Development a high-throughput zebrafish embryo acute toxicity testing method based on OECD TG 236.

The Organization for Economic Co-operation and Development (OECD）Test Guideline (TG) 236 for zebrafish embryo acute toxicity testing was adopted for chemical toxicity assessment in 2013. Due to the increasing demand for prediction and evaluation of the acute toxicity using zebrafish embryos, we developed a method based on OECD 236 test guideline with the aim to improve the testing efficiency. We used 4-128 cell stage zebrafish embryos and performed an exposure assay in a 96-well microtiter plate, observing the lethality endpoints of embryos at 48-h postexposure. A total of 32 chemicals (two batches) were used in the comparison study. Our results indicated that the logarithmic LC50 (half lethal concentration) obtained by the modified method exhibited good correlation with that obtained by the OECD 236 testing method, and the R2 of the linear regression analysis was 0.9717 (0.9621 and 0.9936 for the two batches, respectively). Additionally, the intra- and inter-laboratory coefficient of variation (CVs) for the LC50 from the testing chemicals (17 chemicals in second batch) was less than 30%, except for CuSO4. Therefore, the developed method was less time-consuming and demonstrated a higher throughput for toxicity testing compared to the prior method. We argue the developed method could be used as an additional choice for high-throughput zebrafish embryo acute toxicity test.

Metal bioavailability in ecological risk assessment of freshwater ecosystems: From science to environmental management.

Metal contamination in freshwater ecosystems is a global issue and metal discharges to aquatic environments are monitored in order to protect aquatic life and human health. Bioavailability is an important factor determining metal toxicity. In aquatic systems, metal bioavailability depends on local water and sediment characteristics, and therefore, the risks are site-specific. Environmental quality standards (EQS) are used to manage the risks of metals in aquatic environments. In the simplest form of EQSs, total concentrations of metals in water or sediment are compared against pre-set acceptable threshold levels. Now, however, the environmental administration bodies have stated the need to incorporate metal bioavailability assessment tools into environmental regulation. Scientific advances have been made in metal bioavailability assessment, including passive samplers and computational models, such as biotic ligand models (BLM). However, the cutting-edge methods tend to be too elaborate or laborious for standard environmental monitoring. We review the commonly used metal bioavailability assessment methods and introduce the latest scientific advances that might be applied to environmental management in the future. We present the current practices in environmental management in North America, Europe and China, highlighting the good practices and the needs for improvement. Environmental management has met these new challenges with varying degrees of success: the USA has implemented site-specific environmental risk assessment for water and sediment phases, and they have already implemented metal mixture toxicity evaluation. The European Union is promoting the use of bioavailability and BLMs in ecological risk assessment (ERA), but metal mixture toxicity and sediment phase are still mostly neglected. China has regulation only for total concentrations of metals in surface water. We conclude that there is a need for (1) Advanced and up-to-date guidelines and legislation, (2) New and simple scientific methods for assessing metal bioavailability and (3) Improvement of knowledge and skills of administrators.

Patients' self-perceived burden, caregivers' burden and quality of life for amyotrophic lateral sclerosis patients: a cross-sectional study.

AIMS AND OBJECTIVES: This study surveys the quality of life of amyotrophic lateral sclerosis patients and the factors associated with amyotrophic lateral sclerosis patients' self-perceived burden and their caregivers' burden. BACKGROUND: Burdens of patients with amyotrophic lateral sclerosis and their caregivers in Chinese population are largely unknown. DESIGN: A cross-sectional study was conducted among 81 pairs of amyotrophic lateral sclerosis patients and their caregivers. METHODS: Amyotrophic lateral sclerosis patients' self-perceived burden and caregivers' burden were assessed by the Self-Perceived Burden Scale and Zarit-Burden Interview, respectively. Quality of life of amyotrophic lateral sclerosis patients was measured using the World Health Organization Quality of Life-Bref. The amyotrophic lateral sclerosis Functional Rating Scale-Revised questionnaire was used to estimate patients' physical function. RESULTS: Both patients and caregivers reported a mild to moderate burden. The World Health Organization quality of life-Bref scores were decreased in respondents with lower amyotrophic lateral sclerosis Functional Rating Scale-Revised, higher Self-Perceived Burden Scale and higher Zarit-Burden Interview scores. Self-Perceived Burden Scale scores were associated with patients' knowledge of amyotrophic lateral sclerosis, respiratory function and female sex. Zarit-Burden Interview scores were associated with caregivers' age, patients' motor function and out-of-pocket payment. CONCLUSION: With increase in amyotrophic lateral sclerosis patients' self-perceived burden and caregivers' burden, quality of life of amyotrophic lateral sclerosis patients decreased. Female patients, who had known more about the disease, and those with severe respiratory dysfunction were subject to higher self-perceived burden. Older caregivers and caregivers of patients with severe motor dysfunction and more out-of-pocket payment experienced more care burdens. RELEVANCE TO CLINICAL PRACTICE: Our study suggests that paying more attention to female amyotrophic lateral sclerosis patients might benefit patients in China or other South-East Asian countries under the Confucian concept of ethics. There is an urgent demand to expand medical insurance coverage to cover amyotrophic lateral sclerosis in China and other developing countries. Long and adequate supports are needed for relieving caregiver's burden. To improve the quality of life of patients, relieving the patients' SBP and caregivers' burden is likely to be not only required, but also essential.

Assessment of a multiple biomarker panel for diagnosis of amyotrophic lateral sclerosis.

BACKGROUND: The aim of the study was to assess a panel of promising biomarkers for their ability to improve diagnosis of sporadic amyotrophic lateral sclerosis (ALS). METHODS: Forty patients with sporadic ALS and 40 controls with other neurological diseases were evaluated. Levels of phosphorylated neurofilament heavy chain (pNfH), S100-ß, cystatin C, and chitotriosidase (CHIT) in cerebrospinal fluid were assayed using two-site solid-phase sandwich ELISA. RESULTS: Patients with sporadic ALS showed higher levels of pNfH and CHIT than controls, but lower levels of cystatin C. Multivariate logistic regression that adjusted for patient age and sex identified significant associations between sporadic ALS and levels of pNfH, CHIT and cystatin C. Levels of pNfH correlated positively with rate of progression and decline based on the Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised. Based on receiver operating curve analysis, a pNfH cut-off of 437 ng/L discriminated patients from controls with a sensitivity of 97.3 % and specificity of 83.8 %. A CHIT cut-off of 1593.779 ng/L discriminated patients from controls with a sensitivity of 83.8 % and specificity of 81.1 %. Combining the two biomarkers gave a sensitivity of 83.8 % and specificity of 91.9 %. CONCLUSIONS: Levels of pNfH in cerebrospinal fluid may be a reliable biomarker for diagnosing ALS, and combining this biomarker with levels of CHIT may improve diagnostic accuracy.

Assessment of TREM2 rs75932628 association with amyotrophic lateral sclerosis in a Chinese population.

Although, rs75932628 in triggering receptor expressed on myeloid cells 2 (TREM2) was shown to increase the risk for Alzheimer's disease, there is no agreement on the association between this variant and the risk for amyotrophic lateral sclerosis (ALS). We conducted a large-sample study to investigate if this variant is associated with ALS in a Chinese population. A total of 868 sporadic ALS (SALS) and 869 healthy controls were included. All cases were genotyped for the single nucleotide polymorphisms (SNP) using Sequenom iPLEX Assay technology. The rs75932628-T variant of the TREM2 gene was not identified in SALS patients and controls. It is unlikely to play a role in the pathogenesis of ALS in Chinese patients with SALS.

Assessment of TREM2 rs75932628 association with Parkinson's disease and multiple system atrophy in a Chinese population.

Although rs75932628 in triggering receptor expressed on myeloid cells 2 (TREM2) was shown to increase the risk for Alzheimer's disease, there is no agreement on the association between this variant and the risk for Parkinson's disease (PD). Considering the overlapping of clinical manifestation and pathologic characteristics of PD and multiple system atrophy (MSA), we conducted a large-sample study to investigate the associations between this variant and these two neurodegenerative diseases in a Chinese population. A total of 1216 PD, 406 MSA patients, and 869 healthy controls were included. All cases were genotyped for the Single Nucleotide Polymorphisms (SNP) using Sequenom iPLEX Assay technology. The rs75932628-T variant of the TREM2 gene was not identified in PD patients and controls. The genotype frequency of rs75932628-T SNP in MSA patients was 0.25% (1/406). However, no significant correlation was identified between this variant and the risk for MSA. TREM2 rs75932628 is unlikely to play a major role in the pathogenesis of these neurodegenerative diseases. Our findings argue against a generalized immune dysfunction triggered by the variant in the TREM2 gene.