Neuromuscular manifestations of lead poisoning in opium and herbal users in Iran

Iranian clinical practice guideline for amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegeneration involving motor neurons. The 3-5 years that patients have to live is marked by day-to-day loss of motor and sometimes cognitive abilities. Enormous amounts of healthcare services and resources are necessary to support patients and their caregivers during this relatively short but burdensome journey. Organization and management of these resources need to best meet patients' expectations and health system efficiency mandates. This can only occur in the setting of multidisciplinary ALS clinics which are known as the gold standard of ALS care worldwide. To introduce this standard to the care of Iranian ALS patients, which is an inevitable quality milestone, a national ALS clinical practice guideline is the necessary first step. The National ALS guideline will serve as the knowledge base for the development of local clinical pathways to guide patient journeys in multidisciplinary ALS clinics. To this end, we gathered a team of national neuromuscular experts as well as experts in related specialties necessary for delivering multidisciplinary care to ALS patients to develop the Iranian ALS clinical practice guideline. Clinical questions were prepared in the Patient, Intervention, Comparison, and Outcome (PICO) format to serve as a guide for the literature search. Considering the lack of adequate national/local studies at this time, a consensus-based approach was taken to evaluate the quality of the retrieved evidence and summarize recommendations.

Development and application of a high accuracy method for measuring Pb in blood

BACKGROUND

Lead (Pb) is an environmental pollutant, and human exposure is assessed by measuring blood Pb concentrations. Today, the use of Pb-based products is restricted, but the health effects of low Pb concentrations require investigation. For this, a high-accuracy method is needed. Here, we report a new inductively coupled plasma mass spectrometry (ICP-MS) method for quantifying Pb in blood.

METHODS

Blood samples and calibrators were gravimetrically spiked with bismuth as an internal standard, digested with ultrapure nitric acid, and diluted 100 times. The calibrators were made from high-purity reference materials supplied by the National Institute of Standards and Technology, and the sample concentration was measured using the calibration bracketing method. The analytical performance and application of the new method were investigated.

RESULTS

The method had good specificity and a negligible matrix effect. The intra- and inter-assay coefficients of variation (CVs) were <1.34 % and <1.88 %, respectively, and the total CV was <1.74 %. The range of recovery was 98.9 %-99.4 %. SRM955d, BCR-635, and BCR-636 were within the certified intervals, with mean relative bias values of 0.93 %, -0.13 %, and -0.56 %, respectively. The limit of quantification was 1.1 µg/l. The method was used to assign target values to external quality assessment samples and to assess routine methods, showing good results at high concentrations. However, at low concentrations, two laboratories did not pass.

CONCLUSIONS

This ICP-MS method is a simple, accurate method and can be a candidate reference method for blood Pb measurement. But more research will be needed to verify this.

Comparative efficacy of silibinin and nano-silibinin on lead poisoning in Male Wistar rats

Lead (Pb) is an environmental neurotoxin that can lead to toxicity. It has shown that tissues can be exposed to oxidative stress in lead poisoning. Since silymarin is a natural agent with antioxidant effects, this study aimed to investigate the antioxidant and chelation effects of silibinin and nano-silibinin on the oxidative stress status in lead-poisoned rats. Sixty male Wistar rats randomly divided into ten groups (n = 6). Control and Pb groups treated with or without silibinin and nano-silibinin for six days. Following measuring of weight and blood lead levels, biochemical antioxidant parameters evaluated. Finally, a histopathological examination of the liver performed. In this experiment, silibinin and more efficiently nano-silibinin prevented weight loss and blood lead level elevation induced by lead. Also, they increased the attenuated levels of superoxide dismutase (SOD) activity, catalase (CAT), total thiol molecules (TTM), glutathione (GSH), and total antioxidant capacity (TAC). Lead-induced elevation of lipid peroxidation products (MDA) and nitric oxide (NO) normalized to the standard level in silibinin and especially nano-silibinin groups. These data suggested that silibinin and especially nano-silibinin can decrease blood lead levels and prevent weight loss and oxidative stress in the lead-poisoned rat's model.