Quantification Of Metabolic Activity Research Articles

ID: 218555 Feasibility of 18FDG-PET-CT assessment of Multifidus Activity and Radiomics based Heterogeneity analysis During Restorative Neurostimulation

Restorative neurostimulation for chronic mechanical low back pain relies on stimulation of the L2 medial branch of the dorsal ramus to elicit episodic tetanic contractions of the lumbar multifidus muscle in order to restore neuromuscular control of the lumbar spine. Quantification of metabolic activity, heterogeneity using PET uptake measurements and radiomic based texture analysis on 18F FDG-PET/CT provide a unique opportunity to visualize and quantify changes in the CNS and muscles in response to restorative neurostimulation therapy.

Oral Dysbiosis Exacerbates Candida parapsilosis Sensu Stricto Biofilm Production via Up-Regulation of the CPH2 Biofilm Master Gene

Introduction: Candida parapsilosis sensu stricto is the second to third most frequent cause of candidemia. Studies place this yeast as a frequent colonizer of niches of the oral cavity, predominantly in pathological conditions. We hypothesize that a buccal environment in dysbiosis enhances the virulence of C. parapsilosis sensu stricto. Objective: To evaluate the phenotype and molecular level of the production of biofilm in oral isolates of Candida parapsilosis sensu stricto and correlate the results with the clinical origin (dysbiosis versus eubiosis). Materials and Methods: The biofilm-forming ability was compared in 50 oral isolates of Candida parapsilosis sensu stricto obtained from patients with and without oral dysbiosis; by quantification of metabolic activity. The results were corroborated by confocal fluorescence microscopy, and correlated with the transcriptional activity of CPH2, by RT-qPCR. The data were analysed by Excel 2010, and InfoStat 2018, with a 95% confidence interval. Results: The metabolic activity in biofilm was significantly higher in oral dysbiosis relative to control (p = 0.0025). Basal expression of CPH2 increased 2.8 times more in oral dysbiosis related to the control condition and showed no significant differences with pathogenic isolates of this same yeast, derived from onychomycosis lesions. Conclusion: The oral cavity in dysbiosis increases the virulence of C. parapsilosis sensu stricto due to possible changes in epigenetic marks. This finding suggests that the oral cavity in dysbiosis may be an alternative route to the skin in the epidemiology of nosocomial candidemia.

Capsaicin from chili ( Capsicum spp.) inhibits vascular smooth muscle cell proliferation

Accelerated vascular smooth muscle cell (VSMC) proliferation is implied in cardiovascular disease and significantly contributes to vessel lumen reduction following surgical interventions such as percutaneous transluminal coronary angioplasty or bypass surgery. Therefore, identification and characterization of compounds and mechanisms able to counteract VSMC proliferation is of potential therapeutic relevance. This work reveals the anti-proliferative effect of the natural product capsaicin from Capsicum spp. by quantification of metabolic activity and DNA synthesis in activated VSMC. The observed in vitro activity profile of capsaicin warrants further research on its mechanism of action and potential for therapeutic application.

Capsaicin from chili ( Capsicum spp.) inhibits vascular smooth muscle cell proliferation.

Accelerated vascular smooth muscle cell (VSMC) proliferation is implied in cardiovascular disease and significantly contributes to vessel lumen reduction following surgical interventions such as percutaneous transluminal coronary angioplasty or bypass surgery. Therefore, identification and characterization of compounds and mechanisms able to counteract VSMC proliferation is of potential therapeutic relevance. This work reveals the anti-proliferative effect of the natural product capsaicin from Capsicum spp. by quantification of metabolic activity and DNA synthesis in activated VSMC. The observed in vitro activity profile of capsaicin warrants further research on its mechanism of action and potential for therapeutic application.

The activity of ferulic and gallic acids in biofilm prevention and control of pathogenic bacteria

The activity of two phenolic acids, gallic acid (GA) and ferulic acid (FA) at 1000 μg ml−1, was evaluated on the prevention and control of biofilms formed by Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. In addition, the effect of the two phenolic acids was tested on planktonic cell susceptibility, bacterial motility and adhesion. Biofilm prevention and control were tested using a microtiter plate assay and the effect of the phenolic acids was assessed on biofilm mass (crystal violet staining) and on the quantification of metabolic activity (alamar blue assay). The minimum bactericidal concentration for P. aeruginosa was 500 μg ml−1 (for both phenolic acids), whilst for E. coli it was 2500 μg ml−1 (FA) and 5000 μg ml−1 (GA), for L. monocytogenes it was >5000 μg ml−1 (for both phenolic acids), and for S. aureus it was 5000 μg ml−1 (FA) and >5000 μg ml−1 (GA). GA caused total inhibition of swimming (L. monocytogenes) and swarming (L. monocytogenes and E. coli) motilities. FA caused total inhibition of swimming (L. monocytogenes) and swarming (L. monocytogenes and E. coli) motilities. Colony spreading of S. aureus was completely inhibited by FA. The interference of GA and FA with bacterial adhesion was evaluated by the determination of the free energy of adhesion. Adhesion was less favorable when the bacteria were exposed to GA (P. aeruginosa, S. aureus and L. monocytogenes) and FA (P. aeruginosa and S. aureus). Both phenolics had preventive action on biofilm formation and showed a higher potential to reduce the mass of biofilms formed by the Gram-negative bacteria. GA and FA promoted reductions in biofilm activity >70% for all the biofilms tested. The two phenolic acids demonstrated the potential to inhibit bacterial motility and to prevent and control biofilms of four important human pathogenic bacteria. This study also emphasizes the potential of phytochemicals as an emergent source of biofilm control products.

PET-CT in the staging and treatment of non-small-cell lung cancer

Positron emission tomography with 2-((18)F)-fluoro- 2-deoxy-D-glucose (FDG-PET) is a metabolic imaging technique. FDG-PET is more accurate than CT for the evaluation of mediastinal involvement in patients with nonsmall- cell lung cancer, offering a high negative predictive value. It can detect occult metastases in 11% of patients, although the etiology of the extrathoracic isolated uptakes needs confirmation. Theoretically, FDG-PET can influence the planning volume for radiotherapy, primarily in patients with atelectasis. Quantification of metabolic activity using FDG-PET is influenced by the size of the lesion, glucose levels and the time elapsed since the isotope injection. More clinical trials are required to standardize the methods for performing PET, assess its use as a prognostic factor and for the evaluation of treatment response.