Prevalence of neutralising antibodies to interferon-beta and clinical response in Chinese patients with relapsing multiple sclerosis.

BACKGROUND: There are no data on neutralising antibodies to interferon-beta and its clinical implications in Chinese patients with multiple sclerosis (MS). OBJECTIVES: The objectives of this study were to investigate the prevalence of neutralising antibodies among Chinese patients with relapsing MS receiving interferon-beta (1a or 1b) and to study the association between neutralising antibodies and the clinical-radiological response. METHODS: We performed a cross-sectional study on MS patients who received interferon-beta for 9 months or more, and evaluated the clinical response by relapses and magnetic resonance imaging lesions. Blood samples were evaluated for myxovirus resistance protein A (MxA) gene expression by polymerase chain reaction, anti-interferon-beta binding antibodies by enzyme-linked immunosorbent assay, and neutralising antibodies by cell-based MxA protein induction and luciferase reporter gene assays. Assay performances were evaluated by receiver operating characteristic analysis. RESULTS: Among 78 subjects recruited, 61/77 (79%) had anti-interferon-beta binding antibodies, and 22/78 (28%) had neutralising antibodies by MxA protein induction assay. The presence of high-titre neutralising antibodies was associated with poor clinical outcome (odds ratio 6.1, 95% confidence interval 1.5-25.6, P = 0.013). The sensitivity and specificity for neutralising antibodies using MxA gene expression assay (cut-off 0.20) was 80% and 68%, respectively (area under the curve 0.71). CONCLUSIONS: Neutralising antibodies are associated with poor clinical outcome in Chinese patients with relapsing MS. MxA gene expression and protein induction assays are complimentary assays for neutralising antibody detection.

The effect of low-energy laser irradiation on apoptotic factors following experimentally induced transient cerebral ischemia.

Apoptosis, or programmed cell death, resulting from cerebral ischemia may be related to decreased levels of anti-apoptotic factors, such as serine/threonine kinase (Akt), phosphorylated Akt (pAkt), pBAD, and Bcl-2, and increased levels of pro-apoptotic factors, such as BAD, caspase 9, and caspase 3 activities. In this study, we investigated the effects of low-energy laser (660 nm) irradiation (LLI) on the levels and activity of various anti- and pro-apoptotic factors following ischemia. Transient cerebral ischemia was induced in Sprague-Dawley rats by unilateral occlusion of the middle cerebral artery for 1 h, followed by reperfusion. LLI was then directed on the cerebrum for varying lengths of duration (1, 5, or 10 min at an energy density of 2.64 J/cm², 13.2 J/cm², and 24.6 J/cm², respectively). The expression levels of Akt, pAkt, BAD, pBAD, Bcl-2, caspase 9, and caspase 3 activities were measured 4 days after injury. The levels of Akt, pAkt, Bcl-2, and pBAD were significantly increased following laser irradiation. In addition, LLI significantly decreased caspase 9 and caspase 3 activities caused by ischemia-reperfusion. LLI may protect the brain by upregulating Akt, pAkt, pBAD, and Bcl-2 expression and downregulating caspase 9 and caspase 3 expression following transient cerebral ischemia. This modality is a promising protective therapeutic intervention after strokes or other ischemic events.

Anti-N-methyl-D-aspartate receptor encephalitis in a young woman with an ovarian tumour.

Anti-N-methyl-D-aspartate receptor encephalitis is characterised by psychiatric and neurological abnormalities and occurs in frequent association with ovarian teratoma. We report the first confirmed case of teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis in Hong Kong in a young woman presenting with confusion and prominent dyskinesia, followed by a review of the current literature.

Lithium overdose causing non-convulsive status epilepticus--the importance of lithium levels and the electroencephalography in diagnosis.

We report a case of lithium overdose in a patient who presented in non-convulsive status epilepticus. The lithium toxicity was probably due to interaction with Moduretic. The diagnosis was not suspected until electroencephalography was performed. This case underscores the importance of therapeutic drug level monitoring of lithium, especially where toxicity is suspected, and the indispensable role electroencephalography plays by allowing a correct diagnosis to be made promptly.

Therapeutic ultrasound enhances medial collateral ligament repair in rats.

The purpose of this study was to evaluate the effects of therapeutic ultrasound (US) on medial collateral ligament healing. A total of 36 3-month-old male Sprague-Dawley rats with transected medial collateral ligaments were studied. Subjects were given 5-min pulsed US therapy (duty cycle; one application in 4 ms; 1:4) daily with different durations (1 day, 5 days and 10 days) and intensities (0, 0.5 and 2.3 W/cm2). After each treatment, the level of transforming growth factor beta-1 (TGF-beta1) of the ligament was measured. TGF-beta1 was not detected in the 1-day group. In the 5-day and 10-day groups, the levels of TGF-beta1 were significantly up-regulated in the high-dose subgroup (p < 0.05). The 10-day group also registered a significantly higher expression of TGF-beta1 than did the 5-day group (p < 0.05). The present findings suggest that pulsed US therapy may enhance ligament repair by up-regulating the extent of TGF-beta1 in a high-dose application. Long-term treatment with this therapy could obtain further improvement.

A case of tetramine poisoning: a lethal rodenticide.

We report a fatal case of suicide presenting with convulsions and subsequently multi-organ failure. Rodenticide poisoning was not suspected until the next day when tetramine was detected in the patient's blood, urine, and food residues. Tetramine is a potent rodenticide with a rapid action and high mortality. The poison has been banned worldwide but is still readily available in Mainland China. Outbreaks of poisoning are reported frequently and doctors should be alert for this lethal toxin.

Effect of ultrasound on acute inflammation of transected medial collateral ligaments.

OBJECTIVE: To evaluate the effect of therapeutic ultrasound on the acute inflammation of soft-tissue injuries by measuring the levels of prostaglandin E(2) (PGE(2)) and leukotriene B(4) (LTB(4)). DESIGN: Randomized, case-control study. SETTING: Laboratory animal facility. ANIMALS: Thirty 3-month-old male Sprague-Dawley rats. INTERVENTION: Rats with medial collateral ligament transection were given 5 minutes of pulsed ultrasound therapy (1:4) daily, with different durations (1, 5, 10d) and intensities (0, 0.5, 1.5, 2.3W/cm(2)). MAIN OUTCOME MEASURES: Levels of PGE(2) and LTB(4). RESULTS: The levels of PGE(2) and LTB(4) were higher in all intensity subgroups that received 2.3W/cm(2) intensity on postinjury day 2. On postinjury day 11, LTB(4) was significantly decreased, but PGE(2) was significantly increased. CONCLUSIONS: Pulsed ultrasound therapy may stimulate inflammation of acute ligament injury.

Creatine kinase MB elevation in paralytic shellfish poisoning.

An outbreak of paralytic shellfish poisoning occurred in southern Taiwan, affecting 116 persons who had consumed purple clams. Two victims died within four hours. Gonyautoxins were identified as causative toxins. During the outbreak, five patients with paralytic shellfish poisoning were seen in our hospital. All recovered following supportive treatments. Serum creatine kinase concentration was elevated in three of the five patients. The levels of the enzyme did not seem to correlate with the severity of poisoning. The most significant finding was the previously unreported observation of elevation of the creatine kinase MB level. In all four patients who had creatine kinase MB value determined, it was elevated.

Hepatitis D virus infection among intravenous drug abusers in Taiwan: analysis of risk factors and liver function tests.

To investigate the prevalence of hepatitis D virus (HDV) and hepatitis B virus (HBV) infection among intravenous drug abusers in Taiwan, a total of 761 male prisoners, including 680 intravenous drug abusers, were studied for serological markers of HBV and HDV. Questionnaires were distributed to evaluate the risk factors for HDV infection and also to estimate the strength of association among HDV infection and the risk factors. HBV infection was common, and the positive rates of HBV markers between intravenous drug abusers and non-drug abusers were not statistically different. However, the positive rate of the antibody to HDV was significantly higher among intravenous drug abusers than among non-drug abusers (21.3% vs. 8.6%). Of 131 chronic HBV carriers with intravenous drug abuse, 119 (91%) were anti-HD positive. Using multiple logistic regression models, we found that the most important risk factor for HDV infection was hepatitis B surface antigen (HBsAg) carriage, and intravenous drug addiction the next. A matched case-control study also was conducted to compare liver function tests among both anti-HD- and HBsAg-positive group anti-HD-negative, and HBs-AG-positive group as well as those with neither positive. Statistically significant difference in liver function tests was not found. It is concluded that the HBsAg carriers with intravenous drug abuse in Taiwan are commonly HDV infected with and that the infection does not seem to affect the liver as assessed by liver function tests.