Biomedical subjects

Ching H Wang

Publications and source records attributed to Ching H Wang.

3 recordsLinked to original sources

PubMed2005

Hydroxyurea enhances SMN2 gene expression in spinal muscular atrophy cells.

Spinal muscular atrophy (SMA) is a motor neuron disease caused by dysfunction of the survival motor neuron (SMN) gene. Human SMN gene is present in duplicated copies: SMN1 and SMN2. More than 95% of patients with SMA lack a functional SMN1 but retain at least one copy of SMN2. Unlike SMN1, SMN2 is primarily transcribed into truncated messenger RNA and produces low levels of SMN protein. We tested a therapeutic strategy by treating cultured lymphocytes from patients with SMA with hydroxyurea to modify SMN2 gene expression and to increase the production of SMN protein. Twenty lymphoblastoid cell lines (15 SMA and 5 control lines) were treated with hydroxyurea at 5 concentrations (0.5, 5, 50, 500, and 5,000 microg/ml) and 3 time points (24, 48, and 72 hours). SMN2 gene copy numbers were determined using real-time quantitative polymerase chain reaction. Hydroxyurea treatment resulted in a time-related and dose-dependent increase in the ratio of full-length to truncated SMN messenger RNA. SMN protein levels and intranuclear gems also were significantly increased in these hydroxyurea-treated cells. The SMN2 gene copy number correlated inversely with the SMA phenotypic severity. This study provides the first evidence for a therapeutic indication of hydroxyurea in SMA.

Blotting, Western↗

PubMed2003

Industrial wastewater treatment in a new gas-induced ozone reactor.

The present work was to investigate industrial wastewater treatment by ozonation in a new gas-induced reactor in conjunction with chemical coagulation pretreatment. The reactor was specifically designed in a fashion that gas induction was created on the liquid surface by the high-speed action of an impeller turbine inside a draft tube to maximize the ozone gas utilization. A new design feature of the present reactor system was a fixed granular activated carbon (GAC) bed packed in a circular compartment between the reactor wall and the shaft tube. The fixed GAC bed provided additional adsorption and catalytic degradation of organic pollutants. Combination of the fixed GAC bed and ozonation results in enhanced oxidation of organic pollutants. In addition to enhanced pollutant oxidation, ozonation was found to provide in situ GAC regeneration that was considered crucial in the present reaction system. Kinetic investigations were also made using a proposed complex kinetic model to elucidate the possible oxidation reaction mechanisms of the present gas-induced ozonation system. As a complementary measure, chemical coagulation pretreatment was found able to achieve up to 50% COD and 85% ADMI removal. Experimental tests were conducted to identify its optimum operating conditions.

Adsorption↗

PubMed2002

Multiple ring-enhancing lesions in a child with relapsing multiple sclerosis.

The presence of ring-enhancing lesions in brain magnetic resonance images (MRIs) often raises the concern of an infectious etiology, although this radiographic finding is also seen in patients with multiple sclerosis. Multiple ring-enhancing lesions have been reported in adult patients diagnosed with multiple sclerosis but have not yet been reported in childhood multiple sclerosis. We report here a 14-year-old girl with recurrent neurologic symptoms. Her initial brain MRI showed multiple ring-enhancing lesions involving numerous white-matter fiber tracts. An extensive investigation for infectious etiologies was unrevealing. Studies of cerebrospinal fluid showed an elevated myelin basic protein and the presence of an oligoclonal band not seen in the serum. The results of electrophysiologic studies suggested a demyelinating process. The patient responded rapidly to high-dose corticosteroid treatment. However, she suffered a clinical relapse 3 months later, presenting with dysesthesia and weakness of the right arm. Repeat MRI showed multiple new active lesions. This case report illustrates that multiple ring-enhancing lesions in the brain MRI can be seen in children with multiple sclerosis and that multiple sclerosis should be considered as part of the differential diagnosis when encountering a pediatric patient with similar radiographic findings.

Adolescent↗