OBJECTIVES: We introduce a novel analysis method of spatio-temporal pattern analysis of EEG. Using it, we presents a results discriminating severe Alzheimer's disease patients from normal subjects. METHOD: To the groups of 10 Alzheimer's disease patients and 10 normal aged subjects, we applied the Karhunen-Loeve decomposition method and observed their principal patterns and time-varying dynamics. RESULTS: First, there was a first primary pattern of the eigenvector in Alzheimer's disease patients that showed opposite polarities at the left and the right hemispheric regions. Second, the Alzheimer's disease patients had significantly different average values of the eigenvector at the left parieto-temporal area than the normal controls did. Third, some Alzheimer's disease patients had one, coherent frequency component in the Fourier amplitude spectrum of the first pattern expansion coefficient. CONCLUSION: Our results suggest that the pathophysiologic site of Alzheimer's dementia may be left temporo-parietal area in brain and further studies need to evaluate whether the spatio-temoral pattern analysis could be used to diagnose Alzheimer's dementia patients.
Alzheimer Disease ; Brain ; Dementia* ; Electroencephalography* ; Humans

PURPOSE: The aim of this study was to analyze the factors affecting the outcomes after surgical treatment of acetabular fractures. MATERIALS AND METHODS: Between January 2000 and December 2012, 106 patients with acetabular fractures were treated with open reduction and internal fixation. We performed a retrospective cohort study to analyze the factors which may influence a patient's prognosis after surgical treatment of an acetabular fracture. The factors examined included age, femoral head injury, fracture type, dislocation, initial displacement, delay to injury-related surgery (in days), and quality of reduction. Additionally, we investigated clinical and radiological outcomes, as well as the development of osteoarthritis. RESULTS: Patients included 85 males (80.2%) and 21 females (18.8%) with a mean age of 50.4 (17-78) years. The mean follow-up period was 2.6 (1-10) years. In a univariable regression analysis, quality of reduction, age, and initial displacement were significantly associated with radiological and clinical outcomes. In a multivariable regression analysis, quality of reduction (P<0.001) and initial displacement (P=0.001) were found to be factors predictive of clinical and radiological outcomes. Additionally, the quality of reduction (P=0.005) was found to be predictive of osteoarthritis development. CONCLUSION: Study results indicated that the quality of reduction was the most important factor influencing the prognosis of patients with acetabular fractures.
Acetabulum* ; Cohort Studies ; Craniocerebral Trauma ; Dislocations ; Female ; Follow-Up Studies ; Humans ; Male ; Methods ; Osteoarthritis ; Prognosis ; Retrospective Studies

BACKGROUND: Motor conduction slowing in diabetic distal symmetrical polyneuropathy (DSP) generally exceeds that in distal axonal polyneuropathy. Additional mechanisms secondary to axonal injury may contribute towards this slowing. However, clinical and pathophysiological significances of motor conduction slowing have been rarely discussed. The purpose of this study is to evaluate the clinical and pathophysiological significance of conduction slowing in DSP. METHODS: We analyzed motor conduction studies of 39 patients with symptomatic painful DSP and 24 patients with asymptomatic painless DSP. Motor conduction studies of 39 patients with amyotrophic lateral sclerosis (ALS) were used as controls for the amplitude-dependent slowing of conduction. Percentages of normal limits were calculated for the compound muscle action potential amplitude (CMAP), distal motor latency (DL), and conduction velocity (CV), and converted to a square root (SQRT) form. The changes of SQRT-DL or SQRT-CV according to SQRT-CMAP changes were plotted and analyzed. RESULTS: Regression analysis showed that DL and CV were amplitude-dependent in both painless DSP and ALS. The changes of DL and CV in painful DSP did not show amplitude-dependency except DL in the lower extremities. CONCLUSIONS: This data supports the hypothesis that the mechanism of slowing is similar in both painless DSP and ALS and results from the loss of large, fast-conducting fibers. Lack of amplitude-dependency of conduction slowing in painful DSP may reflect the combined axonal and demyelinating changes, possibly due to inflammation.
Action Potentials ; Amyotrophic Lateral Sclerosis ; Axons ; Diabetic Neuropathies* ; Electrophysiology ; Humans ; Inflammation ; Lower Extremity ; Neural Conduction ; Polyneuropathies

The objective of this study was to observe the histology of dental pulp healing after tooth replantation in rats. The maxillary right first molars of 4-week-old rat were extracted, and then the teeth were repositioned in the original socket. At 3 days after replantation, there was localized inflammatory reaction. But, pulp revasculization and healing had already begun in the root area. At 5 days after replantation, odontoblast-like cells were observed. Tertiary dentin deposition was observed beneath the pulp-dentin border from 1 week after replantation. And tertiary dentin was increased at 2 weeks after replantation. The presence of odontoblast-like cells and the formation of tertiary dentin were continued to 4 weeks after replantation. At 4 weeks after replantation, the deposition of bone-like tissues and cementum-like tissues was observed. This results show that there is a possibility of pulp healing after tooth replantation in rats and the mineralization of tooth can progress. The mineralization of tooth after replantation was initially occurred by the deposition of tertiary dentin, but as time passed, the deposition of bone-like tissues and cementum-like tissues was begun and increased.
Animals ; Dental Pulp ; Dentin ; Molar ; Rats ; Replantation ; Tooth ; Tooth Replantation

Background: Thrombocytopenia is a condition where platelet counts are below the normal range (< 150 ×103 /µL), resulting in a higher risk of bleeding and affecting the results of hip arthroplasty. We assessed the impact of preoperative platelet counts on the clinical results of patients who underwent hip arthroplasty. Methods: Between April 2003 and March 2023, 437 patients (451 hips), who had preoperative thrombocytopenia of less than 150 ×103 /µL platelets, underwent hip arthroplasty. Preoperative platelet levels were categorized into severe thrombocytopenia (< 50 ×103 /µL) and non-severe thrombocytopenia (50–149 ×103 /µL). Total blood loss, operation time, requirement of transfusion, amount of transfusion, duration of surgical wound oozing, length of hospital stay, mortality rate at 1 year after surgery, and any complication were compared between the 2 groups. Results: No notable differences were observed in the surgery time or the total amount of blood loss between the groups. The requirement of transfusion and the amount of transfused blood were higher in the severe thrombocytopenia group. Prolonged oozing was found in around 18% in both groups, while periprosthetic joint infections occurred in 3 of the non-severe thrombocytopenia group. No significant difference was noted in the duration of hospital stay (25.6 ± 18.3 days vs. 19.4 ± 16.6 days, p = 0.067) and 1-year mortality (22.2% vs. 11.8%, p = 0.110). Conclusions Hip arthroplasties are safe for patients with low platelet counts and do not lead to prolonged hospital stays. On the other hand, patients with severe thrombocytopenia tend to need blood transfusions more frequently than those with less severe thrombocytopenia.

Recent evidence has strongly suggested that the CAP/TC10 pathway is involved in the trafficking, docking,and fusion of vesicles containing the insulin- responsive glucose transporter Glut4 to the plasma membrane. However, little is known about how the genes employed in the CAP/TC10 pathway are associated with the development of type 2 diabetes mellitus. In this study, we sequenced 4 genes of the CAP/TC10 pathway [SORBS1, CBL, CRK, and RHOQ] in 24 individuals to identify genetic variations in these loci. A total of 48 sequence variants were identified, including 23 novel variations. To investigate the possible association with type 2 diabetes mellitus, 3 single nucleotide polymorphisms from SORBS1, 3 from CBL , and 4 from RHOQ were genotyped in 1122 Korean type 2 diabetic patients and 1138 nondiabetic controls. Using logistic regression analysis, 1 significant association between SNP rs1376405 in RHOQ and type 2 diabetes mellitus [OR = 8.714 (C.I. 1.714-44.29), p = 0.009] was found in the recessive model. Our data demonstrate a positive association of the RHOQ gene in the CAP/TC10 pathway with T2DM in the Korean population.
Cell Membrane ; Diabetes Mellitus, Type 2 ; Genetic Variation ; Glucose Transport Proteins, Facilitative ; Humans ; Insulin ; Logistic Models ; Polymorphism, Single Nucleotide ; Signal Transduction

PURPOSE:Temporal lobe epilepsy(TLE) is now recognized as a distinct syndrome in adults. The seizure evolution in adult patients is well characterized, manifesting initially with an aura, behavioral arrest, automatism, and secondary generalized tonic-clonic seizures. In contrast, relatively few studies are available for the pediatric age group. In the present study, we investigated children undergoing temporal lobectomy for refractory seizures and correlated the pathologic findings with clinical presentations. METHODS:The records of the pediatric patients admitted at the Seoul National Children's Hospital for epilepsy surgery between January 1995 and December 2005 were reviewed. Then, eighteen patients were included in this study. The clinical records were reviewed in terms of the patient profiles imaging findings, surgical techniques, and pathologic findings. The seizure outcomes were described according to the Engel's classification. RESULTS:The postsurgical outcomes were favorable. Lateral temporal epilepsy was more common in childhood than in adulthood. Dual pathology was commonly found. Arm dystonia or tonic arm elevation have a lateralizing value. Head turning may have a lateralizing value based upon a time sequence. The brain MRI was less predictable for pathologic findings. The ictal EEG cannot always have a localizing value. Delta beginning in the ictal rhythm may suggest lateral lobe epilepsy. Anterior temporal beginning of the ictal location may suggest mesial temporal lobe epilepsy. Ganglioglioma tends to cause rhythmic beta activities at the beginning of the ictal event. CONCLUSION:TLE in childhood shows more complex and atypical clinical manifestations and have more variable etiologies. No single presurgical investigation can be a good predictable value to localization or lateralization.
Adult ; Arm ; Automatism ; Brain ; Child ; Classification ; Dystonia ; Electroencephalography ; Epilepsy ; Epilepsy, Temporal Lobe* ; Ganglioglioma ; Head ; Humans ; Magnetic Resonance Imaging ; Pathology ; Seizures ; Seoul ; Temporal Lobe*

BACKGROUND: The contingent negative variation (CNV) reflects neuronal activities related to sensorimotor integration and motor planning or execution and is probably originated from the frontal-subcortical circuit. The aim of this study is to investigate the neurophysiologic changes in uremia and the effect of hemodialysis to them by utilizing the CNV test. METHODS: Fifteen right-handed healthy subjects and 12 patients with end stage renal disease (ESRD) were studied. CNV was recorded from Fz, Cz, and Pz referenced to linked ear lobes by using an S1 (click)-S2 (flashes)-key press paradigm. The amplitude of initial CNV (iCNV) was calculated as the average amplitude of 550~750 msec after S1. The amplitude of late CNV (lCNV) was calculated as the average amplitude between 200 msec before S1 and S2. The test was repeated for the patients group at the time of pre- and post-hemodialysis. Neuropsychological measurements, the trail making test (TMT) and mini-mental state score (MMSE), were conducted at the time of each test. RESULTS: Both the mean amplitudes of iCNV and lCNV at the vertex (Cz) were significantly lower in the patient group than those in the control group (p<0.05). The MMSE score and TMT were also significantly different between the patient and control group (p<0.05). There was no significant correlation between the values of neuropsychological tests and the parameters of CNV. Both iCNV and lCNV were not significantly different between the pre- and post-dialysis test. CONCLUSIONS: It appears that CNV negativity in uremia reflects dysfunctions in the frontal-subcortical circuit. In addition, hemodialysis seems to have no significant effect on it in patients with ESRD.
Contingent Negative Variation* ; Ear ; Evoked Potentials ; Humans ; Kidney Failure, Chronic* ; Neurons ; Neuropsychological Tests ; Renal Dialysis ; Trail Making Test ; Uremia

Reptiles were known to serve as paratenic hosts for Centrorhynchus (Acanthocephala: Centrorhynchidae) in Korea, but the infection course in experimental animals was not elucidated yet. In this study, the tiger keelback snakes (Rhabdophis tigrinus) were collected and digested with artificial pepsin solution, and the larvae of Centrorhynchus were recovered from them. Then, the collected larvae were orally infected to rats for developmental observations. In rats, all the larvae were observed outside the intestine on day 3 post-infection (PI), including the mesentery and abdominal muscles. As for the development in rats, the ovary of Centrorhynchus sp. was observed at day 15 PI, and the cement glands were 3 in number. Based on the morphological characteristics, including the arrangement of proboscis hooks, these larvae proved to be a species of Centrorhynchus, and more studies were needed for species identification.

Osteoporosis is characterized by impaired osteogenesis. BMD is a major determinant of bone strength. The role of the VDR gene in predisposition to primary osteoporosis has been recognized. However, population-based case-control studies have been reported controversial results for known candidate genes in an ethnically distinct group. To determine the genetic effects of VDR variants on osteoporosis and BMD, we directly sequenced the VDR gene in 24 unrelated Korean individuals and identified eighteen sequence variants. We investigated the potential involvement of eight SNPs in osteoporosis in postmenopausal women (n = 729). Two SNPs (LD) in intron 2, -5294G > C (rs2238135) and -4817G > A (rs17882443) showed the evidence of association with enhanced BMD of the femoral neck (p(additive) =0.031 for rs2238135; p(additive)=0.017 and p(dominant)= 0.019 for 17882443). Moreover, VDR -4817G > A was significantly associated with protective effect on all fracture risk (p(recessive)=0.035, OR=0.2, 95% CI=0.05~0.89), and tended to be higher BMD values at various proximal femur sites. Therefore, we suggest that the -4817G > A may be useful genetic marker for vitamin D-related metabolism and may have an important role in the increased BMD of the proximal femur in postmenopausal Korean women.
Bone Density ; Case-Control Studies ; Female ; Femur ; Femur Neck ; Genetic Markers ; Humans ; Introns ; Osteogenesis ; Osteoporosis ; Polymorphism, Single Nucleotide ; Receptors, Calcitriol ; Vitamin D ; Vitamins