411 research outputs found

    Multiple double-exchange mechanism by Mn2+^{2+}-doping in manganite compounds

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    Double-exchange mechanisms in RE1−x_{1-x}AEx_{x}MnO3_{3} manganites (where RE is a trivalent rare-earth ion and AE is a divalent alkali-earth ion) relies on the strong exchange interaction between two Mn3+^{3+} and Mn4+^{4+} ions through interfiling oxygen 2p states. Nevertheless, the role of RE and AE ions has ever been considered "silent" with respect to the DE conducting mechanisms. Here we show that a new path for DE-mechanism is indeed possible by partially replacing the RE-AE elements by Mn2+^{2+}-ions, in La-deficient Lax_{x}MnO3−ή_{3-\delta} thin films. X-ray absorption spectroscopy demonstrated the relevant presence of Mn2+^{2+} ions, which is unambiguously proved to be substituted at La-site by Resonant Inelastic X-ray Scattering. Mn2+^{2+} is proved to be directly correlated to the enhanced magneto-transport properties because of an additional hopping mechanism trough interfiling Mn2+^{2+}-ions, theoretically confirmed by calculations within the effective single band model. The very idea to use Mn2+^{2+} both as a doping element and an ions electronically involved in the conduction mechanism, has never been foreseen, revealing a new phenomena in transport properties of manganites. More important, such a strategy might be also pursed in other strongly correlated materials.Comment: 6 pages, 5 figure

    Recurrent Ascending Colon Cancer Manifesting as Inferior Vena cava Thrombus

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    We report an extremely rare case of recurrent ascending colon cancer manifesting as inferior vena cava (IVC) thrombus. A 77-year-old woman previously diagnosed with ascending colon cancer underwent right hemicolectomy with lymph node dissection. Though the tumor invaded the retroperitoneum and involved the right ovarian artery and vein, curative operation was performed. The patient took 5-FU p.o. Two and a half years later, tumor thrombus in the IVC extending into the right atrium was incidentally found and diagnosed as recurrence of colon cancer by biopsy. RF-induced hyperthermia using 5-FU and CDDP i.v. was immediately performed, but she died after 6 months because of multiple liver and pulmonary metastases. In treating colon cancers invading the retroperitoneum, it should be recalled that some cases recur as tumor thrombus in the IVC and that close follow-up is therefore necessary

    Wider implications of video-assisted thoracic surgery versus open approach for lung metastasectomy

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    Lung metastasectomy is considered a safe and potentially curative procedure despite there is not a strong evidence that metastasectomy prolongs long-term survival in patients with lung metastases. Moreover, the debate is open regarding the best approach for lung metastasectomy, video-assisted thoracic surgery versus open approach. A systematic review of literature to clarify what is the best approach to prolong survival in patients with lung metastases was performed. Our study confirms that overall survival is equivalent for video-assisted thoracic surgery and thoracotomy, therefore the ‘gold standard’ surgical treatment for lung metastases remains a point of debate. The choice of the surgical approach still depends more on the single center or surgeon practice than on strong scientific evidence. A prospective randomized trial could clarify the question

    New Early Eocene mammalian fauna from western Patagonia, Argentina

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    Two new fossil mammal localities from the Paleogene of central-western Patagonia are preliminarily described as the basis for a new possible biochronological unit for the early Eocene of Patagonia, correlated as being between two conventional SALMAs, the Riochican (older) and the Vacan subage of the Casamayoran SALMA. The mammal-bearing strata belong to the Middle Chubut River Volcanic-Pyroclastic Complex (northwestern Chubut Province, Argentina), of Paleocene-Eocene age. This complex includes a variety of volcaniclastic, intrusive, pyroclastic, and extrusive rocks deposited after the K-T boundary. Geochronological data taken from nearby volcanic deposits that underlie and overlie the mammal-bearing levels indicate that both faunas are of late early Eocene age (Ypresian-Lutetian boundary). In addition to more than 50 species of mammals, including marsupials, ungulates, and xenarthrans, two lower molars are the oldest evidence of bats in South America. Paleobotanical and palynological evidence from inferred contemporary localities nearby indicate subtropical environments characterized by warm and probably moderately humid climate. Remarkably, this new fauna is tentatively correlated with Eocene mammals from the La Meseta Formation in the Antarctic Peninsula. We conclude that the two localities mentioned above are part of a possible new biochronological unit, but the formal proposal of a new SALMA awaits completion of taxonomic analysis of the materials reported upon here. If the La Meseta fauna is correlated biochronologically to western Patagonia, this also suggests a continental extension of the biogeographic Weddelian Province as far north as central-western Patagonia

    Contribution of pulmonary function tests (PFTs) to the diagnosis and follow up of connective tissue diseases

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    Introduction: Connective Tissue Diseases (CTDs) are systemic autoimmune conditions characterized by frequent lung involvement. This usually takes the form of Interstitial Lung Disease (ILD), but Obstructive Lung Disease (OLD) and Pulmonary Artery Hypertension (PAH) can also occur. Lung involvement is often severe, representing the first cause of death in CTD. The aim of this study is to highlight the role of Pulmonary Function Tests (PFTs) in the diagnosis and follow up of CTD patients. Main body: Rheumatoid Arthritis (RA) showed mainly an ILD with a Usual Interstitial Pneumonia (UIP) pattern in High-Resolution Chest Tomography (HRCT). PFTs are able to highlight a RA-ILD before its clinical onset and to drive follow up of patients with Forced Vital Capacity (FVC) and Carbon Monoxide Diffusing Capacity (DL CO ). In the course of Scleroderma Spectrum Disorders (SSDs) and Idiopathic Inflammatory Myopathies (IIMs), DL CO appears to be more sensitive than FVC in highlighting an ILD, but it can be compromised by the presence of PAH. A restrictive respiratory pattern can be present in IIMs and Systemic Lupus Erythematosus due to the inflammatory involvement of respiratory muscles, the presence of fatigue or diaphragm distress. Conclusions: The lung should be carefully studied during CTDs. PFTs can represent an important prognostic tool for diagnosis and follow up of RA-ILD, but, on their own, lack sufficient specificity or sensitivity to describe lung involvement in SSDs and IIMs. Several composite indexes potentially able to describe the evolution of lung damage and response to treatment in SSDs are under investigation. Considering the potential severity of these conditions, an HRCT jointly with PFTs should be performed in all new diagnoses of SSDs and IIMs. Moreover, follow up PFTs should be interpreted in the light of the risk factor for respiratory disease related to each disease

    An Evaluation of 10 Percent and 20 Percent Benzocaine Gels in Patients With Acute Toothaches: Efficacy, Tolerability and Compliance With Label Dose Administration Directions

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    Background The authors evaluated the efficacy and tolerability of 10 percent and 20 percent benzocaine gels compared with those of a vehicle (placebo) gel for the temporary relief of toothache pain. They also assessed the compliance with the label dose administration directions on the part of participants with toothache pain. Methods Under double-masked conditions, 576 participants self-applied study gel to an open tooth cavity and surrounding oral tissues. Participants evaluated their pain intensity and pain relief for 120 minutes. The authors determined the amount of gel the participants applied. Results The responders’ rates (the primary efficacy parameter), defined as the percentage of participants who had an improvement in pain intensity as exhibited by a pain score reduction of at least one unit on the dental pain scale from baseline for two consecutive assessments any time between the five- and 20-minute points, were 87.3 percent, 80.7 percent and 70.4 percent, respectively, for 20 percent benzocaine gel, 10 percent benzocaine gel and vehicle gel. Both benzocaine gels were significantly (P ≀ .05) better than vehicle gel; the 20 percent benzocaine gel also was significantly (P ≀ .05) better than the 10 percent benzocaine gel. The mean amount of gel applied was 235.6 milligrams, with 88.2 percent of participants applying 400 mg or less. Conclusions Both 10 percent and 20 percent benzocaine gels were more efficacious than the vehicle gel, and the 20 percent benzocaine gel was more efficacious than the 10 percent benzocaine gel. All treatments were well tolerated by participants. Practical Implications Patients can use 10 percent and 20 percent benzocaine gels to temporarily treat toothache pain safely

    Effects of Aging and Cyclosporin A on Collagen Turnover in Human Gingiva

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    BACKGROUND: WE AIMED AT CHARACTERIZING THE AGING GINGIVA ANALYZING: i) collagen content and turnover in human gingival tissues and fibroblasts obtained from healthy young and aging subjects. ii) the effect of cyclosporin A administration in human cultured gingival fibroblasts obtained from aging compared to young subjects. METHODS: Morphological analysis was performed on haematoxylin-eosin and Sirius red stained paraffin-embedded gingival biopsies from young and aging healthy subjects. The expression of the main genes and proteins involved in collagen turnover were determined by real time PCR, dot blot and SDS-zymography on cultured young and aging gingival fibroblasts, and after cyclosporin A administration. RESULTS: Our results suggest that in healthy aged people, gingival connective tissue is characterized by a similar collagen content and turnover. Collagen turnover pathways are similarly affected by cyclosporin A treatment in young and aging gingival fibroblasts. CONCLUSIONS: Cyclosporin A administration affects gingival collagen turnover pathways in young and aging fibroblasts at the same extent, suggesting that during aging cyclosporin A administration is not related to relevant collagen turnover modifications

    From current status to optimization of HCV treatment: Recommendations from an expert panel

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    Chronic hepatitis C virus (HCV) infection is a major public health problem at a global level, causing an enormous burden of hepatic and extra-hepatic morbidity and mortality. Treatment of chronic HCV (CHC) has been revolutionized in the last few years by the introduction of highly effective and well tolerated direct acting antiviral agents (DAAs) able to achieve >90% rates of sustained virological response (SVR) in many groups of patients, including those previously excluded from interferon-based regimens. For such reason interferon-free regimens are now the treatments of choice for all patients. Successful anti-HCV treatment can stop liver disease progression and can solve the HCV-related extra hepatic manifestations, eventually reducing both liver-related and overall mortality. Together with the rapidly accumulating data about the evolution of treatment landscape, different guidelines from national and international Liver Scientific Societies have been published until today. However, these recommendations may not be applied worldwide as, due to high treatment costs, most of them identify as priority groups only patients with advanced liver disease. Moreover some types of patients pose clinical management problems for which even the guidelines do not always provide useful answers. With the aim of treatment optimization by filling some of the gaps of the current guidelines and addressing the remaining unmet needs in practice, a group of Italian experts, experienced on treatment of HCV infection, met in Stresa in February 2016. The summary of all the considerations arising from this two-day meeting and the final statements are reported in this position paper

    Clinical-cytological-grading and phenotyping in patients with chronic rhinosinusitis with nasal polyps: The relevance in clinical practice

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    Chronic rhinosinusitis (CRS) includes two main phenotypes: without nasal polyps (CRSsNP) and with nasal polyps (CRSwNP). CRSwNP may be associated with comorbidity, mainly concerning asthma, aspirin intolerance, and allergy. CRSwNP patients may also be evaluated by clinical-cytological grading (CCG). The current study investigated the prevalence and characteristics of the different CCG and phenotypes in CRSwNP outpatients examined in clinical practice. This retrospective cross-sectional study enrolled 791 consecutive CRSwNP outpatients (424 males, mean age 48.8 years). In the total population, asthma was a common comorbidity (30.8%) as well as aspirin intolerance (24.8%), and allergy (50.8%). As concerns CCG-grading, 210 (26.5%) outpatients had low-grade, 366 (46.3%) medium, and 215 (27.2%) high. As regards cytological phenotypes, 87 (11%) had neutrophilic type, 371 (46.3%) eosinophilic, 112 (14.2%) mast cell, and 221 (27.9%) mixed. High-grade CCG was significantly associated with more frequent asthma, aspirin intolerance, allergy, recurrent surgery, and mixed cytological phenotype. Low-grade CCG was characterized by fewer comorbidities and operations, and neutrophilic phenotype. Therefore, the present study confirmed that CCG is a useful tool in the management of outpatients with CRSwNP. CRSwNP is frequently associated with asthma, aspirin intolerance, and allergy comorbidity. High-grade CCG is frequently characterized by a mixed cytological phenotype, thus, by more severe progress. These real-world outcomes underline that CRSwNP deserves adequate attention for careful management and optimal identification of the best-tailored therapy; CCG and cytological phenotyping could be fruitful tools in clinical practice. Asthma and aspirin intolerance should be adequately investigated in all CRS patients
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