Mouse Dual Ig Domain Containing Cell Adhesion Molecule Protein Expression and Purification Using the Baculovirus Expression Vector System

A baculovirus expression vector system (BEVS) is used routinely to produce recombinant proteins in the milligram scale. Dual Ig domain containing cell adhesion molecule (DICAM) belongs to the type I class of transmembrane proteins. It consists of a signal peptide, two V-type Ig domains in the extracellular region, and a short cytoplasmic tail of 442 amino acids. To purify the recombinant DICAM protein from cells overexpressing the mouse full-length DICAM gene, recombinant baculovirus is infected and recovered in the Sf9 cells. As a result, mouse DICAM protein was efficiently expressed and extracted from the insect cells using the BEVS. This recombinant protein can be used in further studies for functional test of DICAM protein in the cells.

EDTA-dependent Pseudothrombocytopenia Confirmed by Supplementation of Kanamycin: A Case Report

EDTA-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a spurious low platelet count due to EDTA-induced aggregation of platelets. Since the failure to recognize EDTA-dependent PTCP may result in incorrect diagnosis and inappropriate treatment, the recognition of this phenomenon is very important. We report an insidious case of EDTA-dependent PTCP confirmed by supplementation of kanamycin to anticoagulant in a 53-year-old women. Although sodium citrate and heparin usually prevented the aggregation of platelets in EDTA-dependent PTCP patients, these anticoagulants failed in preventing PTCP in our case. EDTA-dependent PTCP was confirmed by the findings that the clumping of platelets on microscopic evaluation was found in EDTA-anticoagulated blood samples, whereas thrombocytopenia and platelet aggregation were not revealed in the sample supplemented with kanamycin.

Symptomatic Eosinophilic Peritonitis in CAPD Treated with Low Dose of Oral Prednisolone / 대한신장학회잡지

Eosinophilic peritonitis is not uncommonly observed in patients on peritoneal dialysis. It typically occurs within the first 3 months after the initiation of peritoneal dialysis. Eosinophilic peritonitis is usually a benign and self-limiting process with the exception of fungal eosinophilic peritonitis. The use of oral or intraperitoneal steroids has been suggested only for patients with abdominal pain or with markedly turbid peritoneal effluent. We report a case of eosinophilic peritonitis with severe abdominal pain, which successfully resolved on treatment with single dose of oral prednisolone.

Properties of GST-CALM expressed in E. coli

Clathrin-coated vesicles (CCVs) are involved in protein and lipid trafficking between intracellular compartments in eukaryotic cells. CCVs are composed of clathrin and assembly proteins. The clathrin assembly protein lymphoid myeloid leukemia (CALM) gene, encodes a homologoue of the neuronal clathrin assembly protein AP180. In this study, we characterized the properties of the CALM expressed in E. coli. The molecular weight of bacterially expressed GST-CALM fusion protein was approximately 105 kD on SDS-PAGE. The CALM protein could promote clathrin triskelia into clathrin cages and could bind the preformed clathrin cage. However, 33 kD N-terminal domain of CALM could not bind pre-assembled clathrin cages, but assemble clathrin triskelia into clathrin cages. The CALM protein was bound to SH3 domain through N-terminal domain1, in vitro. The CALM protein is proteolyzed by caspase 3, caspase 8 and calpain through C-terminal domain.

A comparison between obstructive hydrocephalus and non-obstructive hydrocephalus on midsagittal brain MRI

Hydrocephalus refers to distension of the cerebral ventricles, usually as the result of obstruction somewhere along the pathway of the cerebrospinal fluid circulation. Hydrocephalus ex vacuo means ventricular enlargement in the presence of cerebral atrophy or irreversible loss of brain parenchyma. According to morphologic change of ventricular enlargement, the mechanism and results of treatment are quite different. MRI improves diagnostic accuracy in patients with hydrocephalus because of its ability to show small obstructing lesion and anatomical changes. To evaluate differential points, we compared patients with obstructive hydrocephalus and non-obstructive hydrocephalus. T1-weighted sagittal images were retrospectively analyzed in 19 patients with obstructive hydrocephalus, 22 non-obstructive hydrocephalus, and 36 normal subjects. On midsagittal section, we evaluated mamillopontine distance, thickness and shape and position of the corpus callosum, and antero-inferior portion of the 3rd ventricle. The average mamillopontine distance was 11.5mm for normal subjects, 8.2mm for obstructive hydrocephalus group, and 13.6mm for non-obstructive hydrocephalus group(p < 0.01). Dilatation of the anterior inferior portion of the 3rd ventricle was seen only in 11 patients of obstructive hydrocephalus group. Average thickness of the corpus callosum at the level of the foramen of Monro was 7.5mm for normal subjects, 5.1mm for obstructive hydrocephalus group, and 4.4mm for non-obstructive hydrocephalus group(p < 0.01). There was a difference in the shape of corpus callosum between obstructive hydrocephalus and non-obstructive hydrocephalus group. It is concluded that mamillopontine distance, thickness and shape of the corpus callosum, dilatation of the antero-inferior 3rd ventricle could be good differential points between obstructive hydrocephalus and non-obstructive hydrocephalus.

Three Cases of Chronic Cerebral Paragonimiasis

Although CNS involvement of paragonimiasis is not frequently encountered, it has been reported in 10-25% of clinical cases of all paragonimiasis. It causes various symptoms and signs including epilepsy, headache, hemiparesis, visual field defect or other neurologic deficits. Infestation usually occurs by ingestion of freshwater crabs or crayfish infected with Paragonimus metacercariae. We report three patients with chronic cerebral paragonimiasis, which were diagnosed by history, neurologic examination, radiological and serological evaluations, Two of them had history of ingestion of freshwater crabs or crayfish in childhood. Only one patient showed a positive enzyme-linked immunosorbent assay reaction for Paragonimus specific antibody in serum and CSF. Their clinical manifestations were seizure, headache, and visual field defect. In their plain skull X-rays, congregated round oval calcifications were recognized. Brain computed tomography of patients revealed pathognomonic findings of multiple, variable sized, round, calcified lesions surrounded by low density areas together with cortical atrophy in occipital, parietal, and temporal lobes.

Abnormalties of Ocular Motor Movement in Patients with Parkinson's Disease

OBJECTIVE : We investigated the relationship between the severity of the disease and the abnormality of some ocular movements in parkinson's disease. BACKGROUND: Disorders of eye movements have been described in diseases of the basal ganglia for over a century and ocular motor deficits of the saccadic and pursuit system have been reported in parkinsonian patients. METHOD : We studied the electro-oculography of the eye tracking and saccadic movement in 26 patients (11 males, 15 females) with Parkinson's disease. The severity of the disease was divided into two groups by Hoehn & Yahr(H-Y) staging, H-Y stage 1, 2(group A) and H-Y stage 3, 4 (Group B). Some patients antiparkinsonian drugs of L-dopa, dopamine agonist and anticholinergics. RESULT : The velocity of smooth pursuit and the velocity and latency of saccade were calculated and compared between two groups. Eye tracking test revealed decreased pursuit velocity leading to catch-up saccades, but normal phase relationship between eye and target movement, while saccadic eye movement had increased latency. These results showed more profound severity in more advanced stages of the disease. CONCLUSION : We suggest that ocular movement be often chosen as a simple but relevant example of general motor function, as well as criteria for staging of Parkinson's disease and basal ganglia play significant role in ocular movement.

Two Cases of Thoracic Myelopathy Secondary to Ossification of the Ligamentum Flavum

Hypertrophied ligamentum flavum is not a common cause of myelopathy. Only a minority of cases in the previous reports of myelopathy or radiculopathy secondary to thickening of the ligamentum f lavum had calcification of the ligamentum. We report two cases of thoracic myelopathy caused by ossified ligamentum flavum. One case was a twenty-five year old female who complained of weakness of lower limbs. The other was a fifty-three year old male who complained of tingling sensation on both lower extremities and weakness of right leg. These two patients showed weakness of lower extremities associated with hypesthesia below the level of calcified ligamentum flavum, positive ankle clonus, extensor plantar response, and hyperreflexia. Magnetic resonance imaging (MRI) showed clearly the spinal cord compression at the second to fourth thoracic level by a low-intensity-signal lesion. Metrizamide myelography with computerized tomography showed precise preoperative diagnosis and anatomic localization of the lesion. About one month after laminectomy and removal of the ossified ligaments flava, there was improvement of weakness, hypesthesia and ankle clonus.

Cyanide-induced Parkinsonism

Since cyanide poisoning is almost always fatal, reports of surviving patients to develop neurologic signs are rare. Systemic hypoxemia was not documented with arterial blood gases : however, significant tissue hypoxia most likely occurred from the action of cyanide. A38-year-old man ingested cyanide in a suicidal attempt. He was treated and survived the poisoning episode. But one week later, he showed classic extrapyramidal symptoms and signs, characterized by pit disturbance, bradykinesia, increased muscle tone, micrographia, tremor, apraxia of eyelid opening, palilalia. These symptoms and signs continued to progress, and response to levo-dopa and anticholinergics was poor, except apraxia of eyelid opening. About 3 months later, brain MRI showed abnormal signals (increas ed signal intensity on T2WI, decreased signal intensity on TIWI) in both globus pallidus and a part of putamen, but hippocompus and substantia nigra was normal. After 16 months, follow-up brain MRI showed the same findings. Although brainstem auditory evoked potential(BAEP) was normal, motor evoked potential(MEP) showed prolongation of central motor conduction time(CMCT) in right upper and lower extremities, then wecould suspect subtle changes in pyramidal tract. We report a patient as cyanide-induced parkinsonism by history, neuroimaging finding, and clinical parkinsonian symptoms and signs.