Using computerized motion analysis techniques, kinematics of foot trajectories were quantitatively analyzed in twelve rats before and after dorsal spinal cord hemisection at the T6 level. Although overground locomotion in these animals returned to normal within four weeks, some kinematic variables during treadmill locomotion did not recover to pre-lesion level. Immediately following dorsal hemisection, amplitudes of both hindfeet horizontal and vertical movements were dramatically reduces. However, in three weeks, the amplitudes of horizontal movement(stride length) became significantly larger than of pre-lesion strides. On the other hand, amplitude of hindlimb vertical movement showed very little recovery. Forelimb-hindmill coordination was also disrupted initially but returned to normal within three weeks. The duration of hindlimb swing phase became significantly longer after sectioning and gradually recovered, but never to pre-lesion levels. Interestingly, amplitudes of forelimb vertical movement. which was depressed initially, became significantly largery three weeks after lesioning. A dramatic increase in the statistical variation of limb kinematics, which persisted even after motor recovery, is an important parameter for the evaluation of neural deficits in spinal cord injuries. Kinematic analysis is a sensitive technique for the detection of minor motor deficits following nerve injuries.
Animals ; Biomechanical Phenomena ; Extremities ; Foot ; Forelimb ; Hand ; Hindlimb ; Locomotion* ; Rats* ; Spinal Cord Injuries ; Spinal Cord*

Recently, motor evoked potential(MEP) using cortical surface of transcranial stimulation have been used to monitor the integrity of motor pathways and map motor cortex in human and animal. The primary concept using motor evoked potentials(MEPs) for test of motor pathways was based on the assumtion that pyramidal neurons in the motor cortex are activated by electrical stimulation applied on the cerebral cortex and synchronized compound action potentials are conducted mainly along the corticospinal tracts in the spinal cord. However, the origins and the descending pathways of these MEPs in small animals may be different from those of potentials evoked by intracortical microstimulation because of current spread. Our previous study revealed that the origns of the MEPs in rats differed from those previously believed and may be reticular nuclei. To further clarify those results and localize the intraspinal pathways conduction MEPs, consecutive vertical and/or horizontal sections of the spinal cord were performed at T9 cord level in twelve rats. MEPs were recorded at T2/3 and L2/3 before and after each section and sequential alterations of MEPs were observed. In six rats, the stimulation was alternated between the right and left cortex and the lateralities of conduction pathways were compared. All six cases showed no differences of MEPs and pattern of wave abolition after each section between right and left brain stimulation. The alteration of MEPs after each consecutive section was categorized by analyzing latency shift, amplitude change, and disappearance of waves. We divided a cross section of T9 spinal cord into forty-six squares. If one of the categorized changes occurrd after cutting an area, the appropriate score was given for the area since more change of waves meant more significant contribution of the cut area to conduction of MEPs. The score of twelev rats were summed in each forty-six spots and map showing the distribution of MEPs was constructed. The map revealed that MEPs were conducted along the wide area of ventral and lateral funiculus of the spinal cord but mainly along the medial portion of the ventral funiculus of the spinal cord but mainly along the medial portion of the ventral funiculus and ventral portion of the larteral funiculus through which reticulospinal and vestibulospinal tracts pass. No conduction of MEPs along the corticospinal tracts was confirmed. This finding supports the result of our previous study. However, this extrapyramidal MEP conducted along ventral spinal cord in addition to somatosensory evoked potential(SSEP) which is conducted along posterior funiculus can be useful to monitor the integrity of the whole spinal cord. Moreover, the extrapyramidal MEP can be more useful than pyramidal MEP in rats because the reticular formation plays a more important role in motor function and pyramidal tract is located in posterior funiculus.
Action Potentials ; Animals ; Brain ; Cerebral Cortex ; Efferent Pathways ; Electric Stimulation ; Evoked Potentials, Motor* ; Extrapyramidal Tracts ; Humans ; Motor Cortex ; Neurons ; Pyramidal Tracts ; Rats* ; Reticular Formation ; Spinal Cord

Motor evoked potential(MEP) produced by cortical surface or transcranial stimulation has evolved as a new clinical and experimental tool to monitor the integrity of motor pathways and to map motor cortex. Clinical assessment of motor system using MEP has further advanced with recent development of the magnetic stimulator. The primary concept using MEPs for test of motor pathways was based on the assumption that pyramidal neurons in the motor cortex are activated by electrical stimulation applied on the cerebral cortex and synchronized compound action potentials are conducted mainly along the corticospinal tracts in the spinal cord. However,recent studies indicated that the origins of the Meps in non primates may differ from those previously believed. In order to use MEPs as a clinical or experimental tool, it is essential to clarify the origin of MEPs. Therefore, goals of this study were : (1) to investigate the origin of MEPs, and (2) to design the most reliable but simple method to evoke and monitor MEPs. In a total of fifteen rats, MEPs were produced by cortex to cortex stimulation and were monitored using a pair of epidural electrodes. Using varying stimulus intensities, the amplitudes and latencies of MEPs were statistically analyzed. The latencies and amplitudes of the MEPs in these animals showed surprisingly large standard deviations, which were partially resulted in these animals showed surprisingly large standard deviations, which were partially resulted from convergence of neighboring waves during high stimulation intensities. Wave forms of MEPs were also varied greatly depending on the position of recording electordes. At low stimulus intensities, most consisten MEPs were obtained when the stimulating electrodes were placed on the hard palate and the temporal muscle, not on the motor cortex. This observation indicates that the primary source of MEPs is not the motor cortex in the rat. When the potentials generated by direct stimulation of motor cortex and those generated by reticular nuclei were monitored epidurally in the same preparation using the same electrodes, these potentials generated by different sources actually identical in their latencies and wave forms. However, the threshold stimulus intensities evoking these potentials were quite different in the two metholds. The threshold was much lower to evoke potentails by reticular nuclei stimulation. It suggests that MEPs are geneated by the reticular nuclei or brain structure located in the brain stem. The observation that the motor cortex play no major roles in generating MEPs was confirmed by sequential sections of neural axis from the motor cortex to brain stem in three rats. All these findings suggested that neither direct motor cortex stimulation not transcranial stimulation did evoke MEPs originating from the motor cortex in rat. These stimulating methods activate reticular nuclei by stimulus current spread to the brain stem. Since the reticular formation plays an important role in motor function in rats, MEP originated from reticular nucleus can be an important testing of the motor function in rats. Moreover, transcranial stimulation of the brain is technically easy. This technique producing MEPs originated from reticular nucleus can be useful to monitor the integrity of motor pathways.
Action Potentials ; Animals ; Axis, Cervical Vertebra ; Brain ; Brain Stem ; Cerebral Cortex ; Efferent Pathways ; Electric Stimulation ; Electrodes ; Evoked Potentials, Motor* ; Extrapyramidal Tracts ; Motor Cortex ; Neurons ; Palate, Hard ; Primates ; Pyramidal Tracts ; Rats* ; Reticular Formation ; Spinal Cord ; Temporal Muscle

Patient with skeletal class II relationship was treated with L-ARS. L-ARS is fixed functional appliance that could be effective in children and adolescent patient who don't wear activator. The following results were obtained; 1) Growth of Mandible was stimulated and overjet was decreased, therefore coupling of anterior teeth was established with L-ARS which is fixed functional appliance. 2) These changes were accomplished with Mandibular skeletal growth with no effect on the Maxilla. 3) L-ARS was especially effective on patient who deny to wear the removable functional appliance.
Adolescent ; Child ; Humans ; Malocclusion* ; Mandible ; Maxilla ; Tooth

BACKGROUND AND PURPOSE: Knowledge of a patient's cerebral vascular status is essential for accurately classifying stroke. However, vascular evaluations have been incomplete in previous studies, and a stroke registry based on the results of such vascular investigations has not been reported. The purpose of the present study was to classify ischemic strokes based on vascular imaging data. METHODS: Between May 2001 and August 2003, 1,264 patients with acute (< 7 days) ischemic stroke were admitted to Asan Medical Center. Among them, 1,167 patients (750 men and 417 women; mean age 63.3 years) underwent an angiogram (mostly a magnetic resonance angiogram) and were included in this study. Electrocardiography and computed tomography/magnetic resonance imaging were performed in all patients, while 31.2% underwent echocardiography. The subtypes were categorized with the aid of a modification of the Trial of ORG 10172 in the Acute Stroke Treatment classification. RESULTS: Large-artery atherosclerosis (LAA) was the most frequent subtype (42%), followed by small-vessel occlusion (SVO, 27%), cardiogenic embolism (CE, 15%), undetermined etiology (15%), and other determined etiology (1.5%). Risk factors included hypertension (71%), cigarette smoking (35%), diabetes mellitus (30%), history of previous stroke (22.7%), emboligenic cardiac diseases (20%), and hypercholesterolemia (11%). Hypertension was more common in patients with SVO than in those with other subtypes (p<0.05), and the case-fatality rate was higher in patients with CE than in those with other subtypes (p<0.01). The functional outcome was worse in patients with LAA than in those with other stroke subtypes (p<0.01). CONCLUSION: According to the stroke registry based on vascular imaging results, LAA was the most common stroke subtype followed by SVD. The high incidence of LAA is probably related to the increased identification of the presence of intracranial atherosclerosis by MR angiogram.
Atherosclerosis ; Chungcheongnam-do ; Classification ; Diabetes Mellitus ; Diagnosis ; Echocardiography ; Electrocardiography ; Embolism ; Female ; Heart Diseases ; Humans ; Hypercholesterolemia ; Hypertension ; Incidence ; Intracranial Arteriosclerosis ; Male ; Risk Factors ; Smoking ; Stroke*

Abnormal hematological values are associated with various disorders including cancer and cardiovascular, metabolic, infectious, and immune diseases. We report the copy number variations (CNVs) in clinically relevant hematological parameters, including hemoglobin level, red and white blood cell counts, platelet counts, and red blood cell (RBC) volume. We describe CNVs in several loci associated with these hematological parameters in 8,842 samples from Korean population-based studies. The data that we evaluated included four RBC parameters, one platelet parameter, and one associated with total white blood cell (WBC) count, exceeding the genome-wide significance. We show that CNVs in hematological parameters are associated with some loci, different from previously associated loci reported in single nucleotide polymorphism (SNP) association studies.
Blood Cell Count ; Blood Platelets ; Coat Protein Complex I ; Erythrocytes ; Genome-Wide Association Study ; Hemoglobins ; Immune System Diseases ; Leukocyte Count ; Leukocytes ; Platelet Count ; Polymorphism, Single Nucleotide

PURPOSE: The in vitro dissolution of intrahepatic stones was evaluated using the various solvent mixtures. MATERIALS AND METHODS: Sixty four intrahepatic stones from 16 patients were used. Four kinds of solvent mixtures(No. 1 = basic buffer + EDTA, No. 2=1 + Sulfobetain-12, No. 3=2 + N-acetylcysteine, No. 4=3 + urea) were used. Dissolution rates were determined by measuring the weight loss of stones after 6, 12, 24, 48 hours incubation periods, respectively. RESULTS: The highest dissolution rates in dissolving intrahepatic stones were achieved with No. 4 solvent mixture(1% W/V EDTA/80mM, Sulfobetain-12/1 M, urea, pH 9.5). CONCLUSION: lntrahepatic stones could be largely dissolved up to about 70% of their initial weight after 48 hours incubation period in vitro.
Acetylcysteine ; Edetic Acid ; Humans ; Hydrogen-Ion Concentration ; Urea ; Weight Loss

Objective: Recently data has been accumulated regarding the role of coping strategies in the relationship between stress and sleep quality. Therefore, we set out to identify the mediating effects of coping strategies between stress and sleep quality. Methods: A online-based cross-sectional study was performed using the Perceived Stress Scale-10, the Pittsburgh Sleep Quality Index, and a simplification of the 60-item Coping Orientation to Problems Experienced (Brief COPE) inventory in the nonclinical adult sample. The 24 items of Brief COPE were categorized into four factors (social support, problem solving, avoidance, positive thinking). Then, we used the PROCESS macro to conduct the multiple mediation analysis for the four coping styles as potential mediators in the relationship between stress and sleep quality, and an additional subgroup analysis was examined to identify a gender difference for the mediation effect. Results: As a group, four coping styles mediated significantly the association between perceived stress and poor sleep quality. And avoidance has maintained its significance thought all regression analyses. Finally, this results remained as same in the females. Conclusion The effect of perceived stress on poor sleep quality was mediated by coping strategies, especially by avoidance. Thus, further research should consider the coping styles of individuals to reduce the influence of stress on sleep quality.

PURPOSE: To determine the accuracy of three-dimensional CT angiography(CTA) in the diagnosis of intracranialaneurysms. MATERIALS AND METHODS: 3D-CTA was performed in 46 consecutive patients with subarachnoid hemorrhage orsuspected intracranial aneurysm. Images were obtained using a helical CT scanner and the SSD techinque. 3D CTAfindings were reviewed retrospectively and independently in blind fashion by two neuroradiologists. Digitalsubtraction angiography(DSA) was used as the reference standard. RESULTS: DSA revealed, in 36 patients, 40aneurysms ranging from 2mm to 12mm in maximal diameter, and negative findings in 10 patients. For observer 1, theaccuracy of 3D-CTA for all aneurysms and all patients was 85.2% and 82.7%, respectively. For observer 2, therespective figures were 94.6% and 91.9%. The agreement rates between the two observers were 86% for all aneurysmsand 87% for all patients (Kappa value 0.58, 0.59). CONCLUSION: Three-dimensional CTA is a useful imagingtechnique for the diagnosis of intracranial aneurysms, with an accuracy of over 85%
Aneurysm ; Angiography* ; Diagnosis ; Humans ; Intracranial Aneurysm* ; Retrospective Studies ; Silver Sulfadiazine ; Subarachnoid Hemorrhage ; Tomography, Spiral Computed

BACKGROUND/AIMS: We aimed to verify the prognostic factors of stage II rectal cancer and the effect of radiation therapy on the survival and local recurrence rate. METHODS: This study was undertaken in 202 patients who underwent curative resection of rectal cancer and confirmed to be stage II between July 1989 and December 1996. Univariate and multivariate (Cox's model) analyses of survival were employed to identify prognostic factors. Statistical significance was assigned by p value of <0.05. RESULTS: Overall recurrence occurred in 32 patients. Four patterns of recurrence were observed: hematogenous recurrence in 17 patients, local recurrence in 11, peritoneal seeding in two and simultaneous hematogenous and local recurrence in two cases. Overall 5-year survival rate was 85.6% and 5 year disease free survival rate was 82.8%. There was no significant difference in local recurrence rate and survival according to radiation therapy or location of cancer. In multivariate analysis, the number of harvested lymph node was only a prognostic factor. CONCLUSIONS: The number of harvested lymph nodes has prognostic value in stage II rectal cancer. Postoperative radiation therapy should be considered for stage II rectal cancer with poor prognostic factors although radiation did not decrease local recurrence rate in present study.
Adolescent ; Adult ; Aged ; Child ; English Abstract ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Metastasis ; Neoplasm Recurrence, Local ; Prognosis ; Rectal Neoplasms/pathology/*surgery