RESUMO
Early detection and drug intervention with the appropriate timing and dosage are the main clinical challenges for ischemic stroke (IS) treatment. The conventional therapeutic agents relay fluorescent signals, which require real-time external light excitation, thereby leading to inevitable autofluorescence and poor tissue penetration. Herein, we report endogenous peroxynitrite (ONOO-)-activated BDP-4/Cur-CL NPs that release NIR afterglow signals (λmax 697 nm) for real-time monitoring of the progression of ischemia reperfusion (I/R) brain injury while releasing curcumin for the safe treatment of IS. The BDP-4/Cur-CL NPs exhibited bright NIR afterglow luminescence (maximum 732-fold increase), superb sensitivity (LOD = 82.67 nM), high energy-transfer efficiency (94.6%), deep tissue penetration (20 mm), outstanding antiapoptosis, and anti-inflammatory effects. The activated NIR afterglow signal obtained in mice with middle cerebral artery occlusion (MCAO) showed three functions: (i) the BDP-4/Cur-CL NPs are rapidly activated by endogenous ONOO-, instantly illuminating the lesion area, distinguishing I/R damage from normal areas, which can be successfully used for endogenous ONOO- detection in the early stage of IS; (ii) real-time reporting of in situ generation and dynamic fluctuations of endogenous ONOO- levels in the lesion area, which is of great value in monitoring the evolutionary mechanisms of IS; and (iii) dynamic monitoring of the release of curcumin drug for safe treatment. Indeed, the released curcumin effectively decreased apoptosis, enhanced survival, alleviated neuroinflammation, reduced brain tissue loss, and improved the cognition of MCAO stroke mice. This work is the first example of afterglow luminescence for early diagnosis, real-time reporting, drug tracing, and treatment for IS.
Assuntos
Curcumina , AVC Isquêmico , Nanopartículas , Camundongos , Animais , AVC Isquêmico/tratamento farmacológico , Curcumina/farmacologia , Curcumina/uso terapêutico , Luminescência , EncéfaloRESUMO
BACKGROUND: Subacute combined degeneration (SCD) is a demyelinating disease characterized by vitamin B12 deficiency related segmental degeneration of the dorsal or lateral columns of the spinal cord. However, few cases have been reported as a comorbidity of SCD and neuromyelitis optica spectrum disease (NMOSD). CASE PRESENTATION: Herein, we describe a female patient (61-year-old) who had sensory deficits, paresthesia, and weakness of the distal extremities for over 2 months. She then received an initial diagnosis of SCD with typical inverted "V-sigh" hyperintensities over the posterior aspect of the spinal cord in magnetic resonance imaging (MRI - T2-weighted imaging), as well as megaloblastic anaemia in blood examinations. From the past history, there was no evidence of a dietary deficiency or gastric abnormalities. However, traditional treatment with vitamin B12 supplementation was ineffective. Hence, a demyelinating antibody examination showed that she had antibodies targeting aquaporin 4 (AQP4) in both the cerebrospinal fluid and serum, leading to the diagnosis of NMOSD. Her clinical symptoms were obviously improved after treatment with intravenous glucocorticoids. CONCLUSION: People who have nutritional deficiency or altered gastrointestinal function are more likely to develop SCD. This case raises the awareness that the poor therapeutic effects of simple vitamin B12 supplementation could be explained by immunoreactions against AQP4. A better recognition will be of great importance for the correct diagnosis of the comorbidity, as well as for essential treatment and even a better prognosis.
Assuntos
Neuromielite Óptica , Degeneração Combinada Subaguda , Aquaporina 4 , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuromielite Óptica/complicações , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/tratamento farmacológico , Degeneração Combinada Subaguda/tratamento farmacológico , Degeneração Combinada Subaguda/etiologia , Vitamina B 12/uso terapêuticoRESUMO
The efficacy of neurofeedback is a point of great controversy, because a certain proportion of users cannot properly regulate their brain activities and thereby fail to benefit from neurofeedback. To address the neurofeedback inefficacy problem, the present study is aimed to design and implement a new neurofeedback system that can more effectively and consistently regulate users' brain activities than the conventional way of training users to voluntarily regulate brain activities. The new neurofeedback system delivers external visual stimuli continuously at a specific alpha phase, which is real-time decoded from ongoing alpha wave, to regulate the alpha wave. Experimental results show that the proposed training-free externally-regulated neurofeedback (ER-NF) system can achieve consistent (effective in almost all sessions for almost all users), flexible (either increasing or decreasing peak alpha frequency and alpha power), and immediate (taking or losing effect immediately after stimulation is on or off) modulation effects on alpha wave. Therefore, the ER-NF system holds great potential to be able to more reliably and flexibly modulate cognition and behavior.
Assuntos
Ritmo alfa/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Neurorretroalimentação/métodos , Estimulação Luminosa/métodos , Autocontrole , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Neurorretroalimentação/instrumentação , Adulto JovemRESUMO
OBJECTIVES: Oxygen therapy has been long considered a logical therapy for ischemic stroke. Our previous studies showed that normobaric hyperoxia (normobaric hyperoxia (NBO), 95% O2 with 5% CO2) treatment during ischemia reduced ischemic neuronal death and cerebromicrovascular injury in animal stroke models. In this study, we studied the effects of NBO on the evolution of ischemic brain tissue to infarction in a rat model of transient focal cerebral ischemia. METHODS: Male Sprague-Dawley rats were given NBO (95% O2) or normoxia (21% O2) during 90-min filament occlusion of the middle cerebral artery (MCAO), followed by 3 or 22.5 h of reperfusion. 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to evaluate the longitudinal evolution of tissue infarction. Resultsï¼ In normoxic rats, MCA-supplied cortical and striatal tissue was infarcted after 90-min MCAO with 22.5 h of reperfusion. NBO-treated rats showed a 61.4% reduction in infarct size and tissue infarction mainly occurred in the ischemic striatum. When infarction was assessed at an earlier time point, i.e. at 3 h of reperfusion, normoxic rats showed significantly smaller but mature infarction (no TTC staining, white color), with the infarction mainly occurring in the striatum. Unexpectedly, NBO-treated rats only showed immature lesion (partially stained by TTC, light white color) in the ischemic striatum, indicating that NBO treatment also retarded the process of neuronal death in the ischemic core. Of note, NBO-preserved striatal tissue underwent infarction after prolonged reperfusion. Conclusionsï¼ Our results demonstrate that NBO treatment given during cerebral ischemia retards the evolution of ischemic brain tissue toward infarction and NBO-preserved cortical tissue survives better than NBO-preserved striatal tissue during the phase of reperfusion.