[Relationship between core gene mutations of hepatitis B virus and response to alpha interferon therapy in chronic hepatitis B].

Background/aims: Treatment of chronic hepatitis B with interferon results in a sustained loss of hepatitis B virus DNA and hepatitis B e antigen (HBeAg) and remission of liver disease only in a proportion of cases. Recently, mutations of hepatitis B virus (HBV) core gene have been reported as being related to the failure of interferon treatment in chronic hepatitis B. This study investigated whether core gene mutations of HBV are related to non-response to interferon therapy and whether the recurrence of HBeAg and HBV DNA in initial responders to interferon therapy is associated with the emergence of HBV core gene mutants.

[The prevalence and clinical significance of precore and core promoter mutations in Korean patients with chronic hepatitis B virus infection].

Background/aims: Precore and core promoter mutations of hepatitis B virus (HBV) have been reported in Korea but their prevalence and clinical significance have not been determined. The aims of this study were to determine the prevalence of precore and core promoter mutations and their relationships to hepatitis B e antigen (HBeAg) status, viral replication level, and severity of liver disease in Korea.

Methods: Among the patients who visited the Liver Diseases Clinics (Chung Ang University Hospital) between December 1998 and August 1999, 150 patients were randomly selected: 50 HBeAg-positive HBV-DNA positive patients by a branched DNA (bDNA) assay, 50 HBeAg-negative bDNA-positive patients, and 50 HBeAg-negative bDNA-negative patients.

Precore and core promoter mutations of hepatitis B virus and hepatitis B e antigen-negative chronic hepatitis B in Korea.

Background/aims: The aims of this study were to determine the frequency of precore/core promoter mutations and hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (e-CHB) in Korea.

Methods: Patients with chronic hepatitis B virus (HBV) infection were tested for HBeAg, anti-HBe, liver profile and HBV-DNA by a branched DNA (bDNA) assay. Serum HBV-DNA was amplified by a polymerase chain reaction and the precore/core promoter sequence was determined.

c-Myc exerts a protective function through ornithine decarboxylase against cellular insults.

c-Myc is known to control cell proliferation and apoptosis, and much effort has been focused on elucidating the mechanisms by which c-Myc works. In this study, we show that c-Myc expression is induced by many cellular insults, including cisplatin, doxorubicin, paclitaxel, 5-flourouracil, H(2)O(2), and radiation, and the enhanced expression of c-Myc protects against cell death caused by these cellular insults through ornithine decarboxylase (ODC) induction. To investigate the cellular protective role of c-Myc, we constructed a stable transfectant of ODC, one of the many transcriptional targets of c-Myc in cells, and found that enhanced expression of ODC inhibited cell death induced by cellular insults such as cisplatin, H(2)O(2,) and radiation.

Impact of burn size and initial serum albumin level on acute renal failure occurring in major burn.

Background: Acute renal failure (ARF) is not a rare occurrence in severe burns and is an important complication leading to an increase in mortality. The severity of the burn is largely determined by the burn size, and severe burns are likely to cause enough loss of extracellular fluid and albumin from plasma volume to produce shock and hypoalbuminemia.

Hypothesis: We hypothesized that initial serum albumin level may be useful as an indicator of prognosis and severity of injury in burned patients.

Protective effect of adrenomedullin in mannitol-induced apoptosis.

Mannitol therapy is widely used for reducing brain edema, and ischemic brain swelling. However, mannitol at clinical concentrations induces apoptosis in endothelial cells. Because apoptosis may be a pathogenic mechanism in vascular injury, antiapoptotic agents may have a protective role in mannitol-induced apoptosis.

Clear-cell meningioma: CT and MR imaging findings in two cases involving the spinal canal and cerebellopontine angle.

Clear-cell meningioma is a rare subtype of meningioma which occurs at a younger age and has a higher recurrence rate than other subtypes. We report two cases of clear-cell meningioma, one in the thoracolumbar spinal canal and the other in the cerebellopontine angle. Though the CT and MR imaging findings were not different from those of ordinary meningioma, after surgical removal the condition recurred repeatedly in the patient with spinal canal involvement.

In-vivo proton magnetic resonance spectroscopy in adnexal lesions.

Objective: To explore the in-vivo 1H- MR spectral features of adnexal lesions and to characterize the spectral patterns of various pathologic entities.

Materials And Methods: Thirty-one patients with surgically and histopathologically confirmed adnexal lesions underwent short echo-time STEAM (stimulated echo acquisition method) 1H- MR spectroscopy, and the results obtained were analysed.

Results: The methylene present in fatty acid chains gave rise to a lipid peak of 1.

Air-trapping zone surrounding sclerosing hemangioma of the lung.

We present two cases of sclerosing hemangioma of the lung with a peculiar radiologic finding: an air-trapping zone surrounding the tumor. On microscopic examinations, the tumor was of the hemangiomatous subtype, and the radiolucent zone corresponded to enlarged alveoli with septal destruction. A possible mechanism in the production of an air-trapping zone around a sclerosing hemangioma is bleeding from the highly vascular tumor followed by expectoration in communication with an airway.

The usefulness of MR imaging of the temporal bone in the evaluation of patients with facial and audiovestibular dysfunction.

Objective: To evaluate the clinical utility of MR imaging of the temporal bone in patients with facial and audiovestibular dysfunction with particular emphasis on the importance of contrast enhancement.

Materials And Methods: We retrospectively reviewed the MR images of 179 patients [72 men, 107 women; average age, 44 (range, 1-77) years] who presented with peripheral facial palsy (n=15), audiometrically proven sensorineural hearing loss (n=104), vertigo (n=109), or tinnitus (n=92). Positive MR imaging findings possibly responsible for the patients' clinical manifestations were categorized according to the anatomic sites and presumed etiologies of the lesions.

Regulation of thioredoxin peroxidase activity by C-terminal truncation.

Thioredoxin peroxidase is a member of peroxiredoxin (Prx) family, which uses a thioredoxin (Trx) as an immediate electron donor for the reduction of peroxide. We have identified C-terminal truncated TPx from Schizosaccharomyces pombe and also have found the truncated form is significantly tenacious against the inactivation of H2O2 than the intact form. Peroxidase assay of a series of recombinant C-terminal truncation mutants (Delta192, Delta191, Delta188, Delta184, Delta176, and Delta165) revealed that TPx could be inactivated (Delta192), reactivated (Delta191-Delta176) and reinactivated (Delta165) by serial truncation from C-terminus.

Acute effects of serotonin on rat bladder contractility.

Introduction: The purpose of this study is to investigate in vitro the effects of serotonin on the rat detrusor. In particular, it examines which drugs inhibit the serotonin-induced detrusor contractions.

Materials And Methods: Isometric tension changes of isolated rat bladder muscle strips were recorded in an organ bath using a force transducer.