Neuropsychological correlates of error negativity and positivity in schizophrenia patients

The purpose of the present paper was to determine error-monitoring ability and its relationship with executive function in patients with schizophrenia. In order to evaluate error-monitoring ability, the error negativity (Ne) and error positivity (Pe) were measured using the Stroop task. The correct-related negativity (CRN) and positivity (Pc) were also measured. In addition, neuropsychological tests were administered in order to evaluate executive function. The patients with schizophrenia had significantly reduced Ne and augmented CRN amplitudes, but the Pe and Pc amplitudes of the patients were comparable to those of the controls. In addition, the Ne amplitude, measured at Fcz was positively correlated with the Trail Making Test (TMT), part B response time, and the categories achieved on the Wisconsin Card Sorting Test (WCST) in patients with schizophrenia. No significant correlations were found between Ne amplitude and performance on the neuropsychological tests in the controls. And no associations were detected between CRN, Pe, Pc amplitudes and neuropsychological performance, in either the patients with schizophrenia or the controls. Reduced Ne amplitudes and augmented CRN amplitudes in patients with schizophrenia suggest the dysfunctional behavior-monitoring system in these patients. The functional significances of Ne and Pe are discussed.     

Application of the Ilizarov Technique to the Correction of Neurologic Equinocavovarus Foot Deformity

Background  

The treatment of rigid equinocavovarus foot deformities caused by neurologic disorders is often difficult and relapse is common.     

Colorectal mucinous carcinoma: findings on MRI

PURPOSE: The purpose of this work was to define the characteristic MR features of colorectal mucinous carcinomas and to correlate the mucin pool with the signal intensity of this tumor. METHOD: MRI of 12 cases of pathologically proven colorectal carcinoma containing mucin was evaluated. We analyzed the signal intensity of tumor on T1- and T2-weighted MR images and correlated the area of intratumoral high signal intensity on T2-weighted images with the mucinous pool on the pathologic specimens. Two radiologists independently estimated the area of high signal intensity in the tumor on T2-weighted images and one pathologist estimated the amount of mucinous pool in the pathologic specimen. RESULTS: In 9 (75%) of 12 cases, focal or diffuse high signal intensity areas were detected on T2-weighted fast spin echo images. In seven cases in which mucin pools were seen macroscopically, partial (n = 3) or diffuse high signal intensity areas were noted on the T2-weighted images. Among the five cases in which microscopic mucinous pools were detected on the pathologic slides, three cases showed no high signal foci on MR images, and in the remaining two cases, high signal intensity areas were noted as small foci. CONCLUSION: Intratumoral high signal intensity on T2-weighted fast spin echo MR images occurs in mucinous carcinomas and correlates with the mucin pools on pathologic specimens.     

Tumor Necrosis Rate Adjusted by Tumor Volume Change Is a Better Predictor of Survival of Localized Osteosarcoma Patients

Background We assessed whether new parameter that considers both tumor volume change and necrosis rate predicts metastasis-free survival of localized osteosarcoma patients. We also evaluated relationship between tumor volume change and necrosis rate or metastasis-free survival. Methods We retrospectively reviewed 151 patients with stage II osteosarcoma who were treated with surgery and neoadjuvant chemotherapy. The tumor volume change was measured and calculated based on pre- and postchemotherapy magnetic resonance images. The mean metastasis-free interval was 83.1 months. We calculated adjusted tumor necrosis rate as following formula: 100–(100–necrosis rate) × postchemotherapy/prechemotherapy tumor volume. Survival and logistic regression analyses were used to evaluate the correlation among size parameters, tumor necrosis rate and survival. Results The 5-year metastasis-free survival rate of 151 patients was 71.4% (95% CI, 67.7–75.1%). American Joint Committee on Cancer (AJCC) stage IIB (RR 2.27; 95% CI, 1.11–4.62; P = 0.025) and poor adjusted tumor necrosis rate (RR 2.02; 95% CI, 1.05–3.89; P = 0.035) independently correlated with metastasis-free survival period. Further, tumor volume change independently correlated with necrosis rate. Decreased tumor volume could predict good response, with sensitivity of 80.2%, specificity of 68.6%, and positive predictive value (PPV) of 74.7%. Increased or stable tumor volume could predict poor response, with sensitivity of 68.6%, specificity of 80.2%, and PPV of 75.0 %. Conclusion The necrosis rate adjusted by the tumor volume change is an independent prognostic factor in osteosarcoma. This adjusted tumor necrosis rate may serve as a basis for risk-adapted therapy in combination with other prognostic factors.     

The determination of sensation-dependent bladder emptying time in patients with complete spinal cord injury above T11

STUDY DESIGN: Retrospective investigation using urodynamic studies and medical records. OBJECTIVE: To evaluate the safety of sensation-dependent bladder emptying in complete spinal cord injury (SCI) patients, based on the preservation of the desire to void. SETTING: Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS: This study was performed retrospectively on 79 complete SCI patients with lesions above T11, who had preserved the desire to void during conventional urodynamic studies. Patients were classified according to detrusor compliance and maximal bladder capacity. The clinical and urodynamic characteristics of each group were analyzed. RESULTS: Forty-five (57.0%) patients were classified as group A and 34 (43.0%) patients were classified as group B. There were no significant differences in clinical features, such as voiding methods and the presence of autonomic dysreflexia between the two groups. Compared with group B, there were significantly more areflexic neurogenic bladder cases in group A (P<0.05). There were significantly higher maximal detrusor pressures in group B (P<0.05). There were significantly more cases with the preservation of the strong desire to void in group B (P<0.05). CONCLUSION: Not all patients with discomplete SCIs accepted the use of sensation-dependent bladder emptying. The safe use of sensation-dependent bladder emptying will be determined based on the results of urodynamic studies.     

Hemodynamic and catecholamine responses to laryngoscopy and tracheal intubation in patients with complete spinal cord injuries

BACKGROUND: Endotracheal intubation in patients undergoing general anesthesia often causes hypertension and tachycardia, which may be altered when the efferent sympathetic fiber to the cardiovascular system is interrupted. The aim of the current study was to investigate the effects of different levels of spinal cord injury on the cardiovascular responses to intubation. METHODS: Fifty-four patients with traumatic complete cord injuries requiring tracheal intubation were grouped into quadriplegics (above C7; n = 22), high paraplegics (T1-T4, n = 8), and low paraplegics (below T5, n = 24) according to the level of injury. Twenty patients without spinal injury served as controls. Arterial pressure, heart rate, and rhythm were recorded at intervals for up to 5 min after intubation. Plasma concentrations of catecholamines were also measured. RESULTS: The intubation increased the systolic blood pressure similarly in control, high-paraplegic, and low-paraplegic groups (P < 0.05), whereas it did not alter the blood pressure in the quadriplegic group. Heart rate was significantly increased in all groups; however, the magnitude was more pronounced in the high-paraplegic group (67%) than in the control (38%) and quadriplegic (33%) groups. Plasma concentrations of norepinephrine were significantly increased after intubation in all groups; however, values were lower in the quadriplegic group and higher in the low-paraplegic group compared with those in the control group. Incidence of arrhythmias did not differ among groups. CONCLUSIONS: The cardiovascular and plasma catecholamine changes associated with endotracheal intubation may differ according to the affected level in patients with complete spinal cord injuries.     

Assessment of cervical ligamentous injury in trauma patients using MRI

During a 7-year period, a consecutive retrospective series of 89 trauma patients at a Level One trauma center who had negative standard radiographs with suspected occult cervical injury were administered a cervical magnetic resonance imaging (MRI) scan. The MRI studies were fully able to assess the ligamentous status of the cervical spine in all patients and were the final step in determining the treatment of the spine. Of the total 89 patients, 82 had no ligamentous injury, and 7 had ligamentous injury. Two patients underwent surgery because of the findings on the MRI study. MRI studies of patients with negative standard radiographs but with suspected occult cervical injury are excellent and safe studies for the evaluation of cervical spinal stability because of their ability to detect ligamentous injuries that are not evident on plain radiographs.     

Dynamic sagittal imbalance of the spine in degenerative flat back: significance of pelvic tilt in surgical treatment

STUDY DESIGN: A retrospective study of 26 patients with degenerative flat back treated with corrective osteotomy. OBJECTIVE: To analyze dynamic sagittal imbalance and to elucidate the cause of postoperative persistent stooping in degenerative flat back. SUMMARY OF BACKGROUND DATA: Sagittal spinal imbalance in degenerative flat back was more evident on walking, suggesting its dynamic nature. The most puzzling complication in its surgical treatment was postoperative persistent stooping. METHODS: This study analyzed 26 surgically treated patients with preoperative gait analysis. Patients were divided into two groups according to postoperative improvement in stooping: Group 1 with marked improvement in stooping and Group 2 with persistent stooping. Various radiographic and gait parameters were compared between the two groups. RESULTS: Comparison of radiographic parameters, representing the static status of the spine, did not indicate any clue to the mechanism for persistent stooping. However, comparison of gait parameters, representing the dynamic status of the spine, revealed meaningful differences between the two groups. Among various gait parameters compared, pelvic tilt seemed to be the most important clue. Patients in Group 1 showed posterior pelvic tilt, whereas those in Group 2 showed marked anterior pelvic tilt. CONCLUSION: Degenerative flat back could be classified into two types based on pelvic position during walking: one with posterior pelvic tilt and the other with marked anterior pelvic tilt. In the former type, corrective surgery improved the stooping. In the latter, corrective surgery was ineffective, resulting in postoperative persistent stooping.     

Quantification of proteinuria in children using the urinary protein-osmolality ratio

A prospective study was conducted to determine the correlation of early morning urinary protein/osmolality ratio (mg/l/mosmol/kg) with 24-h urinary protein excretion (mg/m²/day). Study patients consisted of 53 children (aged 1 month to 15 years). Early morning urine samples and 24-h urine samples were collected and analyzed. In group 1 (children without proteinuria), early morning urinary protein/creatinine ratio (Uprot/Ucr, mg/mg) was 0.061±0.011 and the protein/osmolality ratio (Uprot/Uosm, mg/l/mosmol/kg) was 0.073±0.014. Twenty-four hour urinary protein excretion in group 1 had no significant correlation with Uprot/Ucr or Uprot/Uosm. In group II (children with proteinuria), Uprot/Ucr was 5.78±1.10 and Uprot/Uosm was 4.42±1.34. Twenty- four hour urinary protein excretion in group 2 was 1483.6±303.7 mg/m²/day and its correlation with both Uprot/Uosm and Uprot/Ucr was highly significant (r= 0.87, P<0.001 and r=0.88, P<0.001, respectively). The accepted nephrotic level of proteinuria of 40 mg/m²/h coincides with a Uprot/Uosm ratio of 1.9. In conclusion, early morning urinary Uprot/Uosm is a simple and potentially useful test for 24-h urinary protein excretion, and possibly could be used safely for the assessment of the degree of proteinuria in children. Received: 13 April 1999 / Revised: 23 February 2000 / Accepted: 15 August 2000     

The cytotoxic effect of methotrexate loaded bone cement on osteosarcoma cell lines

We mixed various amounts of methotrexate with bone cement and measured the absorbance daily for 4 weeks. The cytotoxic effects on SaOS2 and MG63 osteosarcoma cells were examined by the MTT assay, and analysed according to the methotrexate concentration and the elapsed time. The amount of eluted methotrexate was greatest during the first day, and then decreased rapidly reaching a plateau in the third week. The number of viable tumour cells decreased significantly after 72 h, and they were hardly seen after 1 week.