (Portsmouth-Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity) and the Mannheim Peritonitis Index (MPI) as risk prediction models for nontraumatic peritonitis patients who visit the emergency room. Methods: This retrospective study was carried out on 196 cases of non-traumatic peritonitis in a single emergency center from January 2015 to December 2019. Receiver operating characteristic (ROC) curves were obtained and the area under the ROC curve (AUC) was compared using both P-POSSUM and MPI. The observed mortality and expected mortality for P-POSSUM were compared using the goodness of fit assessed using the Hosmer-Lemeshow equation. Results: Diastolic blood pressure, blood urea nitrogen, potassium, length of stay, and intensive care unit admissions were significantly different between survivors and non-survivors. The AUC was 0.812 for P-POSSUM and 0.646 for MPI. The observed-to-expected mortality ratio for P-POSSUM indicated fewer than expected deaths in all quintiles of risk and this was more pronounced, especially when the expected mortality was over 60%. Conclusion In non-traumatic peritonitis patients, P-POSSUM was more useful in predicting risk than the MPI score. However, P-POSSUM overestimated the risk in high-risk patients. Although the MPI score is only somewhat useful for predicting mortality in patients with non-traumatic peritonitis, it is useful as an adjuvant.

PURPOSE: Our aim was to evaluate the efficacy and safety of oral beclomethasone dipropionate (BDP) in Korean patients with ulcerative colitis (UC). MATERIALS AND METHODS: The medical records of patients with active UC who were treated with BDP were retrospectively reviewed. Partial Mayo Clinic score (pMS) was calculated to determine disease activity. After 4 weeks of therapy, clinical remission, clinical response, and response failure rates were evaluated. Clinical remission was defined as a post-treatment pMS of 0 or 1, clinical response as a decrease of two of three points in pMS and >30% from baseline, and response failure as a lack of clinical response. Also, we considered that clinical remission was included in clinical response. RESULTS: Between July 2013 and April 2015, 95 patients with UC received BDP therapy at our institution (median age, 44 years; range, 12–81 years). After 4 weeks of therapy, clinical remission and clinical response rates were 50.5% and 73.7%, respectively. Mean change of pMS before and after BDP therapy was 2.4. There was no significant side effect reported. In multivariate analysis, disease activity was the only factor associated with a favorable response. Clinical remission rate was significantly higher in the mild disease activity group (66.7%) than that in the moderate or severe disease activity group (41.9%) (p=0.024). CONCLUSION: BDP is efficacious in inducing a clinical response or remission in Korean patients with UC. Patients with mild UC were more likely to be in remission than those with moderate or severe UC after receiving BDP for 4 weeks. BDP exhibited a good safety profile.
Administration, Oral ; Anti-Inflammatory Agents/*administration & dosage/adverse effects ; Beclomethasone/*administration & dosage/adverse effects ; Colitis, Ulcerative/drug therapy ; Drug-Related Side Effects and Adverse Reactions ; Female ; Humans ; Male ; Medical Records ; Remission Induction ; Republic of Korea ; Retrospective Studies ; Safety ; Treatment Outcome ; Young Adult