Coexistence of Posterior Cortical Atrophy and Parkinson’s Disease

We report a rare and unique presentation of a patient with early and levodopa-responsive Parkinson’s disease (PD) who exhibited clinical features similar to posterior cortical atrophy (PCA). The imaging evidence suggested the coexistence of PD and PCA, without the presence of amyloid pathology. Although the present case lacks pathologic evidence, this case represents a distinct manifestation of PD characterized by a combination of parkinsonism and early prominent posterior cognitive deficits, reminiscent of the visual variant of Alzheimer’s disease.

Isolation of High Purity Mouse Mesenchymal Stem Cells through Depleting Macrophages Using Liposomal Clodronate

BACKGROUND@#The use of mouse bone marrow mesenchymal stem cells (mBMSCs) represents a promising strategy for performing preclinical studies in the field of cell-based regenerative medicine; however, mBMSCs obtained via conventional isolation methods have two drawbacks, i.e., (i) they are heterogeneous due to frequent macrophage contamination, and (ii) they require long-term culturing for expansion. @*METHODS@#In the present study, we report a novel strategy to generate highly pure mBMSCs using liposomal clodronate.This approach is based on the properties of the two cell populations, i.e., BMSCs (to adhere to the plasticware in culture dishes) and macrophages (to phagocytose liposomes). @*RESULTS@#Liposomal clodronate added during the first passage of whole bone marrow culture was selectively engulfed by macrophages in the heterogeneous cell population, resulting in their effective elimination without affecting the MSCs.This method allowed the generation of numerous high-purity Sca-1 ＋ CD44 ＋ F4/80 - mBMSCs ([ 95%) with just one passaging. Comparative studies with mBMSCs obtained using conventional methods revealed that the mBMSCs obtained in the present study had remarkably improved experimental utilities, as demonstrated by in vitro multilineage differentiation and in vivo ectopic bone formation assays. @*CONCLUSION@#Our newly developed method, which enables the isolation of mBMSCs using simple and convenient protocol, will aid preclinical studies based on the use of MSCs.

Bone Generation Following Repeated Administration of Recombinant Bone Morphogenetic Protein 2

BACKGROUND@#The delivery of recombinant human bone morphogenetic protein 2 (rhBMP2) by using various carriers has been used to successfully induce bone formation in many animal models. However, the effect of multiple administration of rhBMP2 on bone formation and BMP2 antibody production has not been determined. Our aim was to examine the bone formation activity of rhBMP2 and serum levels of anti-BMP2 antibodies following the repeated administration of rhBMP2 in mice. @*METHODS@#Absorbable collagen sponges or polyphosphazene hydrogels containing rhBMP2 were subcutaneously implanted or injected into one side on the back of six-week-old C57BL/6 mice. Three or 4 weeks later, the same amount of rhBMP2 was administered again with the same carrier into the subcutaneous regions on the other side of the back or into calvarial defects. The effects of a single administration of rhBMP2 on the osteoinductive ability in the ectopic model were compared with those of repeated administrations. In vivo ectopic or orthotopic bone formation was evaluated using microradiography and histological analyses. Serum concentrations of anti-rhBMP2 antibodies were measured by ELISAs. @*RESULTS@#Re-administration of the same amount of rhBMP2 into the subcutaneous area showed a comparable production of ectopic bone as after the first administration. The bone forming ability of repeated rhBMP2 administrations was equal to that of single rhBMP2 administration. The administration of rhBMP2 into calvarial defects, following the first subcutaneous administration of rhBMP2 on the back, completely recovered the defect area with newly regenerated bone within 3 weeks. Repeated administration of rhBMP2 at 4-week intervals did not significantly alter the serum levels of antiBMP2 antibodies and did not induce any inflammatory response. The serum obtained from rhBMP2-exposed mice had no effect on the ability of rhBMP2 to induce osteogenic gene expressions in MC3T3-E1. @*CONCLUSION@#We suggest that the osteoinductive ability of rhBMP2 is not compromised by repeated administrations. Thus, rhBMP2 can be repeatedly used for bone regeneration at various sites within a short duration.

Bone Generation Following Repeated Administration of Recombinant Bone Morphogenetic Protein 2

BACKGROUND@#The delivery of recombinant human bone morphogenetic protein 2 (rhBMP2) by using various carriers has been used to successfully induce bone formation in many animal models. However, the effect of multiple administration of rhBMP2 on bone formation and BMP2 antibody production has not been determined. Our aim was to examine the bone formation activity of rhBMP2 and serum levels of anti-BMP2 antibodies following the repeated administration of rhBMP2 in mice. @*METHODS@#Absorbable collagen sponges or polyphosphazene hydrogels containing rhBMP2 were subcutaneously implanted or injected into one side on the back of six-week-old C57BL/6 mice. Three or 4 weeks later, the same amount of rhBMP2 was administered again with the same carrier into the subcutaneous regions on the other side of the back or into calvarial defects. The effects of a single administration of rhBMP2 on the osteoinductive ability in the ectopic model were compared with those of repeated administrations. In vivo ectopic or orthotopic bone formation was evaluated using microradiography and histological analyses. Serum concentrations of anti-rhBMP2 antibodies were measured by ELISAs. @*RESULTS@#Re-administration of the same amount of rhBMP2 into the subcutaneous area showed a comparable production of ectopic bone as after the first administration. The bone forming ability of repeated rhBMP2 administrations was equal to that of single rhBMP2 administration. The administration of rhBMP2 into calvarial defects, following the first subcutaneous administration of rhBMP2 on the back, completely recovered the defect area with newly regenerated bone within 3 weeks. Repeated administration of rhBMP2 at 4-week intervals did not significantly alter the serum levels of antiBMP2 antibodies and did not induce any inflammatory response. The serum obtained from rhBMP2-exposed mice had no effect on the ability of rhBMP2 to induce osteogenic gene expressions in MC3T3-E1. @*CONCLUSION@#We suggest that the osteoinductive ability of rhBMP2 is not compromised by repeated administrations. Thus, rhBMP2 can be repeatedly used for bone regeneration at various sites within a short duration.

Mainstreaming of Health Equity in Infectious Disease Control Policy During the COVID-19 Pandemic Era / 예방의학회지

The Korean government’s strategy to combat coronavirus disease 2019 (COVID-19) has focused on non-pharmaceutical interventions, such as social distancing and wearing masks, along with testing, tracing, and treatment; overall, its performance has been relatively good compared to that of many other countries heavily affected by COVID-19. However, little attention has been paid to health equity in measures to control the COVID-19 pandemic. The study aimed to examine the unequal impacts of COVID-19 across socioeconomic groups and to suggest potential solutions to tackle these inequalities. The pathways linking social determinants and health could be entry points to tackle the unequal consequences of this public health emergency. It is crucial for infectious disease policy to consider social determinants of health including poor housing, precarious working conditions, disrupted healthcare services, and suspension of social services. Moreover, the high levels of uncertainty and complexity inherent in this public health emergency, as well as the health and socioeconomic inequalities caused by the pandemic, underscore the need for good governance other than top-down measures by the government. We emphasize that a people-centered perspective is a key approach during the pandemic era. Mutual trust between the state and civil society, strong accountability of the government, and civic participation are essential components of cooperative disaster governance.

Effects of Chin-Down Maneuver on Pharyngeal Pressure Generation According to Dysphagia and Viscosity

Objective@#To demonstrate the effects of chin-down maneuver on swallowing by using high-resolution manometry (HRM). @*Methods@#HRM data of 20 healthy subjects and 64 dysphagic patients were analyzed. Participants swallowed 5 mL of thin and honey-like liquids in neutral and chin-down positions. HRM was used to evaluate maximal velopharyngeal pressure/area, maximal tongue base pressure/area, maximal pharyngeal constrictor pressure, pre-/post-swallow upper esophageal sphincter (UES) peak pressure, minimal UES pressure, UES activity time, and nadir duration. @*Results@#Compared to the neutral position, the chin-down maneuver significantly increased tongue base pressure in both normal and dysphagic groups as well as for both honey-like and thin viscosities, although the honey-like liquid did not reach statistical significance in the dysphagic group. Regarding pharyngeal constrictors and pre-swallow peak UES pressure, the healthy group showed a significant decrease in thin liquid swallowing and decreasing tendency in honeylike liquid swallowing. UES nadir duration was significantly decreased for honey-like liquid swallowing in the dysphagic group and for both thin and honey-like liquids in the healthy group. UES nadir duration of honey-like and thin flow swallowing in the dysphagia group was 0.26 seconds after the chin-down maneuver, which was severely limited. @*Conclusion@#This study showed a different kinetic effect of the chin-down maneuver between the healthy and dysphagic groups, as well as between thin and honey-like viscosities. The chin-down maneuver increased tongue base pressure and decreased UES nadir duration, which the latter was severely limited in dysphagic patients. Therefore, appropriate application of the chin-down maneuver in clinical practice is required.

Effects of Chin-Down Maneuver on Pharyngeal Pressure Generation According to Dysphagia and Viscosity

Objective@#To demonstrate the effects of chin-down maneuver on swallowing by using high-resolution manometry (HRM). @*Methods@#HRM data of 20 healthy subjects and 64 dysphagic patients were analyzed. Participants swallowed 5 mL of thin and honey-like liquids in neutral and chin-down positions. HRM was used to evaluate maximal velopharyngeal pressure/area, maximal tongue base pressure/area, maximal pharyngeal constrictor pressure, pre-/post-swallow upper esophageal sphincter (UES) peak pressure, minimal UES pressure, UES activity time, and nadir duration. @*Results@#Compared to the neutral position, the chin-down maneuver significantly increased tongue base pressure in both normal and dysphagic groups as well as for both honey-like and thin viscosities, although the honey-like liquid did not reach statistical significance in the dysphagic group. Regarding pharyngeal constrictors and pre-swallow peak UES pressure, the healthy group showed a significant decrease in thin liquid swallowing and decreasing tendency in honeylike liquid swallowing. UES nadir duration was significantly decreased for honey-like liquid swallowing in the dysphagic group and for both thin and honey-like liquids in the healthy group. UES nadir duration of honey-like and thin flow swallowing in the dysphagia group was 0.26 seconds after the chin-down maneuver, which was severely limited. @*Conclusion@#This study showed a different kinetic effect of the chin-down maneuver between the healthy and dysphagic groups, as well as between thin and honey-like viscosities. The chin-down maneuver increased tongue base pressure and decreased UES nadir duration, which the latter was severely limited in dysphagic patients. Therefore, appropriate application of the chin-down maneuver in clinical practice is required.

Child Safety Injury Experiences, Prevention Behaviors and Educational Needs among Immigrant Vietnamese Women on Jeju Island

PURPOSE: Study purpose was to describe the child safety injury experiences, injury prevention behaviors and educational needs of immigrant Vietnamese women on Jeju Island, and to explore associations among those factors.METHODS: A descriptive correlational study was conducted using structured questionnaires to collect data from immigrant Vietnamese women who visited a multicultural centers on Jeju Island from January to April, 2017.RESULTS: Data from 60 women were analyzed. They were 28.2±5.5 years old, had resided in Korea for 40.6±31.1 months, and had 1.5±0.6 children on average. In total, 51.7% had previous injury prevention education, 68.2% had experienced child safety injuries, and 95.0% wanted to receive education on how to prevent child safety injuries. The mean total score of child injury prevention behaviors was 27.33±17.79, and that variable was associated with a longer duration of formal education (t=2.41, p=.021) and with women's experiences of child safety injury (t=5.97, p<.001).CONCLUSION: Immigrant Vietnamese women experienced a higher frequency of child safety injuries and needed educational opportunities to prevent these injuries. Further research is necessary to develop the essential content and effective methods for education on child safety injury prevention among this unique multicultural population.

CCR5 deficiency in aged mice causes a decrease in bone mass

The CC chemokine receptor 5 (CCR5) is a G protein-coupled receptor that regulates chemotaxis and effector functions of immune cells. It also serves as the major co-receptor for the entry of human immunodeficiency virus (HIV). Recently, CCR5 inhibitors have been developed and used for the treatment or prevention of HIV infections. Additionally, it has been identified that CCR5 controls bone homeostasis by regulating osteoclastogenesis and the communication between osteoblasts and osteoclasts. However, the effects of CCR5 inhibition on bone tissue in elderly patients are unknown. This study aimed to examine the bone phenotype of aged CCR5 knockout (KO) mice. Femoral and tibial bones were isolated from 12-month and 18-month old wild-type (WT) and CCR5 KO mice, and microcomputed tomography and histology analyses were performed. Twelve-month-old CCR5 KO mice exhibited a decreased trabecular bone mass and cortical bone thickness in both femoral and tibial bones compared with age-matched WT mice. Eighteen-month-old mice also showed a decreased trabecular bone mass in femurs compared with control WT mice, but not in tibial bones. Unlike in 12-month-old mice, the cortical margin of femurs and tibias in 18-month-old mice were rough, likely because they were aggravated by the deficiency of CCR5. Overall, our data suggest that the deficiency of CCR5 with aging can cause severe bone loss. When CCR5 inhibitors or CCR5 inactivating technologies are used in elderly patients, a preventive strategy for bone loss should be considered.

A cross-sectional study on the pulmonary function of residents in two urban areas with different PM10 concentrations: data from the fourth Korea national health and nutrition examination survey (KNHANES) 2007–2009

BACKGROUND: The present study aims to compare the pulmonary function of residents of Seoul special city (Seoul) and Jeju special self-governing province including Jeju city and Seogwipo city (Jeju), characterized by vastly different annual average airborne particulate matter with an aerodynamic diameter less ≤10 μm (PM10) concentrations, with the annual average PM10 concentration in Seoul being significantly higher than that in Jeju. METHODS: This cross-sectional study analyzed the pulmonary function test results and sociodemographic data of Korean adults ≥19 years of age derived from the 4th KNHANES, 2007–2009. A total of 830 individuals residing in Seoul or Jeju were included in this study. T-tests were used to analyze predicted values of forced expiratory volume in 1 sec (FEV1p), predicted values of forced vital capacity (FVCp) and FEV1/FVC ratio (FEV1/FVC), as dependent variables, to examine the differences in the subjects’ pulmonary function according to the city of residence. Stratified analysis was then performed to adjust for variables potentially affecting pulmonary function. The analysis was performed on subjects as a group and also following stratification according to sex and other variables. RESULTS: Seoul residents had a significantly lower FVCp than that of the Jeju residents (difference: 3.48%, p = 0.002). FEV1p, FVCp and FEV1/FVC of male Seoul residents were significantly lower than those of male Jeju residents (difference: 6.99, 5.11% and 0.03, respectively; p < 0.001, p = 0.001, p = 0.001). In male subjects, statistically significant results were obtained even after adjusting the influence of other variables through stratified analysis. CONCLUSION: The present analysis was based on cross-sectional data collected at one point in time. Therefore, unlike longitudinal studies, it does not establish a clear causal association between the variables. Nevertheless, this study found that pulmonary function among subjects residing in Seoul was significantly decreased compared to that of subjects residing in Jeju.

Quantitative Analysis of Tooth Mineral Content by High Resolution Micro-computed Tomography

Teeth and bones are highly mineralized tissues containing inorganic minerals such as calcium phosphate, and a growing number of evidences show that their mineral content is associated with many diseases. Although the quantification of mineral contents by micro-computed tomography(micro- CT) has been used in diagnosis and evaluation for treating bone diseases, its application for teeth diseases has not been well established. In this study, we attempted to estimate a usefulness of a high-resolution micro-CT in analysis of human teeth. The teeth were scanned by using the Skyscan 1172 micro-CT. In order to measure tooth mineral content, beam hardening effect of the machine was corrected with a radiopaque iodinecontaining substance, iodoacetamide. Under the maximum resolution of 6.6 µm, X-ray densities in teeth and hydroxyapatite standards were obtained with Hounsfield unit (HU), and they were then converted to an absolute mineral concentration by a CT Analyzer software. In enamel layer of cusp area, the mean mineral concentration was about 2.14 mg/mm³ and there was a constant mineral concentration gradient from the enamel surface to the dentinoenamel junction. In the dentin of middle 1/3 of tooth, the mean mineral concentration was approximately 1.27 mg/mm³ and there was a constant mineral concentration gradient from the outer of root to the pulp side, ranging from 1.3 to 1.06 mg/mm³. In decay region of dentin, the mineral content was gradually decreased from the intact inner side to the decayed surface. These results suggest that high-resolution micro-CT can be as a useful tool for non-invasive measurement of mineral concentration in teeth.

Association between supervisors' behavior and wage workers' job stress in Korea: analysis of the fourth Korean working conditions survey

BACKGROUND: In modern society, many workers are stressed. Supervisors' support or behavior can affect the emotional or psychological part of the worker. The purpose of this study is to investigate the effect of supervisor's behavior on worker's stress. METHODS: The study included 19,272 subjects following the assignment of weighted values to workers other than soldiers using data from the Fourth Korean Working Condition Survey. Supervisors' behavior was measured using 5 items: “supervisor feedback regarding work,”“respectful attitude,”“good conflict-resolution ability,”“good work-related planning and organizational ability,” and the encouragement of participation in important decision making. Job stress was measured using 1 item: “I experience stress at work.” Multiple logistic regression analysis was performed to examine the effects of supervisors' behavioral, general, occupational, and psychosocial characteristics on job stress in workers. Organizational characteristics associated with supervisors' behavior were also analyzed. RESULTS: The results showed that supervisors' provision of feedback regarding work increased workers' job stress (OR = 1.329, 95% CI = 1.203 ~ 1.468). When a supervisor respect workers (OR = 0.812, 95% CI = 0.722 ~ 0.913) or good at planning and organizing works (OR = 0.816, 95% CI: 0.732 ~ 0.910), workers' job stress decreased. In particular, the two types of supervisor behaviors, other than feedback regarding work, were high in private-sector organizations employing less than 300 employees. CONCLUSION: Supervisors' behavior influenced job stress levels in workers. Therefore, it is necessary to increase education regarding the effects of supervisors' behavior on job stress, which should initially be provided in private-sector organizations with up to 300 employees.

Clinical evaluation of mandibular implant overdentures via Locator implant attachment and Locator bar attachment

PURPOSE: The aim of this study was to evaluate the clinical findings and patient satisfaction on implant overdenture designed with Locator implant attachment or Locator bar attachment in mandibular edentulous patients. MATERIALS AND METHODS: Implant survival rate, marginal bone loss, probing depth, peri-implant inflammation, bleeding, plaque, calculus, complications, and satisfaction were evaluated on sixteen patients who were treated with mandibular overdenture and have used it for at least 1 year (Locator implant attachment: n=8, Locator bar attachment: n=8). RESULTS: Marginal bone loss, probing depth, plaque index of the Locator bar attachment group were significantly lower than the Locator implant attachment group (P.05). The replacement of the attachment components was the most common complication in both groups. Although there was no correlation between marginal bone loss and plaque index, a significant correlation was found between marginal bone loss and probing depth. CONCLUSION: The Locator bar attachment group indicates lesser marginal bone loss and need for maintenance, as compared with the Locator implant attachment group. This may be due to the splinting effect among implants rather than the types of Locator attachment.

A Preliminary Study for the Development of the Elderly Smoking Cessation Program : Focus on the Expectancy, Self-Efficacy and Accessing Cognitive Functions

OBJECTIVE: This study aimed to investigate the smoking behavior and attitude about smoking cessation of elderly and to evaluate the effect of accessing cognitive function in order to develop the cessation program for elderly smokers. METHODS: The participants were 108 enrolled from attending the cessation program of national non-smoking guide center. We examined the Smoking Cessation Motivation Scale, The Perceived Smoking Cessation Effects Scale (PSCES), Smoking selfefficacy/temptation, The Why test and Tobacco Craving Questionnaire. Cognitive status was ascertained by interviewing with geriatric neuropsychiatrist and comprehensive neurocognitive test battery. RESULTS: The older group had lower negative effect score of PSCES (52.0±17.7, 61.3±16.6, p=0.006) and higher smoking self-efficacy score (29.4±7.2, 26.0±8.3, p=0.028) than younger group. 47.1% of older group and 12.3% of younger group were mild cognitive impairment (p<0.001). The success rate of smoking cessation after 12 weeks was 92.2% in older group and 91.2% in younger group (p=1.00). CONCLUSION: The results indicate that the smoking cessation of elderly is not so challenge otherwise known as. Although the prevalence of mild cognitive impairment in smokers was higher than the general population, cognitive assessment and feedback might be made of the high success rate of smoking cessation. Further attention should be paid to the elderly tailored smoking cessation program and long-term follow-up.

Characteristics and Surgical Outcome of Macular Holes Developing after Rhegmatogenous Retinal Detachment Repair

PURPOSE: To report the characteristics and surgical outcome of macular holes (MHs) that develop after rhegmatogenous retinal detachment (RRD) repair. METHODS: A retrospective chart review was performed in patients who developed a new full-thickness macular hole after RRD repair between May 2010 and July 2013. For eyes that underwent pars plana vitrectomy with internal limiting membrane peeling and gas tamponade for MH repair, main outcomes included macular attachment status and postoperative visual acuity. RESULTS: Fourteen full-thickness MHs were detected in a series of 2,815 eyes (0.49% prevalence) that had undergone prior RRD surgery. Ten MHs developed after primary vitrectomy and four after scleral bucking surgery. The fovea was detached in eight of the 14 eyes at the time of RRD. Fourteen of 14 eyes were managed by pars plana vitrectomy, internal limiting membrane peeling, and intravitreal gas tamponade, and 12 of 14 eyes achieved MH closure. Mean preoperative Snellen best-corrected visual acuity (BCVA) was 20/63 (+/-0.25). Nine of 14 eyes had an improvement in visual acuity of at least two Snellen lines, and five eyes remained unchanged. CONCLUSIONS: In this small retrospective study, the secondary MHs were found predominantly in foveal detachments after RRD repair, most commonly occurring after primary vitrectomy. In conclusion, the surgical outcome and postoperative visual acuity improvement were satisfactory, although the final BCVA depended on the macular status during the RRD.

Expression of DNA Repairing Enzymes in the Cerebral Tissue of the Rat Fetus After Hypoxic Injury / 체질인류학회지

Hypoxia is one of the major causes of neonatal mortality. Hypoxia-induced tissue injuries are resulted from complex mechanisms such as DNA damage and apoptosis. In this study, we aimed to elucidate the changes in the expression of DNA repairing enzymes such as 8-hydroxyguanine glycosylase 1 (OGG1) and apurinic/apyrimidinic endonuclease 1 (APE1) and brain derived neurotrophic factor (BDNF) in the fetal cerebral tissue after intrauterine hypoxic injury. For this study, pregnant Sprague-Dawley rats were exposed to hypoxic gas (10% O2, 5% CO2, 85% N2) for 2 or 4 hours at postconception day 14.5 and 15.5. After 24 hours, the animals were anesthetized with ethyl ether and fetuses were obtained by laparatomy. Hematoxylin-eosin stain, immunohistochemical stain, and western blot were employed for analysis. The caspase-3 immunolabeled cells were significantly increased within the cerebral cortex after hypoxic injury. The expressions of OGG1, APE1, and BDNF were also increased in the cerebral tissue after hypoxic injury at post-conception day 14.5, in a dose-dependent manner. However, the expression of BDNF was significantly decreased in the cortical tissue exposed to hypoxic injury at postconception day 15.5. These results demonstrate that fetal hypoxic injury induces apoptosis of the nerve cells and promotes the expressions of the DNA repairing enzymes and neurotrophic factors. In addition, these results suggest that protection mechanisms against hypoxic injury alter along the progression of the fetal development.

Nail DNA and Possible Biomarkers: A Pilot Study / 예방의학회지

OBJECTIVES: Nail has been a substitute DNA source for genotyping. To investigate the integrity and consistency of nail DNA amplification for biomarker study, nail clippings from 12 subjects were collected at monthly intervals. The possibility of longer amplification and existence of GAPDH RNA/protein, were also investigated with three nail samples. METHODS: Three primer sets were designed for quantitative amplification of nuclear and mitochondrial genes and analysis of their consistency. The mean threshold cycles in amplification of the target genes were compared to test the consistency of polymerase chain reaction (PCR) performance among individual factors including age groups, sex, family, the nail source, and by the size of the amplification segments. RESULTS: The amplification of the target genes from nail DNA showed similar integrity and consistency between the nail sources, and among the serial collections. However, nail DNA from those in their forties showed earlier threshold cycles in amplification than those in their teens or seventies. Mitochondrial DNA (mtDNA) showed better DNA integrity and consistency in amplification of all three targets than did nuclear DNA (nucDNA). Over 9 kb of mtDNA was successfully amplified, and nested quantitative PCR showed reliable copy numbers (%) between the two loci. Reverse transcription PCR for mRNA and immunoblotting for GAPDH protein successfully reflected their corresponding amounts. Regarding the existence of RNA and protein in nails, more effective extraction and detection methods need to be set up to validate the feasibility in biomarker study. CONCLUSIONS: Nail DNA might be a feasible intra-individual monitoring biomarker. Considering integrity and consistency in target amplification, mtDNA would be a better target for biomarker research than nucDNA.

Results of Arthroscopic Debridement of the Elbow Osteoarthritis

PURPOSE: Primary osteoarthritis on the elbow is the result of the growth of osteophytes and contracture of the capsule. It often causes disability on joint motion and pain while exercising. As arthroscopy has developed, the arthroscopic diagnosis and treatment of the elbow have recently become more generalized as well. Therefore, we like to report on arthroscopy for treating elbow arthritis and its results. MATERIALS AND METHODS: This study includes 23 cases of elbow arthritis that were seen between 2005 June to 2007 June and these patients didn't response to conservative treatment. From this we excluded 18 cases that underwent arthroscopic surgery and among these 18 cases, 6 cases underwent ulnar nerve transfer. The average observation time was 21.3 months and the average age was 48.4 years (range: 22-66 years). The pre and post operative pain was evaluated with using the Visual Analogue Scale (VAS) and functional evaluation was done with using the Mayo elbow Performance Score (MEPS) with the range of joint motion. RESULTS: The VAS score at the last follow up was significantly decreased from 3.4 to 1.9 compare to the preoperative score. The range of joint motion was improved by 25 (0-40) to 8.5 (0-20) in extension and 101.7 (80-140) to 125.2 (85-140) in flexion (p<0.05). The MEPS always showed significant improvement by showing an increase from 65.4 (40-85) to 87.9 (55-100). However, 3 cases showed a decreased range of motion after the operation. One case showed ulnar nerve symptoms after surgery. CONCLUSION: An arthroscopic procedure can treat the pathologic processes associated with arthritis of the elbow and it was safe and effective in this series.

Three-dimensional finite element analysis for the effect of retentive groove design on joint strength of casting connection / 대한치과보철학회지

STATEMENT OF PROBLEM: A casting connection technique is widely used for repair, correction and addition to base metal framework. However, a casting connection technique may increase the risk of failure in clinical situations when high stresses exist. PURPOSE: The purpose of this study was to investigate the mechanical retentive groove design comparatively to increase the joint strength by using the three-dimensional finite element analysis model of a 3-unit fixed partial denture. MATERIAL AND METHODS: Ten finite element models were constructed. (Model A: One retentive groove, Model B: Two retentive grooves, Model C: Three retentive grooves, Model D: Four retentive grooves, Model E: One horizontal groove and two vertical grooves, Model F: Two horizontal grooves and one vertical groove, Model G: One groove with the enlarged dimension, Model H: Two grooves with the enlarged dimension, Model I: One groove with the increased height, Model J: One groove with the increased width of base). The vertical force was applied to the mesial and the distal fossa to the casting connection of mandibular first molar. RESULTS: The main factors, affecting joint strength of casting connection were both the retention between the primary cast and the secondary cast and the thickness of the primary cast remaining after preparing retentive groove. The increase of retentive force, according to the numbers and the dimension of retentive groove had an effect on distributing stress. However, in some cases, the increase of retentive force resulted in the increase of stress by reducing thickness of the primary cast in the connection area. CONCLUSION: The design of retentive groove that limits number of retentive groove for metal thickness and increases the depth of retentive groove for retention is highly recommended.

Treatment of Upper Thoracic Disc Herniation Using Transthoracic Approach without Division of Latissimus Dorsi: Technical Note / 대한척추외과학회지

Thoracic disc herniation is a rare condition in which a posterior approach, extrapleural approach, posterolateral approach, or transthoracic approach is currently used. The posterior approach is not recommended in thoracic disc herniation surgery because of the risk of spinal cord injury. The transthoracic approach makes it possible to remove the intervertebral disc and is considered a standard method. However, due to an extensive transverse skin incision, division of the latissimus dorsi muscles, and rib resection, the conventional open approaches involve a risk of complications, such as infection and post-thoracotomy pain syndrome; and a long period of rehabilitation and recovery is required. Excision of the intervertebral disc under thoracoscopic guidance can reduce the damage to the skin and muscles, but the equipment and surgical materials are expensive and a long learning curve is required. Therefore, we report a case and a new muscle splitting transthoracic approach that can be performed by incising 10 cm of skin longitudinally and preserving the serratus anterior and latissimus dorsi muscles.