A comprehensive HRMS methodology using LC-(ESI)-/GC-(APCI)-QTOF MS complementary platforms for wide-scope target screening of >750 pesticides in olive oil.

This study presents the development and validation of a comprehensive high-resolution mass spectrometry (HRMS) methodology for the detection of 771 pesticides in olive oil, using liquid chromatography with electrospray ionization, operating in positive and negative mode, and gas chromatography with atmospheric-pressure chemical ionization in positive mode, both coupled to quadrupole-time-of-flight mass spectrometry (LC-(ESI)-/GC-(APCI)-QTOF MS). Special reference is made to the post-acquisition evaluation step, in which all LC/GC-HRMS analytical evidence (i.e. mass accuracy, retention time, isotopic pattern, MS/MS fragmentation) is taken into account in order to successfully identify the compounds. The sample preparation of the method involves a QuEChERS-based protocol, common for both techniques, differentiated only on the reconstitution step, making the method highly applicable in routine analysis. A smart evaluation of method's performance was carried out, with 65 representative analytes comprising the validation set. The method was validated in terms of linearity, accuracy, matrix effect and precision, while the limits of detection and quantification of the method were estimated. Finally, twenty Greek olive oil samples were analysed in both analytical platforms and the findings included the pesticides lambda-cyhalothrin, chlorpyrifos, phosphamidon, pirimiphos-methyl and esprocarb at low ng g-1 level.

SARS-CoV-2 wastewater surveillance data can predict hospitalizations and ICU admissions.

We measured SARS-CoV-2 RNA load in raw wastewater in Attica, Greece, by RT-qPCR for the environmental surveillance of COVID-19 for 6 months. The lag between RNA load and pandemic indicators (COVID-19 hospital and intensive care unit (ICU) admissions) was calculated using a grid search. Our results showed that RNA load in raw wastewater is a leading indicator of positive COVID-19 cases, new hospitalization and admission into ICUs by 5, 8 and 9 days, respectively. Modelling techniques based on distributed/fixed lag modelling, linear regression and artificial neural networks were utilized to build relationships between SARS-CoV-2 RNA load in wastewater and pandemic health indicators. SARS-CoV-2 mutation analysis in wastewater during the third pandemic wave revealed that the alpha-variant was dominant. Our results demonstrate that clinical and environmental surveillance data can be combined to create robust models to study the on-going COVID-19 infection dynamics and provide an early warning for increased hospital admissions.

Spinal cord edema with contrast enhancement mimicking intramedullary tumor in patient with cervical myelopathy: A case report and a brief literature review.

BACKGROUND: Cervical myelopathy (CM) is a clinical diagnosis that may be associated with hyperintense areas on T2-weighted magnetic resonance imaging (MRI) scan. The use of contrast enhancement in such areas to differentiate between neoplastic and degenerative disease has rarely been described. CASE DESCRIPTION: We present a 41-year-old female with a 5-month course of progressive CM. The cervical MRI revealed spinal cord swelling, stenosis, and a hyperintense signal at the C5-C6 and C5-C7 levels. Both the neurologic and radiologic examinations were consistent with an intramedullary cervical cord tumor. To decompress the spinal canal, an anterior cervical discectomy and fusion was performed from C5 to C7 level. This resulted in immediate and significant improvement of the myelopathy. Postoperatively, over 1.5 years, the hyperintense, enhancing intramedullary lesion gradually regressed on multiple postoperative MRI scans. CONCLUSION: Spinal cord edema is occasionally seen on MR studies of the cervical spine in patients with degenerative CM. Contrast-enhanced MR studies may help differentiate hyperintense cord signals due to edema vs. atypical intramedullary tumors. Routine successive postoperative MRI evaluations are crucial to confirm the diagnosis of degenerative vs. neoplastic disease.