Environmental Endocrine Disruptors and Neurological Disorders

We live in a world where daily exposure to environmental chemicals is inevitable. Many studies point to environmental chemicals a major cause of neurological diseases. Properly intervening in and managing the exposure requires up-to-date information about neurotoxic chemicals that may lead to neurological disorders. The recent literature on the neurotoxic effects of environmental chemicals was reviewed, including both animal and human studies. Parkinson's disease, Alzheimer's disease and autism are closely associated with environmental chemicals such as polychlorinated biphenys (PCBs), dioxins, polybrominated biphenyl ethers (PBDE), and perfluoroalkyls. There is strong evidence linking environmental chemical exposure to neurodevelopmental and neurodegenerative diseases. In particular, it is important to pay close attention to a high risk-age group where the window of exposure is critical to causing neurological disease.

Erratum: Comparison between Clinical Disabilities and Electrophysiological Values in Charcot-Marie-Tooth 1A Patients with PMP22 Duplication

The publisher wishes to apologize for incorrectly displaying the author (Seok Beom Gwon) name. We correct his name from Seok Beom Gwon to Seok Beom Kwon.

Comparison between Clinical Disabilities and Electrophysiological Values in Charcot-Marie-Tooth 1A Patients with PMP22 Duplication

BACKGROUND AND PURPOSE: Charcot-Marie-Tooth disease (CMT) type 1A (CMT1A) is the demyelinating form of CMT that is significantly associated with PMP22 duplication. Some studies have found that the disease-related disabilities of these patients are correlated with their compound muscle action potentials (CMAPs), while others have suggested that they are related to the nerve conduction velocities. In the present study, we investigated the correlations between the disease-related disabilities and the electrophysiological values in a large cohort of Korean CMT1A patients. METHODS: We analyzed 167 CMT1A patients of Korean origin with PMP22 duplication using clinical and electrophysiological assessments, including the CMT neuropathy score and the functional disability scale. RESULTS: Clinical motor disabilities were significantly correlated with the CMAPs but not the motor nerve conduction velocities (MNCVs). Moreover, the observed sensory impairments matched the corresponding reductions in the sensory nerve action potentials (SNAPs) but not with slowing of the sensory nerve conduction velocities (SNCVs). In addition, CMAPs were strongly correlated with the disease duration but not with the age at onset. The terminal latency index did not differ between CMT1A patients and healthy controls. CONCLUSIONS: In CMT1A patients, disease-related disabilities such as muscle wasting and sensory impairment were strongly correlated with CMAPs and SNAPs but not with the MNCVs or SNCVs. Therefore, we suggest that the clinical disabilities of CMT patients are determined by the extent of axonal dysfunction.

Serum Homocysteine and Its Relevant Factors among Health Screeners in a University Hospital

BACKGROUND: Elevated plasma total homocysteine is a risk factor for cardiovascular diseases. The authors investigated the parameters such as habit, body index, cardiovascular risk factors, nutrition relative to the plasma homocysteine concentration. METHODS: The subjects were 6,223 adults (3,377 males, 2,846 females) who were over 18 years of age and visited a health promotion center of a university hospital from March 2002 to January 2003. We assessed the relationship between the homocysteine level and the following parameters: sex, age, weight, body mass index, waist circumference, smoking, alcohol, systolic and diastolic blood pressure (BP), triglyceride, total cholesterol, high density lipoprotein cholesterol, creatinine, albumin and hemoglobin. RESULTS: The homocysteine levels was 10.5+/-5.9micromol/L in males, 7.3+/-2.6micromol/L in female. Thus it was significantly higher in males (P <0.001). After adjusting for variables that affect the homocysteine, the subjects over the age of 54 showed 10.7micromol/L (9.5, 12.0, 95% Confidence Interval), which was significantly (P=0.002) higher than the below the age of 38 groups 8.5micromol/L (7.8, 9.2, 95% CI). Non-smoking group showed 8.6micromol/L (8.4, 8.9, 95% CI), while over 28 pack-year group showed 9.6micromol/ L (9.2, 10.0, 95% CI), which was significantly (P <0.000) higher than the non-smoking groups. For the group with systolic BP over 132mmHg, it was 9.3micromol/L (8.8, 9.5, 95% CI). This was significantly (P=0.004) higher than 8.7micromol/L (8.4, 9.0, 95% CI) in the group whose systolic BP was less than 108 mmHg. The homocysteine was 10.4micromol/L (10.1, 11.7, 95% CI) for the group with creatinine over 1.0 mg/dL, which was significantly (P <0.000) higher than 7.9micromol/L (7.6, 8.2, 95% CI) in the group whose creatinine was less than 0.8 mg/dL. CONCLUSION: After adjusting for variables that affect the homocysteine, significant difference in its values was found between males and females. The homocysteine was significantly increased in the group whose age, systolic BP, amount of smoking, and creatinine were higher.

A Case of Bartter Syndrome with Muscle Weakness and Short Stature

Bartter syndrome is a rare disorder characterized by the association of hypokalemic hypochloremic metabolic alkalosis, hyperreninemia, hyperaldosteronemia, short stature and nephrocalcinosis. This disorder presents with hyperplasia of juxtaglomerular apparatus on renal biopsy. We experienced a case of late-onset Bartter syndrome with nephrocalcinosis in a 9-year-old boy, whose chief pictures were muscle weakness, short stature, persistent sterile pyuria and microscopic hematuria. We report this case with a brief review of related literatures.