Hydrocarbon exposure and Parkinson's disease

BACKGROUND: Single cases of parkinsonism have been associated with hydrocarbon solvents. OBJECTIVE: To determine whether exposure to hydrocarbon solvents is related to PD. METHODS: Cohort study of 990 patients with PD according to Core Assessment Program for Intracerebral Transplantations (CAPIT) criteria, selected from 1455 consecutive subjects presenting at a referral center; case-control study assessing Unified PD Rating Scale scores (motor score as primary endpoint) in all subjects with positive history of hydrocarbon solvent exposure (n = 188), matched for duration of disease and gender to 188 subjects selected from the remaining 802 with a negative history. Two subgroups in the case-control study included the following: 1) response to apomorphine (n = 26); 2) brain MRI (n = 15). PET imaging (n = 9) was compared with that of historic controls. RESULTS: Exposed patients were younger (61.0 +/- 9.4 versus 64.7 +/- 9.4 years, p = 0.002), predominantly male (76.4% versus 45.2%, p = 0.0001), less educated (8.4 +/- 4.2 versus 10.1 +/- 4.4 years, p = 0.0001), and younger at onset of disease (55.2 +/- 9.8 versus 58.6 +/- 10 years, p = 0.014). Exposure to hydrocarbon solvents directly correlated to disease severity (r = 0. 311) and inversely correlated to latency period (r = -0.252). Nine blue-collar occupations accounted for 91.1% of exposures. CONCLUSIONS: Occupations involving the use of hydrocarbon solvents are a risk factor for earlier onset of symptoms of PD and more severe disease throughout its course. Hydrocarbon solvents may be involved in the etiopathogenesis of PD, which does not have a major genetic component.     

Parkinson disease

Parkinson disease (PD) is the most common neurodegenerative movement disorder. In Europe, prevalence and incidence rates for PD are estimated at approximately 108–257/100 000 and 11–19/100 000 per year, respectively. Risk factors include age, male gender and some environmental factors. The aetiology of the disease in most patients is unknown, but different genetic causes have been identified. Although familial forms of PD account for only 5%–15% of cases, studies on these families provided interesting insight on the genetics and the pathogenesis of the disease allowing the identification of genes implicated in its pathogenesis and offering critical insights into the mechanisms of disease. The cardinal motor symptoms of PD are tremor, rigidity, bradykinesia/akinesia and postural instability, but the clinical picture includes other motor and non‐motor symptoms. Its diagnosis is principally clinical, although specific investigations can help the differential diagnosis from other forms of parkinsonism. Pathologically, PD is characterized by the loss of dopaminergic neurons in the pars compacta of the substantia nigra and by accumulation of misfolded α‐synuclein, which is found in intra‐cytoplasmic inclusions called Lewy bodies. Currently available treatments offer good control of motor symptoms but do not modify the evolution of the disease. This article is intended to provide a comprehensive, general and practical review of PD for the general neurologist.     

Trichloroethylene and Parkinson disease

Multiple genetic and environmental etiologies have been implicated in the pathogenesis of idiopathic Parkinson disease. Recent observations have suggested an association between chronic exposure to trichloroethylene (TCE) and development of clinical parkinsonism. Animal models of TCE exposure have shown nigrostriatal degeneration and the development of parkinsonian features. Animal and cell culture models indicate mitochondrial dysfunction as the probable mechanism, most likely mediated by TaClo, a potential TCE metabolite. These observations endorse the hypothesis that a variety of environmental risk factors may cause nigrostriatal degeneration and clinical parkinsonism in genetically predisposed individuals.     

帕金森病与妊娠

帕金森病（PD）是最常见的运动障碍疾病之一,然而PD 患者妊娠较少见。女性在妊娠期间的PD患病率较低,存在症状波动时其药物选择困难,不良反应较多且复杂。随着产妇平均生育年龄的增长,PD 合并妊娠的现象日益普遍。现从妊娠对PD的影响、抗PD 药物的选择及对胎儿的影响、深部脑刺激术、母乳喂养及预后逐一进行阐述     

Alpha-synuclein and Parkinson disease

OBJECTIVE:To review the recent progresses on the studies ofα-synuclein in the pathogenesis of Parkinson disease(PD)and look into the perspective ofα-synuclein as a new therapy target.DATA SOURCES:To search the literatures on the progresses of PD studies,especially on the structure,gene expression of α-synuclein and the pathogenesis of PD in Medline from January 1998 to February 2007.Search terms were “Parkinson's disease,α-synuclein” in English.STUDY SELECTION:Initial check the data and choose the original and review articles directly linked to the role of α-synuclein in PD pathogenesis and screening out indirectly discussing articles.Collect the full text and trace the quoting articles and the quoted articles.Only the latest reviews were chosen in Chinese articles.DATA EXTRACTION:There were 424 articles on α-synuclein and its role in the pathogenesis of PD and 43 articles directly related withα-synuclein were chosen among which 12 were reviews.DATA SYNTHESIS:α-synuclein is a kind of soluble protein expressed in pre-synapse in central nervous system encoded by gene in homologous chromosome 4q21.It has physiological function in modulating the stability of membrane and neural plasticity.There is a close relationship between gene mutation inα-synuclein and the pathogenesis of PD.Environmental and genetic factors can induce the misfolding ofα-synuclein,and secondary structural change can result in oligomer formation which induces a series of cascade reaction to damage dopaminergic system subsequently.Cell and animal transgenic and non-transgenic models are established recently and the important role of α-synuclein in the pathogenesis both of familial and sporadic PD is confirmed.Studies reveal that inhibiting the aggregation of α-synuclein can prevent its neurotoxicity;gene parkin can intercept the cell death pathway triggered by the aggregation ofα-synuclein in cytoplasm.CONCLUSION:Gene mutation ofα-synuclein and the impairment in its structure and function are importan in the pathogenesis of PD.Intervention of the gene mutations and abnormal protein aggregation ofα-synuclein may be a new strategy for preventing and treating PD.     

Alcohol and Parkinson disease

A survey of the drinking habits of 125 patients with idiopathic Parkinson disease showed no difference from a control population in the amount of alcohol consumed and only mild effects of alcohol on parkinsonian symptoms in a small percentage (16%) of these patients. A case of parkinsonism provoked by alcohol withdrawl is also reported, and the complex effects of alcohol on function of the basal ganglia are briefly reviewed.