Neuroscience letters
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Neuroscience letters · Nov 2021
The effect of intermittent theta burst stimulation on corticomotor excitability of the biceps brachii in nonimpaired individuals.
Intermittent theta burst stimulation (iTBS) is a form of repetitive transcranial magnetic stimulation (TMS) that can increase corticomotor excitability in distal upper limb muscles, but the effect on the more proximal biceps is unknown. The study objective was to determine the effect of iTBS on corticomotor excitability of the biceps brachii in non-impaired individuals. Ten individuals completed three sessions, and an additional ten individuals completed one session in a secondary study; each session included sham and active iTBS. ⋯ Our results suggest that when RMTs are expected to be high when measured with biphasic stimulation, monophasic stimulation can better capture changes in MEPs induced by iTBS, and biphasic stimulation appears limited in its ability to capture changes in biceps MEPs in nonimpaired individuals. In both cohorts, increased corticomotor excitability after iTBS occurred when the biceps AMT:RMT ratio was high. Thus, the AMT:RMT ratio may be a predictive measure to evaluate the potential for iTBS to increase biceps corticomotor excitability.
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Neuroscience letters · Apr 2021
Insulin-like growth factor-1 inhibits nitroglycerin-induced trigeminal activation of oxidative stress, calcitonin gene-related peptide and c-Fos expression.
Migraineurs experience increased oxidative stress which drives the initiation and maintenance of migraine-related pain in animal models and, by extension, migraine in humans. Oxidative stress augments calcitonin gene-related peptide (CGRP) levels, a mediator of migraine pain. Insulin-like growth factor-1 (IGF-1), a neuroprotective growth factor, reduces susceptibility to spreading depression, a preclinical model of migraine, in cultured brain slices by blocking oxidative stress and neuroinflammation from microglia. ⋯ These effects were significantly reduced at all doses of IGF-1 for trigeminal ganglion metrics of oxidative stress and CGRP and only at the lowest dose in both males and females for c-Fos. The latter inverted U-shaped or hormetic response is seen in enzyme-targeting drugs. While the specific mechanisms remain to be explored, our data here supports the ability of IGF-1 to preserve mitochondrial and antioxidant pathway homeostasis as means to prevent nociceptive activation in the trigeminal system produced by an experimental migraine model.
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Neuroscience letters · Apr 2021
Review Case ReportsNeurological issues during severe COVID-19 in a tertiary level hospital in Western India.
India has the second largest COVID-19 epidemic in the world as per current estimates. Central and peripheral nervous system involvement in COVID-19 (Neuro COVID-19) has been increasingly identified and reported. This letter is the first report of the spectrum of neurological disorders observed in patients with severe COVID-19 from a resource limited setting like India. ⋯ Encephalopathy (22/423, 5.2 %) and new onset large vessel ischemic stroke secondary to cerebral artery thrombosis (5/423, 1.1%) were the most common secondary neurologic complications noted in our cohort. Two cases of COVID-19/central nervous system tuberculosis co-infection were also identified. CHALLENGES IN MANAGEMENT OF NEURO COVID-19 IN INDIA: Various challenges like an overwhelmed health care system, inadequate workforce, lack of exhaustive reporting of symptoms and poor availability of neuroimaging in ventilated COVID-19 patients leads to underestimation of Neuro COVID-19 in resource limited settings like India.
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Neuroscience letters · Mar 2021
Brain activity alterations in patients with Parkinson's disease with cognitive impairment based on resting-state functional MRI.
This study aimed to investigate the differences in regional homogeneity (ReHo) values in patients with Parkinson's disease (PD) with cognitive impairment (PD-CI) and thus explore the neuropathological mechanism of PD-CI. ⋯ Age was a risk factor for cognitive decline in patients with PD. The ReHo value in the default mode network (DMN) was closely related to PD cognitive function, and the DMN was affected before CI and continuously deteriorated with disease progression. The disorder of visual conduction pathway was involved in CI in patients with PD, but these patients could recruit cognitive resources by improving visual-spatial ability. The cognitive function in such patients was related to the dopaminergic, cholinergic, and noradrenergic systems. The information transmission efficiency of the cerebellum-thalamus-cortex loop was reduced and involved in the cognitive decline process in patients with PD.
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Neuroscience letters · Feb 2021
ReviewOpioids and cancer prognosis: A summary of the clinical evidence.
Pain is a common and devastating symptom among cancer patients. It can be caused by the cancer itself or by certain therapies like surgery, radiation or chemotherapy. Opioids are the first line of treatment for moderate to severe cancer-related pain. ⋯ Retrospective studies suggest an association between the expression of MOR in cancers and shorter survival. In addition, recent evidence suggests that opium use and prescription opioids can influence clinical oncological outcomes. In this review, we will summarize the clinical evidence regarding the effect of opioid administration and survival in patients with cancer as well as the current evidence involving MOR expression and cancer progression.