Central nervous system stimulation therapies in phantom limb pain:a systematic review of clinical trials

Phantom limb pain is a chronic pain syndrome that is difficult to cope with.Despite neurostimulation treatment is indicated for refractory neuropathic pain,there is scant evidence from randomized controlled trials to recommend it as the treatment choice.Thus,a systematic review was performed to analyze the efficacy of central nervous system stimulation therapies as a strategy for pain management in patients with phantom limb pain.A literature search for studies conducted between 1970 and September 2020 was carried out using the MEDLINE and Embase databases.Principles of The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline were followed.There were a total of 10 full-text articles retrieved and included in this review.Deep brain stimulation,repetitive transcranial magnetic stimulation,transcranial direct current stimulation,and motor cortex stimulation were the treatment strategies used in the selected clinical trials.Repetitive transcranial magnetic stimulation and transcranial direct current stimulation were effective therapies to reduce pain perception,as well as to relieve anxiety and depression symptoms in phantom limb pain patients.Conversely,invasive approaches were considered the last treatment option as evidence in deep brain stimulation and motor cortex stimulation suggests that the value of phantom limb pain treatment remains controversial.However,the findings on use of these treatment strategies in other forms of neuropathic pain suggest that these invasive approaches could be a potential option for phantom limb pain patients.

Elevated thyroid stimulating hormone levels are associated with metabolic syndrome in a Chinese community-based population of euthyroid people aged 40 years and older

This study investigated whether high-normal thyrotropin（TSH） levels are associated with metabolic syndrome in euthyroid Chinese people≥40 years old.Clinical and metabolic factors were assessed in 2,356 subjects（40-77 years old） with TSH levels in the normal range（0.35-5.00 mU/L）.Using 2.50 mU/L as the cut-off point of TSH level within the normal range,we divided subjects into the high-TSH（2.50-5.00 mU/L;n= 1,064） and low-TSH（0.35-2.50mU/L;n= 1,292） group.The results showed that the mean levels of body mass index（BMI）,total cholesterol（TC）,low density lipoprotein cholesterol（LDL-C）,and fasting plasma glucose（FPG） were higher in the high-TSH group and TSH levels were significantly positively con-elated with BMI,LDL-C,TC,and FPG.The prevalence of central obesity,hypertriglyceridemia,low high density lipoprotein cholesterol（HDL-C）,and high FPG（〉5.60 mmol/L） was significantly higher in females and subjects with high-TSH levels.Metabolic syndrome was also more prevalent in the high-TSH group.People over the age of 40 years with high-normal TSH levels had a 1.2-fold increased risk of metabolic syndrome,compared with those with low-normal TSII levels,after adjusting for age and gender.In conclusion,high normal TSH is a risk factor for metabolic syndrome in people ≥40 years old.

Long-term potentiation in autonomic ganglia:Potential role in cardiovascular disorders

Ganglionic long-term potentiation(gLTP) is an activitydependent,enduring enhancement of ganglionic transmission.This phenomenon may be induced in autonomic ganglia of an organism under certain conditions whererepetitive impulses surge from the central nervous system(CNS) to the periphery.Chronic stress,repetitive epileptic seizure or chronic use of CNS stimulants could induce gL TP,which would result in a long lasting heightening of sympathetic tone to the cardiovascular system causing hypertension and disturbed cardiac rhythm that may lead to sudden cardiac death.These conditions are briefly reviewed in this article.