A Pilot Study Examining the Use of Ultrasound to Measure Intravascular Volume Status in Agricultural Workers in a Field-Based Research Setting.

OBJECTIVE: The aim of this pilot study was to explore if internal jugular vein (IJV) ultrasound studies on agricultural workers in a field-based research setting could assess volume status during a hydration intervention. METHODS: We performed pre- and post-work shift IJV ultrasound images on 30 agricultural workers. The IJV collapsibility index values were <39% (euvolemic) or ≥39% (hypovolemic). RESULTS: Of the water group, 13% (2/15) had an IJV collapsibility index ≥39%, and this increased to 19% (3/16) by the end of the work shifts. The electrolyte group did not have any workers start the work shift with an IJV collapsibility index ≥39%; however, at the postshift assessment, 15% (2/13) were hypovolemic. CONCLUSION: Internal jugular vein ultrasounds may have the potential to be a useful tool to determine volume status in field-based research settings. Further investigation is needed to confirm these findings.

Immobilization of pectinesterase in genipin-crosslinked chitosan membrane for low methoxyl pectin production.

In this study, an environmentally friendly method for preparation of chitosan crosslinked membranes with different genipin concentrations (0, 125, 250, and 500 mg/L) was developed. Genipin-crosslinked chitosan membranes were used for the immobilization of fungal pectinesterase (PE). PE was efficiently immobilized in chitosan membranes and used for modification of high-methoxylated pectins into low-methoxylated pectins. The charge density (ζ-potential), infrared spectroscopy (FTIR), and ion-exchange chromatography (IEC) revealed the modification of pectin for immobilized PE in genipin-crosslinked chitosan membrane. The ζ-potential results indicated a decrease of -5.2 mV in the pectin control solution, whereas using the PE immobilized in chitosan and genipin-chitosan membranes, the obtained values were -30.45 mV and -36.38 mV, respectively. Genipin-crosslinked chitosan membrane jointly with the immobilized PE represents an eco-friendly support to prepare tailor-made low-methoxylated lime pectin.