Effect of coronavirus disease 2019 pandemic on children’s visits to the emergency department

Purpose@#In the coronavirus disease 2019 pandemic, it is essential to supplement the changes in visiting patterns of individual emergency departments (EDs) to determine how to allocate emergency medicine resources. We compared the clinical features of children visiting the ED before and during the pandemic. @*Methods@#Children younger than 18 years who visited the ED from February 2019 through December 2020, except January 2020, were enrolled, and divided into those who visited before and after January 2020 (the pre-pandemic and pandemic groups, respectively). We compared the 2 groups in terms of the baseline characteristics (age, sex, mode and route of arrival, cause of visit, and time of visit), chief complaint, ED diagnosis, initial acuity and its accuracy, and ED outcomes (length of stay and disposition). @*Results@#The 31,036 children were categorized into the pre-pandemic (21,027 [67.8%]) and pandemic (10,009 [32.2%]) groups with a 52.4% decrease in the number of visits to the ED in the latter group. This decrease was more prominent in age 2-5 years (from 37.3% to 33.2%; P < 0.001), fever as a chief complaint (from 27.8% to 16.5%), diagnoses related to infection or the respiratory system (from 36.8% to 14.3%) or transfer to the ED (from 8.1% to 6.4%; P < 0.001). In contrast, increases were noted in age 12-17 years (from 14.9% to 17.4%; P < 0.001), injury (from 36.5% to 52.5%; P < 0.001), visits in the evening (from 54.9% to 57.4%; P < 0.001), length of stay longer than 6 hours (from 3.5% to 6.3%; P = 0.033), and low acuity (from 97.8% to 98.2%; P = 0.031). @*Conclusion@#The pandemic has brought about changes in visiting patterns of the ED. This study may help prepare strategies for the appropriate allocation and deployment of emergency medicine resources in the pandemic era.

Validation and modification of HEART score components for patients with chest pain in the emergency department

Objective@#This study aimed to clarify the relative prognostic value of each History, Electrocardiography, Age, Risk Factors, and Troponin (HEART) score component for major adverse cardiac events (MACE) within 3 months and validate the modified HEART (mHEART) score. @*Methods@#This study evaluated the HEART score components for patients with chest symptoms visiting the emergency department from November 19, 2018 to November 19, 2019. All components were evaluated using logistic regression analysis and the scores for HEART, mHEART, and Thrombolysis in Myocardial Infarction (TIMI) were determined using the receiver operating characteristics curve. @*Results@#The patients were divided into a derivation (809 patients) and a validation group (298 patients). In multivariate analysis, age did not show statistical significance in the detection of MACE within 3 months and the mHEART score was calculated after omitting the age component. The areas under the receiver operating characteristics curves for HEART, mHEART and TIMI scores in the prediction of MACE within 3 months were 0.88, 0.91, and 0.83, respectively, in the derivation group; and 0.88, 0.91, and 0.81, respectively, in the validation group. When the cutoff value for each scoring system was determined for the maintenance of a negative predictive value for a MACE rate >99%, the mHEART score showed the highest sensitivity, specificity, positive predictive value, and negative predictive value (97.4%, 54.2%, 23.7%, and 99.3%, respectively). @*Conclusion@#Our study showed that the mHEART score better detects short-term MACE in high-risk patients and ensures the safe disposition of low-risk patients than the HEART and TIMI scores.

Cluster Analysis of Inhalant Allergens in South Korea: A Computational Model of Allergic Sensitization

Objectives@#. Sensitization to specific inhalant allergens is a major risk factor for the development of atopic diseases, which impose a major socioeconomic burden and significantly diminish quality of life. However, patterns of inhalant allergic sensitization have yet to be precisely described. Therefore, to enhance the understanding of aeroallergens, we performed a cluster analysis of inhalant allergic sensitization using a computational model. @*Methods@#. Skin prick data were collected from 7,504 individuals. A positive skin prick response was defined as an allergen-to-histamine wheal ratio ≥1. To identify the clustering of inhalant allergic sensitization, we performed computational analysis using the four-parameter unified-Richards model. @*Results@#. Hierarchical cluster analysis grouped inhalant allergens into three clusters based on the Davies-Bouldin index (0.528): cluster 1 (Dermatophagoides pteronyssinus and Dermatophagoides farinae), cluster 2 (mugwort, cockroach, oak, birch, cat, and dog), and cluster 3 (Alternaria tenus, ragweed, Candida albicans, Kentucky grass, and meadow grass). Computational modeling revealed that each allergen cluster had a different trajectory over the lifespan. Cluster 1 showed a high level (>50%) of sensitization at an early age (before 19 years), followed by a sharp decrease in sensitization. Cluster 2 showed a moderate level (10%–20%) of sensitization before 29 years of age, followed by a steady decrease in sensitization. However, cluster 3 revealed a low level (<10%) of sensitization at all ages. @*Conclusion@#. Computational modeling suggests that allergic sensitization consists of three clusters with distinct patterns at different ages. The results of this study will be helpful to allergists in managing patients with atopic diseases.

Application of convolutional neural networks for distal radio-ulnar fracture detection on plain radiographs in the emergency room

Objective@#Recent studies have suggested that deep-learning models can satisfactorily assist in fracture diagnosis. We aimed to evaluate the performance of two of such models in wrist fracture detection. @*Methods@#We collected image data of patients who visited with wrist trauma at the emergency department. A dataset extracted from January 2018 to May 2020 was split into training (90%) and test (10%) datasets, and two types of convolutional neural networks (i.e., DenseNet-161 and ResNet-152) were trained to detect wrist fractures. Gradient-weighted class activation mapping was used to highlight the regions of radiograph scans that contributed to the decision of the model. Performance of the convolutional neural network models was evaluated using the area under the receiver operating characteristic curve. @*Results@#For model training, we used 4,551 radiographs from 798 patients and 4,443 radiographs from 1,481 patients with and without fractures, respectively. The remaining 10% (300 radiographs from 100 patients with fractures and 690 radiographs from 230 patients without fractures) was used as a test dataset. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of DenseNet-161 and ResNet-152 in the test dataset were 90.3%, 90.3%, 80.3%, 95.6%, and 90.3% and 88.6%, 88.4%, 76.9%, 94.7%, and 88.5%, respectively. The area under the receiver operating characteristic curves of DenseNet-161 and ResNet-152 for wrist fracture detection were 0.962 and 0.947, respectively. @*Conclusion@#We demonstrated that DenseNet-161 and ResNet-152 models could help detect wrist fractures in the emergency room with satisfactory performance.

Application of convolutional neural networks for distal radio-ulnar fracture detection on plain radiographs in the emergency room

Objective@#Recent studies have suggested that deep-learning models can satisfactorily assist in fracture diagnosis. We aimed to evaluate the performance of two of such models in wrist fracture detection. @*Methods@#We collected image data of patients who visited with wrist trauma at the emergency department. A dataset extracted from January 2018 to May 2020 was split into training (90%) and test (10%) datasets, and two types of convolutional neural networks (i.e., DenseNet-161 and ResNet-152) were trained to detect wrist fractures. Gradient-weighted class activation mapping was used to highlight the regions of radiograph scans that contributed to the decision of the model. Performance of the convolutional neural network models was evaluated using the area under the receiver operating characteristic curve. @*Results@#For model training, we used 4,551 radiographs from 798 patients and 4,443 radiographs from 1,481 patients with and without fractures, respectively. The remaining 10% (300 radiographs from 100 patients with fractures and 690 radiographs from 230 patients without fractures) was used as a test dataset. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of DenseNet-161 and ResNet-152 in the test dataset were 90.3%, 90.3%, 80.3%, 95.6%, and 90.3% and 88.6%, 88.4%, 76.9%, 94.7%, and 88.5%, respectively. The area under the receiver operating characteristic curves of DenseNet-161 and ResNet-152 for wrist fracture detection were 0.962 and 0.947, respectively. @*Conclusion@#We demonstrated that DenseNet-161 and ResNet-152 models could help detect wrist fractures in the emergency room with satisfactory performance.

Central Venous Catheterization before Versus after Computed Tomography in Hemodynamically Unstable Patients with Major Blunt Trauma: Clinical Characteristics and Factors for Decision Making

PURPOSE@#When hemodynamically unstable patients with blunt major trauma arrive at the emergency department (ED), the safety of performing early whole-body computed tomography (WBCT) is concerning. Some clinicians perform central venous catheterization (CVC) before WBCT (pre-computed tomography [CT] group) for hemodynamic stabilization. However, as no study has reported the factors affecting this decision, we compared clinical characteristics and outcomes of the pre- and post-CT groups and determined factors affecting this decision.@*METHODS@#This retrospective study included 70 hemodynamically unstable patients with chest or/and abdominal blunt injury who underwent WBCT and CVC between March 2013 and November 2017.@*RESULTS@#Univariate analysis revealed that the injury severity score, intubation, pulse pressure, focused assessment with sonography in trauma positivity score, and pH were different between the pre-CT (34 patients, 48.6%) and post-CT (all, p < 0.05) groups. Multivariate analysis revealed that injury severity score (ISS) and intubation were factors affecting the decision to perform CVC before CT (p=0.003 and p=0.043). Regarding clinical outcomes, the interval from ED arrival to CT (p=0.011) and definite bleeding control (p=0.038), and hospital and intensive care unit lengths of stay (p=0.018 and p=0.053) were longer in the pre-CT group than in the post-CT group. Although not significant, the pre-CT group had lower survival rates at 24 hours and 28 days than the post-CT group (p=0.168 and p=0.226).@*CONCLUSIONS@#Clinicians have a tendency to perform CVC before CT in patients with blunt major trauma and high ISS and intubation.

Estimation of Nurse Staffing Based on Nursing Workload with Reference to a Patient Classification System for a Intensive Care Unit / 중환자간호학회지

PURPOSE: This study aimed to estimate the appropriate nurse staffing ratio in intensive care units (ICUs) by measuring nursing workload based on patient's severity and needs, using the Korean Patient Classification System for critical care nurses.METHODS: The data were collected from January 18 to February 29, 2016 using a standardized checklist by observation or self-report. During the study period, 723 patients were included to be categorized from I to IV using the patient classification system. Measurement of total nursing workload on a shift was calculated in terms of hours based on the time and motion method by using tools for surveying nursing activities. The nursing activities were categorized as direct nursing care, indirect nursing care, and personal time. Total of 127 cases were included in measuring direct nursing time and 18 nurses participated in measuring indirect and personal time. Data were analyzed using descriptive statistics.RESULTS: Two patients were classified into Class I (11.1%), 5 into Class II (27.8%), 9 into Class III (50%), and two into Class IV (11.1%). The amount of direct nursing care required for Class IV (513.7 min) was significantly more than that required for Class I (135.4 min). Direct and indirect nursing care was provided more often during the day shift as compared to the evening or night shifts. These findings provided the rationale for determining the appropriate ratio for nursing staff per shift based on the nursing workload in each shift.CONCLUSIONS: An appropriate ratio of nurse staffing should be ensured in ICUs to re-arrange the workload of nurses to help them provide essential direct care for patients.

The Ability of the Acute Physiology and Chronic Health Evaluation (APACHE) IV Score to Predict Mortality in a Single Tertiary Hospital / 대한구급학회지

BACKGROUND: The Acute Physiology and Chronic Health Evaluation (APACHE) II model has been widely used in Korea. However, there have been few studies on the APACHE IV model in Korean intensive care units (ICUs). The aim of this study was to compare the ability of APACHE IV and APACHE II in predicting hospital mortality, and to investigate the ability of APACHE IV as a critical care triage criterion. METHODS: The study was designed as a prospective cohort study. Measurements of discrimination and calibration were performed using the area under the receiver operating characteristic curve (AUROC) and the Hosmer-Lemeshow goodness-of-fit test respectively. We also calculated the standardized mortality ratio (SMR). RESULTS: The APACHE IV score, the Charlson Comorbidity index (CCI) score, acute respiratory distress syndrome, and unplanned ICU admissions were independently associated with hospital mortality. The calibration, discrimination, and SMR of APACHE IV were good (H = 7.67, P = 0.465; C = 3.42, P = 0.905; AUROC = 0.759; SMR = 1.00). However, the explanatory power of an APACHE IV score >93 alone on hospital mortality was low at 44.1%. The explanatory power was increased to 53.8% when the hospital mortality was predicted using a model that considers APACHE IV >93 scores, medical admission, and risk factors for CCI >3 coincidentally. However, the discriminative ability of the prediction model was unsatisfactory (C index <0.70). CONCLUSIONS: The APACHE IV presented good discrimination, calibration, and SMR for hospital mortality.

The Ability of the Acute Physiology and Chronic Health Evaluation (APACHE) IV Score to Predict Mortality in a Single Tertiary Hospital / 대한중환자의학회지

BACKGROUND: The Acute Physiology and Chronic Health Evaluation (APACHE) II model has been widely used in Korea. However, there have been few studies on the APACHE IV model in Korean intensive care units (ICUs). The aim of this study was to compare the ability of APACHE IV and APACHE II in predicting hospital mortality, and to investigate the ability of APACHE IV as a critical care triage criterion. METHODS: The study was designed as a prospective cohort study. Measurements of discrimination and calibration were performed using the area under the receiver operating characteristic curve (AUROC) and the Hosmer-Lemeshow goodness-of-fit test respectively. We also calculated the standardized mortality ratio (SMR). RESULTS: The APACHE IV score, the Charlson Comorbidity index (CCI) score, acute respiratory distress syndrome, and unplanned ICU admissions were independently associated with hospital mortality. The calibration, discrimination, and SMR of APACHE IV were good (H = 7.67, P = 0.465; C = 3.42, P = 0.905; AUROC = 0.759; SMR = 1.00). However, the explanatory power of an APACHE IV score >93 alone on hospital mortality was low at 44.1%. The explanatory power was increased to 53.8% when the hospital mortality was predicted using a model that considers APACHE IV >93 scores, medical admission, and risk factors for CCI >3 coincidentally. However, the discriminative ability of the prediction model was unsatisfactory (C index <0.70). CONCLUSIONS: The APACHE IV presented good discrimination, calibration, and SMR for hospital mortality.

Clinical Features of Acute Aortic Dissection Patients Initially Diagnosed with ST-segment Elevation Myocardial Infarction

PURPOSE: Acute myocardial infarction (AMI) concomitant with acute aortic syndrome (AAS) is rare but prompt recognition of concomitant AAS is critical, particularly in patients with ST-segment elevation myocardial infarction (STEMI) because misdiagnosis with early thrombolytic or anticoagulant treatment may result in catastrophic consequences. This study examined the clinical features of patients of STEMI concomitant with AAS that may be a diagnostic clue. METHODS: Between January 1, 2010 and December 31, 2014, 22 patients who had the initial diagnosis of acute coronary syndrome (AMI and unstable angina) and AAS (aortic dissection, intramural hematoma, and ruptured thoracic aneurysm) in our emergency department were reviewed. Among them, 10 patients who were transferred from other hospitals and 4 patients with non-STEMI were excluded, leaving 8 patients of STEMI concomitant with AAS for analysis. RESULTS: The mean age of study patients was 57.5+/-16.31 years and five patients were Stanford type A and three patients were type B aortic dissection. Six patients had ST-segment elevation in anterior leads and 2 patients in inferior leads. Most patients had acute onset and severe chest pain, but none had dissecting nature chest pain. Serum troponin I was elevated in three patients but all patients had Ddimer elevation. Aortic regurgitation or regional wall motion abnormality was detected in four patients, and widened mediastinum was observed in all study patients. CONCLUSION: Concomitant AAS might be suspected in patients with STEMI who have elevated D-dimer and widened mediastinum.

Fetal Heart Rate Regresses toward the Mean in the Third Trimester

The purpose of this study was to investigate the feasibility of different fetal heart rate (FHR) ranges in the nonstress test (NST) and to better understand the meaning of mild bradycardia and/or tachycardia without non-reassuring patterns. We employed the heredity to show that mild bradycardia (100-119 beats per minute, bpm) and mild tachycardia (161-180 bpm) regressed to the normal FHR range (120-160 bpm). We used linear regression to analyze FHR data from FHR tracings recorded 10 min before (NST, as the predictor) and 10 min after vibroacoustic stimulation testing (as the dependent variable). Acceleration for 15 bpm-15 seconds (Acc1515) and deceleration for 15 bpm-15 seconds (Dec1515) in the NST were also analyzed for each group. The slope of the best-fit line was the largest in the mild bradycardia group and the smallest in the normal range group. Dec1515 was most prominent in mild tachycardia and both the mild bradycardia and tachycardia groups regressed towards the mean FHR range. Therefore, we propose that both mild bradycardia and tachycardia of FHR in non-acute situations (range between 100 and 180 bpm) are not regarded a pathologic signal for clinical use.

Predictors for Subjective Memory Complaints in the Elderly: The Results from Korean Longitudinal Study on Health and Aging (KLoSHA) / 신경정신의학

OBJECTIVES: We investigated the predictors of subjective memory complaints in the community-dwelling normal elderly. METHODS: This study was conducted as a part of Korean Longitudinal Study on Health and Aging (KLoSHA). 747 nondemented community-dwelling elderly aged 65 years or older were recruited. All participants underwent clinical evaluation for dementia and psychiatric disorder conformed to the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) Clinical Assessment Battery and Korean version of Mini-International Neuropsychiatric Interview, respectively. Word list recall test, frontal assessment battery, Mini Mental Status Examination (MMSE-KC) and Korean version of Geriatric depression scale (GDS-K) were administered to evaluate episodic memory, frontal function, global cognition and depression, respectively. Subjective memory complaint was defined in two different ways: worse than one's past (SMC-P) and worse than others of one's age (SMC-O). RESULTS: In highly educated elderly, minor depressive disorder (OR=7.23, 95% C.I.= 2.29-22.86) and frontal dysfunction (OR=2.48, 95% C.I.=1.29-4.77) significantly increased the risk of SMC-O. However, they did not influence the risk of SMC-P. In low educated elderly, both the minor depressive disorder and frontal dysfunction did not influence the risk of SMC-O as well as that of SMC-P. CONCLUSION: SMC-O can be a sensitive subjective recognition of mild depression and/or frontal dysfunction in highly educated normal elderly.

Meta Analysis of Clinical Studies of Pregnancy and Delivery in Elderly Gravida / 대한산부인과학회지

OBJECTIVE: Our purpose was to identify the age-related inceased risks of the elderly gravida over 35 or 40 years at delivery by clarifying the effects of age and parity, their combination, and their interaction and the relationships of other complications. METHODS: We have made meta analysis about general and clinical characteristics of elderly gravida over the aged 35 or 40 years, based on the 7 domestic theses since 1996 year at the department of Obstetrics and Gynecology. RESULTS: The results were obtained as follows; In elderly gravida over the aged 35 or 40 years at delivery, maternal and neonatal outcomes were generally good, but in study group, there were a high incidence of gestational (preterm delivery, fetal presentation, pregnancy-induced hypertension, gestational diadetes, placenta previa, premature rupture of membranes) complications, uterine myoma during pregnancy and low birth weight in neonate after delivery. CONCLUSION: The increased risks of the elderly gravida over the aged 35 or 40 years at delivery may have been overshadowed by the previous focus on the elderly nullipara. In spite of high incidence of maternal morbidity, the overall maternal and neonatal outcomes were generally good. It is important to recognize what is more important in age-related pregnant-risks of the elderly gravida over the aged 35 or 40 years at delivery to appropriate counsel and manage this group of patients. This informations may be helpful for counsel in elderly gravida over the aged 35 or 40 years who are considering pregnancy.

A clinical study on the change of aluminium in a blood of the chronic renal failure patients undergoing hemodialysis / 대한내과학회지

BACKGROUND: More than 25 years have been passed since Korea started the hemodialysis. Initially, the technical problems of dialysis machine, a handling of azotemia, sustained anemia, as well as renal osteodystrophy were major matters we have to solve, however, recently the focused matters were changed that the removal of heavier molecular weighed uremic toxins, toxins like aluminium and silicon are very important, because these toxins are hardly removed and are very influential on the uremic signs. In this study, we planned to observe how much aluminium accumulated in chronic hemodialysis patients, and how much significant is increased aluminium blood level in patients. METHODS: We randomly selected fifty patients undergoing chronic hemodialysis to estimate the serum level of aluminium. We analyzed patients by using clinical informations, such as the time period of hemodialysis, the dialysis frequency, whether diabetes or not , according to the aluminium serum levels. The aluminium serum levels were estimated before and after the hemodialysis, which were measured by using the atomic absorption spectrophotometry. RESULTS: The serum levels of aluminium in CRF patients undergoing hemodialysis were significantly increased, as compared with normal range and much more increased levels was observed after hemodialysis 48.9+/-3.2 microgram/L than before 27.6+/-2.3 microgram/L (p<0.05) (Table 2). The aluminium level before hemodialysis of diabetic patients (40.3+/-17.6 microgram/L) showed I.57 times higher than non-diabetes (25.7+/-21.2 microgram/L), but the level after hemodialysis showed non-significant difference (Figure 1). The aluminium blood level after hemodialysis and the duration of hemodialysis were correlated positively (r=0.34, p<0.01), but this wasn't before hemodialysis (Figure 2). The serum level of aluminium tends upward following to increasing level of serum calcium, serum magnesium, as well as parathyroid hormone (Table 3). The delta aluminium(post-pre dialysis) level was significantly correlated positively (r=0.66, p<0.05) with delta Hb (post-pre dialysis) level (Figure 3). CONCLUSION: The serum level of aluminium in chronic renal failure patients undergoing hemodialysis were significantly increased and especially, more increased as soon as the hemodialysis was finished.

The Relationship between Weight-Bearing and Stiff-Knee Gait in Hemiplegic Patients

OBJECTIVE: To determine whether insufficient weight-bearing on the hemiparetic side has a correlation with the degree of stiff-knee gait in hemiplegic patients. METHOD: Fifty hemiplegic patients were included. In all patients, 3-dimensonal gait analysis and static and dynamic foot pressure measurements were taken. The degree of stiff-knee gait was evaluated using the peak knee flexion angle and the knee flexion slope at toe-off in hemiplegic limb. The degree of weight-bearing was evaluated using the percentage of hemiplegic foot pressure and pressure-time integration on the non-hemiplegic side. RESULTS: The static and dynamic mean pressure ratios and pressure-time integration ratio were statistically correlated with peak knee flexion angle and knee flexion slope (p<0.01). CONCLUSION: As a result, insufficient weight-bearing had a correlation with the degree of stiff-knee gait in hemiplegic patients. Insufficient weight-bearing should be further investigated to determine whether it is one of the characteristic findings of stiff-knee gait, or another cause of stiff-knee gait.

The Changes of Aquaporin-2 Expression in Rats with Lithium Induced Nephrogenic Diabetes Insipidus after Hydrochlorothiazide Administration / 대한신장학회잡지

BACKGROUND: Thiazides have been used in nephrogenic diabetes insipidus (NDI) patients to decrease urine volume, but the mechanism of antidiuretic effect is not known yet. Recently, it has been demonstrated that abundance of aquaporin-2 (AQP2) was decreased in lithium induced NDI. We performed this study to investigate the effect of hydrochlorothiazide (HCTZ) in lithium induced NDI rats and the change of AQP2 expression. METHODS: NDI was induced in 7 male Spraque- Dawley rats by feeding lithium carbonate containing rat chow (40 mmol/kg) for 5 weeks. 4 rats were control group. HCTZ 3.75 mg/day (n=3 among lithium treated; Li+TZ) or vehicle (n=4 among lithium treated and control; Li and Control, respectively) was infused to the rats through osmotic minipump for the last 7 days. Urine volume and urine osmolality were measured. Kidneys were processed for immunohistochemistry and immunoblotting using antibody to AQP2. RESULTS: Li+TZ showed decreased urine volume (46+/-11 mL/day for Li+TZ vs. 127+/-1 mL/day for Li, p<0.05) and higher urine osmolality (557+/-139 mmol/kgH2O for Li+TZ vs. 207+/-9 mmol/kgH2O for Li, p<0.05) comparing to Li. In semi-quantitative immunoblotting using whole kidney homogenate, Li+TZ showed increase in AQP2 expression comparing to Li (39+/-2% for Li+TZ vs. 20+/-9% for Li, p<0.05, % of normal controls). In immunohistochemistry, AQP2 expression in cortex was markedly decreased after lithium treatment. But, AQP2 expression was slightly increased after HCTZ treatment. CONCLUSION: HCTZ treatment partially increased urine concentrating ability and AQP2 expression in rats with lithium induced NDI. We concluded that partial improvement in urine concentrating ability might be associated with upregulation of AQP2.

A study on fitness of several domestic implant fixture and abutment screws / 대한치과보철학회지

STATEMENT OF PROBLEM: Several domestic dental implants have been developed since dental treatment being implants are increasing and popularized. However, they have not been used in domestic market like imported goods. MATERIAL AND METHODS: This study was carried out to compare domestic and imported implants in aspect of fitness, dental implant fixture and abutment screw using scanning electron microscope. All experiments were performed under dry condition. RESULTS: 1. Only in aspect of relation of dental implant fixture and abutment screw, except only one group with point contact, good fitness was existed. 2. Home products must presevere in their efforts, so as excellent to fit.

Clinical Characteristics of Poor Responders to Erythropoietin among ESRD Patients Undergoing Hemodialysis / 대한신장학회잡지

BACKGROUND: The main pathogenic factor causing anemia in chronic renal failure is the erythropoietin deficiency. However, there are some patients showing poor responses to erythropoietin administration. The purposes of this study were to analyze the clinical parameters of poor responders to erythropoietin among ESRD patients undergoing hemodialysis, and to clarify the major potential factors accounting for poor responses to erythropoietin therapy. METHODS: Eighty-one patients with end-stage renal failure undergoing hemodialysis were included in this study. Poor responders to erythropoietin, defined as patients requiring erythropoietin doses more than 200 U/kg/week subcutaneously to correct anemia, were identified. The hematocrit, erythropoietin dose, erythropoietin resistance index (ERI), and other clinical parameters in 77 patients requiring erythropoietin administration were evaluated and analyzed. RESULTS: Poor responses to erythropoietin were found in 16 patients (20.8%) among 77 patients requiring erythropoietin administration. Serum iron, total iron binding capacity (TIBC), transferrin saturation (TSAT), and albumin concentration were significantly decreased (p or =0.5 mg/dL) was more frequent in poor responders (p<0.01). The independent factor affecting on ERI was TIBC (R=0.44, p<0.01). However, there were no significant difference between poor and good responders in age, gender, duration of dialysis, underlying renal disease, use of ACE inhibitor, dose of dialysis (Kt/V), serum parathyroid hormone, and aluminum concentration. CONCLUSION: TIBC seems to be a predicting factor accounting for poor response to erythropoietin among ESRD patients undergoing hemodialysis.

Chronic Furosemide Administration Alters Abundance of Sodium Transporters in Rat Kidney / 대한신장학회잡지

BACKGROUND: Furosemide inhibit NaCl absorption in the thick ascending limb and produce an increase in distal delivery of Na+. We carried out semiquantitative immunoblotting and immunohistochemistry of rat kidneys to investigate whether chronic furosemide infusion is associated with compensatory increases in the abundance of Na+ transporters in distal nephron. METHODS: Osmotic minipumps were implanted into Sprague-Dawley rats to deliver 12 mg/day of furosemide(n=6) with simultaneous administration of 0.8% NaCl and 0.1% KCl in drinking water for 7 days. RESULTS: Compared with vehicle infused controls, urine volume and urine sodium amount were increased. However, there were no differences in body weight, serum aldosterone, and creatinine clearance. The abundance of Na+-K+-2Cl- cotransporter after furosemide infusion was increased in cortex (151+/-10 vs. 100+/-10%, p< 0.05) and outer medulla (122+/-5 vs. 100+/-3%, p< 0.01). In furosemide infusion group, the abundance of all three subunits of epithelial sodium channel (ENaC) was increased both in cortex (alpha: 187+/-25 vs. 100+/-17%, p< 0.05; beta: 155+/-8 vs. 100+/-15%, p< 0.05; gamma: 168+/-16 vs. 100+/-9%, p< 0.05) and outer medulla (alpha: 171+/-27 vs. 100+/-17%, p< 0.05; beta: 986+/-91 vs. 100+/-33%, p< 0.01; gamma: 242+/-24 vs. 100+/-22%, p< 0.01). Consistent with these results, ENaC beta-subuint immunohistochemistry showed a remarkable increase in immunoreactivity in the principal cells of collecting ducts with furosemide treatment. CONCLUSION: These increases in the abundance of ENaC protein may account for the generation of diuretic tolerance.

Quantitative Assessment of the Effect of Tizanidine on Spasticity in Stroke Patients

OBJECTIVE: The aims of this study were to evaluate quantitatively the effect of tizanidine on spasticity reduction and to evaluate the effective and tolerable dosage of it in stroke patients. METHOD: A prospective, randomized controlled study was carried out. 24 stroke patients were included and randomly assigned to a control and experimental group. In experimental group, tizanidine was medicated from starting dose of 3 mg/day and titrated up by 3 mg/day increments every 3 days to a maximal dose of 15 mg/day. In both group assessment of spasticity was done by clinical and biomechanical-neurophysiological methods one day before medication (baseline), on 9th and 15th days after medication. Biomechenical-neurophysiological assessment was done through isokinetic dynamometer and BIOPAC system. RESULTS: In control group, no significant changes were found in the degree of spasticity between each assessment. In experimental group, most of the parameters that determine the degree of spasticity revealed the significant reduction of spasticity on the post-medication assessment compared with the baseline assessment (p<0.01). The degree of spasticity reduction was increased with the increase of dosage. The incidence of adverse effect was also increased with the increase of dosage, but tolerable within the dosage of 15 mg/day. CONCLUSION: Tizanidine was effective in reducing spasticity in stroke patients. Its efficacy and adverse effects were dosage-related.