Natural methoxyphenol compounds: Antimicrobial activity against foodborne pathogens and food spoilage bacteria, and role in antioxidant processes

The antibacterial and antioxidant activities of three methoxyphenol phytometabolites, eugenol, capsaicin, and vanillin, were determined. The in vitro antimicrobial potential was tested on three common foodborne pathogens (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus) and three food spoilage bacteria (Shewanella putrefaciens, Brochothrix thermosphacta, and Lactobacillus plantarum). The antioxidant assays were carried out for studying the free radical scavenging capacity and the anti-lipoperoxidant activity. The results showed that eugenol and capsaicin were the most active against both pathogens and spoilage bacteria. S. aureus was one of the most affected strains (median concentration of growth inhibition: IC50 eugenol = 0.75 mM; IC50 capsaicin = 0.68 mM; IC50 vanillin = 1.38 mM). All phytochemicals slightly inhibited the growth of L. plantarum. Eugenol was the most active molecule in the antioxidant assays. Only in the oxygen radical absorbing capacity (ORAC) test did vanillin show an antioxidant activity comparable to eugenol (eugenol ORAC value = 2.12 ± 0.08; vanillin ORAC value = 1.81 ± 0.19). This study, comparing the antimicrobial and antioxidant activities of three guaiacol derivatives, enhances their use in future applications as food additives for contrasting both common pathogens and spoilage bacteria and for improving the shelf life of preserved food

Primary Hyperparathyroidism Patients with Positive Preoperative Sestamibi Scan and Negative Ultrasound Are More Likely to Have Posteriorly Located Upper Gland Adenomas (PLUGs)

BackgroundStandard preoperative imaging for primary hyperparathyroidism usually includes sestamibi scanning (MIBI) and ultrasound (US). In a subset of patients with a positive MIBI and a negative US, we hypothesize that the parathyroid adenomas are more likely to be located posteriorly in the neck, where anatomically they are more difficult to detect by US.MethodsWe retrospectively reviewed the records of 661 patients treated for primary hyperparathyroidism between 2004 and 2009 at a tertiary referral center. We included patients who for their first operation had a MIBI that localized a single lesion in the neck and an US that found no parathyroid adenoma. We excluded patients with persistent or recurrent hyperparathyroidism, and patients with MIBIs that were negative, that had more than one positive focus, or that had foci outside of the neck. Sixty-six cases were included in the final analysis.ResultsA total of 54 patients (83%) had a single adenoma, 4 (6%) had double adenomas, and 7 (11%) had hyperplasia. Thirty-three patients (51%) had a single upper gland adenoma; 19 of these (58%) were posteriorly located upper gland adenomas (PLUGs). PLUGs occurred more often on the right side than on the left (P = 0.048, Fisher's test). PLUGs were also larger than other single adenomas (mean 1.85 vs. 1.48 cm, P = 0.021, t-test). Seventy-six percent of patients successfully underwent a unilateral or focused exploration. Six patients (9%) had persistent disease, which is double our group's overall average (4-5%).ConclusionsPrimary hyperparathyroid patients with preoperative positive MIBI and negative US are more likely to have PLUGs

Toxic impact of polystyrene microplastic particles in freshwater organisms

The ongoing COVID-19 pandemic is leading to an increase of the global production of plastics since the use of personal protective equipment (PPEs, i.e. gloves, gowns, masks, packaging items), has become mandatory to prevent the spread of the virus. Plastic breaks down into micro/nano particles due to physical or chemical or biological actions into environment. Due to small dimensions, ubiquitous and persistent nature, the plastic particles represent a significant threat to ecosystems and can entry into food chains. Among the plastic polymers used for PPEs, polystyrene is less studied regarding its eco-geno-toxicity. This study aims to investigate acute, chronic and subchronic effects of the microplastic polystyrene beads (PS-MP, size 1.0 μm) on three freshwater species, the alga Raphidocelis subcapitata, the rotifer Brachionus calyciflorus, the crustacean Ceriodaphnia dubia and the benthic ostracod Heterocypris incongruens. Furthermore, the potential genotoxicity and the ROS production due to the PS-MP were also determined in C. dubia. Results revealed that the acute effects occurred at concentrations of PS-MP in the order of dozens of mg/L in B. calyciflorus and C. dubia and hundreds of mg/L in H. incongruens. Regarding long-term toxicity, increasing chronic effects with EC50s in the order of units (C. dubia), hundreds (B. calyciflorus) and thousands (R. subcapitata) of μg/L were observed. Both for acute and chronic/sub chronic toxicity, daphnids were more sensitive to polystyrene than ostracods. Moreover, when C. dubia neonates were exposed to the PS-MP, alterations in genetic material as well as the production of ROS occurred, starting from concentrations in the order of units of μg/L, probably due to inflammatory responses. At last, the risk quotient (RQ) as a measure of risk posed by PS-MPs in freshwater environment, was calculated obtaining a value of 7.2, higher than the threshold value of 1

Comparative assessment of antimicrobial, antiradical and cytotoxic activities of cannabidiol and its propyl analogue cannabidivarin

Cannabidiol and cannabidivarin are phytocannabinoids produced by Cannabis indica and Cannabis sativa. Cannabidiol has been studied more extensively than its propyl analogue cannabidivarin. Therefore, we performed a battery of in vitro biological assays to compare the cytotoxic, antiradical and antibacterial activities of both cannabinoids. Potential mitochondrial metabolism alterations, DNA synthesis inhibition, and plasma membrane damage were studied by MTT assay, BrdU-ELISA and LDH assay of cancer and normal human cells exposed to cannabinoids. ABTS and DPPH assays were performed to observe the effects of the cannabinoids on free radicals. Microbial susceptibility tests were performed to study the activity of the cannabinoids in two bacterial species implicated in human infections, Escherichia coli and Staphylococcus aureus. The results showed that the cannabinoids induced medium levels of cytotoxicity in cancer and normal cells at concentrations ranging from 15.80 to 48.63 and from 31.89 to 151.70 µM, respectively, after 72 h of exposure. Cannabinoids did not exhibit a strong antioxidant capacity in scavenging ABTS or DPPH radicals. No evident differences were observed between the two cannabinoids in antimicrobial activity, except with respect to S. aureus, which showed greater susceptibility to cannabidiol than to cannabidivarin after 72 h of exposure

Polystyrene microplastic particles in combination with pesticides and antiviral drugs: Toxicity and genotoxicity in Ceriodaphnia dubia

Freshwater ecosystems are recognized as non-negligible sources of plastic contamination for the marine environment that is the final acceptor of 53 thousand tons of plastic per year. In this context, microplastic particles are well known to directly pose a great threat to freshwater organisms, they also indirectly affect the aquatic ecosystem by adsorbing and acting as a vector for the transport of other pollutants ( "Trojan horse effect "). Polystyrene is one of the most widely produced plastics on a global scale, and it is among the most abundant microplastic particles found in freshwaters. Nevertheless, to date few studies have focused on the eco-genotoxic effects on freshwater organisms caused by polystyrene microplastic particles (PS -MPs) in combination with other pollutants such as pharmaceuticals and pesticides. The aim of this study is to investigate chronic and sub-chronic effects of the microplastic polystyrene beads (PS-MP, 1.0 mu m) both as individual xenobiotic and in combination (binary/ternary mixtures) with the aciclo-guanosine antiviral drug acyclovir (AC), and the neonicotinoid broad-spectrum insecticide imidacloprid (IMD) in one of the most sensitive non-target organisms of the freshwater food chain: the cladoceran crustacean Cer-iodaphnia dubia. Considering that the individually selected xenobiotics have different modes of action and/or different biological sites, the Bliss independence was used as reference model for this research. Basically, when C. dubia neonates were exposed for 24 h to the mixtures during Comet assay, mostly an antagonistic genotoxic effect was observed. When neonates were exposed to the mixtures for 7 days, mostly an additive chronic toxic effect occurred at concentrations very close or even overlapping to the environmental ones ranging from units to tens of ng/L for PS-MPs, from tenths/hundredths to units of mu g/L for AC and from units to hundreds of mu g/L for IMD, revealing great environmental concern

Capsaicin in Hot Chili Peppers: In Vitro Evaluation of Its Antiradical, Antiproliferative and Apoptotic Activities

Capsaicin is a spicy capsaicinoid, produced as secondary metabolite by Capsicum fruits. This alkaloid has been used for years in folk medicine for its analgesic and antinflammatory properties although most data is referred to the raw fruit. In this study, the antiradical activity of the pure capsaicin has been studied using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays as well as its antiproliferative activity, using MTT assay, against two human tumour cell lines, the colorectal Caco-2 and the oesophageal OE19 cells. Furthermore, the antiproliferative activity observed on tumoral cells was compared with that of the human normal-like fibroblast cell line TelCOFS02MA. In addition, the apoptotic activity was evaluated using TUNEL assay. A higher radical scavenging activity was observed against ABTS radical cation than DPPH. Capsaicin showed also a higher cytotoxicity against cancer cells than normal-like cells with Selectivity index values greater than 2 at 72 h. Capsaicin induced apoptosis especially in OE19 cell line

Ultrasound-guided methylene blue dye injection for parathyroid localization in the reoperative neck.

BackgroundThe goal of this study was to review a single institution's experience using intraoperative ultrasound-guided (ioUSG) methylene blue dye injection for the localization and removal of enlarged parathyroid glands in patients with primary hyperparathyroidism and a history of previous neck surgery.MethodsWe performed a retrospective review of nine consecutive patients who underwent reoperative parathyroidectomy using ioUSG methylene blue dye injection.ResultsAll patients had successful resolution of their hyperparathyroidism, with at least a 50 % decrease in intraoperative parathyroid hormone level after resection. One patient had transient recurrent laryngeal nerve paresis. There were no permanent recurrent laryngeal nerve injuries or cases of permanent hypoparathyroidism.ConclusionsBlue dye injection is a safe and effective method of localizing diseased parathyroid glands in the reoperative neck