139 research outputs found

    Factors controlling atmospheric DMS and its oxidation products (MSA and nssSO(4)(2-)) in the aerosol at Terra Nova Bay, Antarctica

    Get PDF
    This paper presents the results of simultaneous high time-resolution measurements of biogenic aerosol (methane sulfonic acid (MSA), non-sea salt sulfate nssSO(4)(2-)) with its gaseous precursor dimethylsulfide (DMS), performed at the Italian coastal base Mario Zucchelli Station (MZS) in Terra Nova Bay (MZS) during two summer campaigns (2018-2019 and 2019-2020). Data on atmospheric DMS concentration are scarce, especially in Antarctica. The DMS maximum at MZS occurs in December, one month earlier than at other Antarctic stations. The maximum of DMS concentration is connected with the phytoplanktonic senescent phase following the bloom of Phaeocystis antarctica that occurs in the polynya when sea ice opens up. The second plankton bloom occurs in January and, despite the high dimethylsufoniopropionate (DMSP) concentration in seawater, atmospheric DMS remains low, probably due to its fast biological turnover in seawater in this period. The intensity and timing of the DMS evolution during the two years suggest that only the portion of the polynya close to the sampling site produces a discernible effect on the measured DMS. The closeness to the DMS source area and the occurrence of air masses containing DMS and freshly formed oxidation products allow us to study the kinetic of biogenic aerosol formation and the reliable derivation of the branch ratio between MSA and nssSO(4)(2-) from DMS oxidation that is estimated to be 0.84 +/- 0.06. Conversely, for aged air masses with low DMS content, an enrichment of nssSO(4)(2-) with respect to MSA, is observed. We estimate that the mean contribution of freshly formed biogenic aerosol to PM10 is 17 % with a maximum of 56 %. The high contribution of biogenic aerosol to the total PM10 mass in summer in this area highlights the dominant role of the polynya on biogenic aerosol formation. Finally, due to the regional and year-to-year variability of DMS and related biogenic aerosol formation, we stress the need for long-term measurements of seawater and atmospheric DMS and biogenic aerosol along the Antarctic coast and in the Southern Ocean

    Incidental Thyroid Carcinoma by FDG-PET/CT: A Study of Clinicopathological Characteristics

    Get PDF
    BACKGROUND: The rising incidence of incidental thyroid carcinoma (ITC) detected during fluoro-2-deoxy-D: -glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) scanning poses a challenge to clinicians. The present study aims to critically evaluate the clinicopathological characteristics of ITC detected by FDG-PET/CT. METHODS: Among the 557 patients managed at our institution, 40 (7.2%) patients were identified as having ITC. Of these, 22 patients had their tumor detected by FDG-PET/CT (PET group) and 11 by ultrasonography (USG group). Additional bedside ultrasonography +/- fine-needle aspiration (FNA) was done in all patients at their clinic visit. The clinicopathological characteristics were compared between the PET and USG groups. RESULTS: The PET group had significantly more patients with history of nonthyroidal malignancy (P < 0.001). Papillary carcinoma was the most common histological type in both groups. Despite having similar histological and prognostic features including tumor size, tumor multifocality, capsular invasion, extrathyroidal extension, and lymph node metastases, tumor bilaterality (or presence of contralateral tumor focus) was significantly more frequent in the PET than the USG group (P = 0.04). The tumors were also more advanced by the tumor-node-metastasis (TNM) staging system in the PET group (P = 0.021). None of the contralateral tumor foci were evident preoperatively. One patient in the USG group developed metastatic thyroid carcinoma in neck lymph nodes 28 months after thyroid resection. CONCLUSION: ITC by FDG-PET/CT had higher incidence of tumor bilaterality than those detected by ultrasonography. Total thyroidectomy should be considered for ITC detected by FDG-PET/CT even for tumor size <10 mm.published_or_final_versionSpringer Open Choice, 31 May 201

    Psychological stress in adolescent and adult mice increases neuroinflammation and attenuates the response to LPS challenge

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>There is ample evidence that psychological stress adversely affects many diseases. Recent evidence has shown that intense stressors can increase inflammation within the brain, a known mediator of many diseases. However, long-term outcomes of chronic psychological stressors that elicit a neuroinflammatory response remain unknown.</p> <p>Methods</p> <p>To address this, we have modified previously described models of rat/mouse predatory stress (PS) to increase the intensity of the interaction. We postulated that these modifications would enhance the predator-prey experience and increase neuroinflammation and behavioral dysfunction in prey animals. In addition, another group of mice were subjected to a modified version of chronic unpredictable stress (CUS), an often-used model of chronic stress that utilizes a combination of stressors that include physical, psychological, chemical, and other. The CUS model has been shown to exacerbate a number of inflammatory-related diseases via an unknown mechanism. Using these two models we sought to determine: 1) whether chronic PS or CUS modulated the inflammatory response as a proposed mechanism by which behavioral deficits might be mediated, and 2) whether chronic exposure to a pure psychological stressor (PS) leads to deficits similar to those produced by a CUS model containing psychological and physical stressors. Finally, to determine whether acute PS has neuroinflammatory consequences, adult mice were examined at various time-points after PS for changes in inflammation.</p> <p>Results</p> <p>Adolescent mice subjected to chronic PS had increased basal expression of inflammation within the midbrain. CUS and chronic PS mice also had an impaired inflammatory response to a subsequent lipopolysaccharide challenge and PS mice displayed increased anxiety- and depressive-like behaviors following chronic stress. Finally, adult mice subjected to acute predatory stress had increased gene expression of inflammatory factors.</p> <p>Conclusion</p> <p>Our results demonstrate that predatory stress, an ethologically relevant stressor, can elicit changes in neuroinflammation and behavior. The predatory stress model may be useful in elucidating mechanisms by which psychological stress modulates diseases with an inflammatory component.</p

    The future prospects of Lithuanian family physicians: a 10-year forecasting study

    Get PDF
    BACKGROUND: When health care reform was started in 1991, the physician workforce in Lithuania was dominated by specialists, and the specialty of family physician (FP) did not exist at all. During fifteen years of Lithuania's independence this specialty evolved rapidly and over 1,900 FPs were trained or retrained. Since 2003, the Lithuanian health care sector has undergone restructuring to optimize the network of health care institutions as well as the delivery of services; specific attention has been paid to the development of services provided by FPs, with more health care services shifted from the hospital level to the primary health care level. In this paper we analyze if an adequate workforce of FPs will be available in the future to take over new emerging tasks. METHODS: A computer spreadsheet simulation model was used to project the supply of FPs in 2006–2015. The supply was projected according to three scenarios, which took into account different rates of retirement, migration and drop out from training. In addition different population projections and enrolment numbers in residency programs were also considered. Three requirement scenarios were made using different approaches. In the first scenario we used the requirement estimated by a panel of experts using the Delphi technique. The second scenario was based on the number of visits to FPs in 2003 and took into account the goal to increase the number of visits. The third scenario was based on the determination that one FP should serve no more than 2,000 inhabitants. The three scenarios for the projection of supply were compared with the three requirement scenarios. RESULTS: The supply of family physicians will be higher in 2015 compared to 2005 according to all projection scenarios. The largest differences in the supply scenarios were caused by different migration rates, enrolment numbers to training programs and the retirement age. The second supply scenario, which took into account 1.1% annual migration rate, stable enrolment to residency programs and later retirement, appears to be the most probable. The first requirement scenario, which was based on the opinion of well-informed key experts in the field, appears to be the best reflection of FP requirements; however none of the supply scenarios considered would satisfy these requirements. CONCLUSION: Despite the rapid expansion of the FP workforce during the last fifteen years, ten-year forecasts of supply and requirement indicate that the number of FPs in 2015 will not be sufficient. The annual enrolment in residency training programs should be increased by at least 20% for the next three years. Accurate year-by-year monitoring of the workforce is crucial in order to prevent future shortages and to maintain the desired family physician workforce

    Metabolic constituents of grapevine and grape-derived products

    Get PDF
    The numerous uses of the grapevine fruit, especially for wine and beverages, have made it one of the most important plants worldwide. The phytochemistry of grapevine is rich in a wide range of compounds. Many of them are renowned for their numerous medicinal uses. The production of grapevine metabolites is highly conditioned by many factors like environment or pathogen attack. Some grapevine phytoalexins have gained a great deal of attention due to their antimicrobial activities, being also involved in the induction of resistance in grapevine against those pathogens. Meanwhile grapevine biotechnology is still evolving, thanks to the technological advance of modern science, and biotechnologists are making huge efforts to produce grapevine cultivars of desired characteristics. In this paper, important metabolites from grapevine and grape derived products like wine will be reviewed with their health promoting effects and their role against certain stress factors in grapevine physiology

    Host restriction factors in retroviral infection: promises in virus-host interaction

    Get PDF
    corecore