Evidence of small microplastics (<100 μm) ingestion by Pacific oysters (Crassostrea gigas): A novel method of extraction, purification, and analysis using Micro-FTIR

Microplastics (MPs) are present in fresh, brackish, or marine waters. Micro- and macroinvertebrates can mistake MPs or small microplastics (SMPs, <100 μm) to be food particles and easily ingest them according to the size of their mouthparts. SMPs may then block the passage of food through the intestinal tract (i.e. hepatopancreas), accumulate within the organism, and enter the food web. Pacific oysters (Crassostrea gigas) are allochthonous filter-feeding bivalve mollusks, which have been introduced in coastal seas around the world in both natural banks and farms. Considering their economic and ecological value, these bivalves have been chosen as a model to study the ingestion of SMPs. A novel method for the extraction and purification of SMPs in bivalves was developed. Quantification and simultaneous polymer identification of SMPs using Micro-FTIR (Fourier Transform Infrared Spectroscopy) were performed, with a limit of detection for the particle size of 5 μm.

Propriospinal myoclonus: a neurophysiologic analysis

We are reporting a neurophysiologic analysis of two patients presenting with thoracoabdominal spontaneous muscle jerks. Polymyographic recordings showed myoclonic bursts with onset in the upper rectus abdominis or lower intercostal muscles followed by rostral propagation to the upper intercostal and caudal propagation to the abdominal muscles by slowly conducting pathways. Jerk-locked back-averaging did not show time-locked cortical or premovement potentials. Peroneal somatosensory evoked response, C-reflex, and intercostal nerve conduction were normal. These findings suggest a generator for the myoclonus in the midthoracic region of the spinal cord with up and down propagation by slowly conducting pathways, such as propriospinal fibers. This type of spinal myoclonus may thus be termed "propriospinal myoclonus," as suggested by Brown et al.