Panscleritis After Blunt Ocular Trauma in A Child with Epididymitis / 中国医学科学杂志(英文版)

We reported an 8-year-old boy with panscleritis in left eye and right epididymitis after falling on the ground. Etiologic diagnosis played a key role in this case. Systemic examinations ruled out systemic autoimmune diseases, tumors, and infections as the cause of scleritis and suggested that the disease was caused by a local delayed-type hypersensitivity (DTH) induced by ocular trauma and was non-infectious. Still, the right epididymitis was infectious. Both conditions were treated successfully using steroids and antibiotics, respectively. Thus, early etiologic diagnosis and reasonable treatment are crucial to prevent visual loss.

Excess nicotinamide increases plasma serotonin and histamine levels / 生理学报

Methylation, a methyl group-consuming reaction, plays a key role in the degradation (i.e., inactivation) of monoamine neurotransmitters, including catecholamines, serotonin and histamine. Without labile methyl groups, the methylation-mediated degradation cannot take place. Although high niacin (nicotinic acid and nicotinamide) intake, which is very common nowadays, is known to deplete the body's methyl-group pool, its effect on monoamine-neurotransmitter degradation is not well understood. The aim of this article was to investigate the effect of excess nicotinamide on the levels of plasma serotonin and histamine in healthy subjects. Urine and venous blood samples were collected from nine healthy male volunteers before and after oral loading with 100 mg nicotinamide. Plasma N(1)-methylnicotinamide, urinary N(1)-methyl-2-pyridone-5-carboxamide (2-Py), and plasma betaine levels were measured by using high-performance liquid chromatography (HPLC). Plasma concentrations of choline, serotonin and histamine were measured using commercial kits. The results showed that the plasma N(1)-methylnicotinamide level and the urinary excretion of 2-Py significantly increased after oral loading with 100 mg nicotinamide, which was accompanied with a decrease in the methyl-group donor betaine. Compared with those before nicotinamide load, five-hour postload plasma serotonin and histamine levels significantly increased. These results suggest that excess nicotinamide can disturb monoamine-neurotransmitter metabolism. These findings may be of significance in understanding the etiology of monoamine-related mental diseases, such as schizophrenia and autism (a neurodevelopmental disorder).