More than 50 years have passed since Haszeldine reported the first addition of a trifluoromethyl radical to an allene; in the intervening years, both the chemistry of allenes and the reactivity of ...single-electron species have become topics of intense interest. In this Review, we provide an overview of the fundamentals of radical additions to allenes and highlight the emergence of theoretical and experimental evidence that reveals unique reactivity patterns for radical additions to allenes as compared with other unsaturated compounds. Factors capable of exerting control over the chemo-, regio-, and stereoselectivities of the attack of carbon- and heteroatom-based radicals at each of the three potential reactive sites in an allene substrate are described. These include reaction conditions, the nature of the attacking radical, the substitution pattern of the allene, and the length of the linker between the radical center and the proximal allene carbon in the substrate. Cycloaddition reactions between allenes and partners containing π-bonds, which are likely to proceed through radical pathways, are presented to highlight their ability to rapidly access complex polycyclic scaffolds. Finally, the synthetic utility of the products arising from these chemistries is described, including their applications to the construction of complex molecules.
COI DNA barcoding is increasingly recognized as a significant new tool for the recognition and identification of animal species. Here, publicly available barcode data are compiled and analysed for ...birds (657 species) and fishes (1088 species). The proportion of species that cannot be barcode-distinguished by this marker is approximately 6.4% for birds and 2.1-2.5% for fishes. At all hierarchical taxonomic levels (species, genera, family, order, class), fish show greater mean COI divergence than birds. If two samples are barcode-identical, then for both birds and fishes, the probability that they are from the same species is 98-99%. The probability of conspecificity rapidly drops as divergence increases. At 2% COI divergence, this probability approximates to 1% for birds and 3% for fishes. The apparent difference between birds and fishes might partially reflect currently unrecognized cryptic species complexes in the latter. These probability estimates derive from pooled samples of birds and pooled samples of fishes, and will not apply in all situations. Recently evolved species complexes will have higher proportions of species that are barcode-identical. As barcode data accumulate, more refined statistical analyses will become possible.
A large discrepancy exists between the dire impacts that most natural scientists project we could face from climate change and the modest estimates of damages calculated by mainstream economists. ...Economic assessments of climate change risks are intended to be comprehensive, covering the full range of physical impacts and their associated market and non-market costs, considering the greater vulnerability of poor people and the challenges of adaptation. Available estimates still fall significantly short of this goal, but alternative approaches that have been proposed attempt to address these gaps. This review seeks to provide a common basis for natural scientists, social scientists, and modellers to understand the research challenges involved in evaluating the economic risks of climate change. Focusing on the estimation processes embedded in economic integrated assessment models and the concerns raised in the literature, we summarise the frontiers of research relevant to improving quantitative damage estimates, representing the full complexity of the associated systems, and evaluating the impact of the various economic assumptions used to manage this complexity.
The focus of this work is the role milk polar lipids play in affecting gut permeability, systemic inflammation, and lipid metabolism during acute and chronic inflammation induced by a single ...subcutaneous injection of lipopolysaccharide. Three groups of C57BL/6J mice were fed: modified AIN-93G diet with moderate level of fat (CO); CO with milk gangliosides (GG); CO with milk phospholipids (MPL). The MPL did not prevent a gut permeability increase upon LPS stress but increased the expression of tight junction proteins zonula occludens-1 and occludin in colon mucosa. The GG prevented the gut permeability increase upon LPS stress. The MPL decreased absolute and relative liver mass and decreased hepatic gene expression of acetyl-CoA carboxylase 2 and 3-hydroxy-3-methylglutaryl-CoA reductase. The GG increased hepatic gene expression of acetyl-CoA acyltransferase 2. In conclusion, milk GG protected the intestinal barrier integrity but had little effect on systemic inflammation and lipid metabolism; milk MPL, conversely, had complex effects on gut permeability, did not affect systemic inflammation, and had beneficial effect on hepatic lipid metabolism.
IMPORTANCE: Synovitis is common and is associated with progression of structural characteristics of knee osteoarthritis. Intra-articular corticosteroids could reduce cartilage damage associated with ...synovitis but might have adverse effects on cartilage and periarticular bone. OBJECTIVE: To determine the effects of intra-articular injection of 40 mg of triamcinolone acetonide every 3 months on progression of cartilage loss and knee pain. DESIGN, SETTING, AND PARTICIPANTS: Two-year, randomized, placebo-controlled, double-blind trial of intra-articular triamcinolone vs saline for symptomatic knee osteoarthritis with ultrasonic features of synovitis in 140 patients. Mixed-effects regression models with a random intercept were used to analyze the longitudinal repeated outcome measures. Patients fulfilling the American College of Rheumatology criteria for symptomatic knee osteoarthritis, Kellgren-Lawrence grades 2 or 3, were enrolled at Tufts Medical Center beginning February 11, 2013; all patients completed the study by January 1, 2015. INTERVENTIONS: Intra-articular triamcinolone (n = 70) or saline (n = 70) every 12 weeks for 2 years. MAIN OUTCOMES AND MEASURES: Annual knee magnetic resonance imaging for quantitative evaluation of cartilage volume (minimal clinically important difference not yet defined), and Western Ontario and McMaster Universities Osteoarthritis index collected every 3 months (Likert pain subscale range, 0 no pain to 20 extreme pain; minimal clinically important improvement, 3.94). RESULTS: Among 140 randomized patients (mean age, 58 SD, 8 years, 75 women 54%), 119 (85%) completed the study. Intra-articular triamcinolone resulted in significantly greater cartilage volume loss than did saline for a mean change in index compartment cartilage thickness of −0.21 mm vs −0.10 mm (between-group difference, −0.11 mm; 95% CI, −0.20 to −0.03 mm); and no significant difference in pain (−1.2 vs −1.9; between-group difference, −0.6; 95% CI, −1.6 to 0.3). The saline group had 3 treatment-related adverse events compared with 5 in the triamcinolone group and had a small increase in hemoglobin A1c levels (between-group difference, −0.2%; 95% CI, −0.5% to −0.007%). CONCLUSIONS AND RELEVANCE: Among patients with symptomatic knee osteoarthritis, 2 years of intra-articular triamcinolone, compared with intra-articular saline, resulted in significantly greater cartilage volume loss and no significant difference in knee pain. These findings do not support this treatment for patients with symptomatic knee osteoarthritis. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01230424
The use of cryoablation, a minimally-invasive image-guided technique to target and kill cancer cells, continues to gain traction within the medical field and with patients. This includes the use of ...cryoablation for the treatment of small breast cancers and focal sites of metastatic disease. In comparison to open surgical approaches, length of hospital stay and recovery time are decreased with the use of cryoablation. Research studies have also found that cryoablation may actually enhance tumor susceptibility to immunotherapy agents. Immunotherapy enhances a person’s own immune system to identify and attack cancer cells. It is proposed that after cryoablation there is increased expression of tumor specific antigens which the body can recognize as foreign invaders and with the combination of immunotherapy, result in an even more robust and efficient attack on the cancer cells. In this review we aim to highlight some of the recent advances in cryoablation which support the potential for cryoablation to induce these tumor-specific immune responses and thus supporting the use of combining cryoablation and immunotherapy for the treatment of breast cancer.
Ultrasound-Guided Breast Cancer Cryoablation Ward, Robert C; Lourenco, Ana P; Mainiero, Martha B
American journal of roentgenology (1976),
09/2019, Letnik:
213, Številka:
3
Journal Article
Recenzirano
Percutaneous ultrasound-guided breast cryoablation is a minimally invasive technique that kills targeted tissue with extreme cold, requires only local anesthesia, and takes less than 45 minutes to ...complete.
We discuss the indications for breast cryoablation, the mechanism of cell death, and types of commercially available devices; illustrate procedural technique; and review expected follow-up imaging findings in treated primary breast cancer.
Mislabelling of seafood products has been documented in numerous countries for over three-quarters of a century. With a trend towards increased consumption of seafood, the informed consumer demands ...accurately labelled products that provide full disclosure of composition. DNA barcoding can be used to accurately identify a seafood product to species based on its genetic signature, and so provides a means to test the authenticity and accuracy of seafood labelling. This can be especially useful for products such as fillets which have few or no unambiguous identifying characters, and can easily be mislabelled. We investigated labelling accuracy in seafood retailers in Tasmania, Australia. Thirty-eight seafood products were obtained from seafood retailers, sequenced for the barcoding gene region cytochrome oxidase subunit 1(CO1), and subsequently identified to species level by querying GenBank and Barcode of Life Data Systems (BOLD) DNA sequence records. Results were compared with standard fish names (SFN) prescribed under the Australian Fish Names Standard (AFNS) and FishBase. Of the 38 samples, none were deemed to have been mislabelled under Australian regulation, although in some cases naming discrepancies and ambiguity may cause confusion for some consumers. Our work, while reflecting high standards in Tasmanian seafood, highlights the need for mandatory standard labelling across all seafood products so as to eliminate any possible misrepresentation.
•We investigated labelling accuracy in seafood retailers in Tasmania, Australia.•We examined thirty-eight seafood samples obtained anonymously from retailers.•Sequenced these for barcoding region CO1 and identified to species level by querying BOLD records.•Results compared with Standard Fish Names prescribed under the AFNS and FishBase.•No mislabelling observed under Australian regulation, suggesting high labelling standards.
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