Magnesium (Mg) is an essential mineral element for plants and is nontoxic to organisms. In this study, we took advantage of nanotechnologies to systematically investigate the antibacterial mechanisms of magnesium oxide nanoparticles (MgONPs) against the phytopathogen Ralstonia solanacearum (R. solanacearum) in vitro and in vivo for the first time. R. solanacearum has contributed to catastrophic bacterial wilt, which has resulted in the world-wide reduction of tobacco production. The results demonstrated that MgONPs possessed statistically significant concentration-dependent antibacterial activity, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured as 200 and 250 μg/mL, respectively. Additional studies, aimed at understanding the toxicity mechanism of MgONPs, indicated that physical injury occurred to the cell membranes, along with decreased motility and biofilm formation ability of R. solanacearum, due to the direct attachment of MgONPs to the surfaces of the bacterial cells, which was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Reactive oxygen species (ROS) accumulation could also be an important reason for the antibacterial action, inducing DNA damage. The toxicity assessment assay under greenhouse conditions demonstrated that the MgONPs had exerted a large effect on tobacco bacterial wilt, reducing the bacterial wilt index. Altogether, the results suggest that the development of MgONPs as alternative antibacterial agents will become a new research subject.

Acute extrapyramidal movement disorders have rarely been reported in uremic patients. We had previously presented three cases of acute movement disorders with bilateral basal ganglia lesions in uremia, and had proposed that it is not a rare condition. The objective of this study is to establish a more accurate clinical profile of this rarely described clinical syndrome, and to call attention to its common occurrence. We prospectively studied six patients we encountered from March 1996 to June 2001. We also reviewed the clinical records of a large population of uremic patients and identified six more cases. The clinical manifestations, laboratory findings, neuroimages, and clinical outcomes of these 12 patients were analyzed. When possible, each patient was followed up to the present time. Twelve patients had acute onset of movement disorders and bilateral basal ganglia lesions. All of the patients were diabetic. They had acute-onset Parkinsonism or dyskinesias, together with various symptoms such as consciousness disturbance, dysarthria, dysphagia, or ataxia. The main laboratory test results of abnormalities consisted of elevated blood urea nitrogen, creatinine, and metabolic acidosis. They had uniform neuroimaging findings of symmetrical bilateral basal ganglion changes. These changes regressed or disappeared during follow-up. The clinical prognoses were diverse. We believe that this group of patients represents a well-demarcated clinical syndrome, which is not uncommon but has previously been rarely addressed. The underlying mechanism of such lesions may be associated with metabolic, as well as vascular factors.

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Hyperglycemia-induced unilateral basal ganglion lesions occur mostly in Asian patients. A signal abnormality in the basal ganglion region is evident on these patients' neuroimaging. Despite characteristic imaging findings and clinical manifestations, the underlying mechanism is still unclear. To clarify the underlying pathophysiology of unilateral basal ganglion lesions, we examined the [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) findings in 3 patients with hyperglycemia. The PET studies were performed at 3 weeks, 5 weeks, and 7 months after clinical onset. The markedly reduced rates of cerebral glucose metabolism in the corresponding lesions on T1-weighted magnetic resonance images provided direct evidence of regional metabolic failure. We suggest that the metabolic derangements associated with hyperglycemia and vascular insufficiency contribute to regional metabolic failure in patients with poorly controlled diabetes mellitus.