691 research outputs found

    Los peces (Chondrichthyes, Osteichthyes) del Plioceno inferior de Gran Canaria y Fuerteventura (Islas Canarias, España)

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    Fossil fish teeth are contained in marine deposits dated at ca 4.8 Ma found on the islands of Gran Canaria and Fuerteventura (Canary Islands, Spain). These islands, situated in the North Atlantic Subtropical Gyre, can be considered a mid-way stopover point between the Caribbean Sea, with the Central American Seaway about to close in this epoch, and the Mediterranean, in the first stage of its post-Messinian Gibraltar Seaway period. Accordingly, there existed extensive pantropical communication, particularly for nektonic animals capable of travelling large distances. In this paper, we present a number of fossil fishes, most of which are identified for the first time on the basis of their teeth: the Chondrichthyes species Carcharocles megalodon, Parotodus benedeni, Cosmopolitodus hastalis, Isurus oxyrinchus, Carcharias cf. acutissima, Carcharhinus cf. leucas, Carcharhinus cf. priscus, Galeocerdo cf. aduncus, and the Osteichthyes species Archosargus cinctus, Labrodon pavimentatum, and Diodon scillae. Coincidences are observed between these ichthyofauna and specimens found in the Azores Islands, the Pacific coast of America and the Mediterranean Sea.Los dientes fósiles de peces están contenidos en depósitos marinos datados en ca 4.8 Ma de las Islas de Gran Canaria y Fuerteventura (Islas Canarias, España). Estas islas, situadas en el Giro subtropical del Atlántico Norte, pueden considerarse una estación intermedia entre un Mar Caribe que estaba cercano al cierre del Paso de América Central, y el Mediterráneo en su primera etapa tras la apertura post-Mesiniense de Gibraltar. Ello permitía una comunicación pantropical para los animales del necton que eran capaces de desplazarse a grandes distancias. Se identifican por primera vez los peces Chondrichthyes Carcharocles megalodon, Parotodus benedeni, Cosmopolitodus hastalis, Isurus oxyrinchus, Carcharias cf. acutissima, Carcharhinus cf. leucas, Carcharhinus cf. priscus, Galeocerdo cf. aduncus y las species de Osteichthyes Archosargus cinctus, Labrodon pavimentatum y Diodon scillae. Se ha observado coincidencia entre los ejemplares canarios y los encontrados en las Islas Azores, las costas pacíficas de América y el mar Mediterráneo

    hTERT Transduction Extends the Lifespan of Primary Pediatric Low-Grade Glioma Cells While Preserving the Biological Response to NGF

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    The neurotrophin nerve growth factor (NGF) modulates the growth of human gliomas and is able to induce cell differentiation through the engagement of tropomyosin receptor kinase A (TrkA) receptor, although the role played in controlling glioma survival has proved controversial. Unfortunately, the slow growth rate of low-grade gliomas (LGG) has made it difficult to investigate NGF effects on these tumors in preclinical models. In fact, patient-derived low-grade human astrocytoma cells duplicate only a limited number of times in culture before undergoing senescence. Nevertheless, replicative senescence can be counteracted by overexpression of hTERT, the catalytic subunit of telomerase, which potentially increases the proliferative potential of human cells without inducing cancer-associated changes. We have extended, by hTERT transduction, the proliferative in vitro potential of a human LGG cell line derived from a pediatric pilocytic astrocytoma (PA) surgical sample. Remarkably, the hTERT-transduced LGG cells showed a behavior similar to that of the parental line in terms of biological responses to NGF treatment, including molecular events associated with induction of NGF-related differentiation. Therefore, transduction of LGG cells with hTERT can provide a valid approach to increase the in vitro life-span of patient-derived astrocytoma primary cultures, characterized by a finite proliferative potential

    Combining olfactory test and motion analysis sensors in Parkinson's disease preclinical diagnosis: A pilot study

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    Objectives: Preclinical diagnosis of Parkinson's disease (PD) is nowadays a topic of interest as the neuropathological process could begin years before the appearance of motor symptoms. Several symptoms, among them hyposmia, could precede motor features in PD. In the preclinical phase of PD, a subclinical reduction in motor skills is highly likely. In this pilot study, we investigate a step-by-step method to achieve preclinical PD diagnosis. Material and methods: We used the IOIT (Italian Olfactory Identification Test) to screen a population of healthy subjects. We identified 20 subjects with idiopathic hyposmia. Hyposmic subjects underwent an evaluation of motor skills, at baseline and after 1 year, using motion analysis sensors previously created by us. Results: One subject showed significant worsening in motor measurements. In this subject, we further conducted a dopaminergic challenge test monitored with the same sensors and, finally, he underwent [123I]-FP/CIT (DaTscan) SPECT brain imaging. The results show that he is probably affected by preclinical PD. Conclusions: Our pilot study suggests that the combined use of an olfactory test and motor sensors for motion analysis could be useful for a screening of healthy subjects to identify those at a high risk of developing PD

    Crilin: A CRystal calorImeter with Longitudinal InformatioN for a future Muon Collider

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    The measurement of physics processes at new energy frontier experiments requires excellent spatial, time, and energy resolutions to resolve the structure of collimated high-energy jets. In a future Muon Collider, the beam-induced backgrounds (BIB) represent the main challenge in the design of the detectors and of the event reconstruction algorithms. The technology and the design of the calorimeters should be chosen to reduce the effect of the BIB, while keeping good physics performance. Several requirements can be inferred: i) high granularity to reduce the overlap of BIB particles in the same calorimeter cell; ii) excellent timing (of the order of 100 ps) to reduce the out-of-time component of the BIB; iii) longitudinal segmentation to distinguish the signal showers from the fake showers produced by the BIB; iv) good energy resolution (less than 10%/sqrt(E)) to obtain good physics performance, as has been already demonstrated for conceptual particle flow calorimeters. Our proposal consists of a semi-homogeneous electromagnetic calorimeter based on Lead Fluoride Crystals (PbF2) readout by surface-mount UV-extended Silicon Photomultipliers (SiPMs): the Crilin calorimeter. In this paper, the performances of the Crilin calorimeter in the Muon Collider framework for hadron jets reconstruction have been analyzed. We report the single components characterizations together with the development of a small-scale prototype, consisting of 2 layers of 3x3 crystals each

    An integrated strategy for the prevention of SARS-CoV-2 infection in healthcare workers: a prospective observational study

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    BACKGROUND: Since the beginning of SARS-CoV-2 outbreak, a large number of infections have been reported among healthcare workers (HCWs). The aim of this study was to investigate the occurrence of SARS-CoV-2 infection among HCWs involved in the first management of infected patients and to describe the measures adopted to prevent the transmission in the hospital. METHODS: This prospective observational study was conducted between February 21 and April 16, 2020, in the Padua University Hospital (north-east Italy). The infection control policy adopted consisted of the following: the creation of the "Advanced Triage" area for the evaluation of SARS-CoV-2 cases, and the implementation of an integrated infection control surveillance system directed to all the healthcare personnel involved in the Advance Triage area. HCWs were regularly tested with nasopharyngeal swabs for SARS-CoV-2; body temperature and suggestive symptoms were evaluated at each duty. Demographic and clinical data of both patients and HCWs were collected and analyzed; HCWs' personal protective equipment (PPE) consumption was also recorded. The efficiency of the control strategy among HCWs was evaluated identifying symptomatic infection (primary endpoint) and asymptomatic infection (secondary endpoint) with confirmed detection of SARS-CoV-2. RESULTS: 7595 patients were evaluated in the Advanced Triage area: 5.2% resulted positive and 72.4% was symptomatic. The HCW team was composed of 60 members. A total of 361 nasopharyngeal swabs were performed on HCWs. All the swabs resulted negative and none of the HCWs reached the primary or the secondary endpoint. CONCLUSIONS: An integrated hospital infection control strategy, consisting of dedicated areas for infected patients, strict measures for PPE use and mass surveillance, is successful to prevent infection among HCWs

    A new ultrasound-guided percutaneous electrolysis and exercise treatment in patellar tendinopathy: three case reports.

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    Purpose: To present preliminary clinical results of the effects of a new treatment with percutaneous electrolysis directed to peripheral tendon and therapeutic resistance exercise, with or without the presence of degenerative zone. Methods: 3 patients with patellar tendinopathy aged 37-45 years with diagnostic of patellar tendinopathy with pain since 5-8 weeks were treated with a novel, less invasive electrolysis technique. Pain severity was measured by Numerical Pain Rating Scale (NPRS). Lower limb functionality was measured by a Victorian Institute of Sport Assessment questionnaire (VISA-P). A clinical interview and ultrasonography assesment were performed before study protocol were carried out. Each participants received 4 to 7 sessions of percutaneous electrolysis (350 μA, 80 s) leaving at least one week between sessions during a total of 8 weeks. During this time, subjects also were undergone a therapeutic exercise protocol of lower limbs resistance training. Results: Pain severity decreased after 3 weeks treatment (p = 0.01) and was practically abolished after 4-7 sessions at 8 weeks (p = 0.2). The lower limb functionality (VISA-P) increased after 3 weeks treatment and the major difference was found at 8 weeks post-intervention (p = 0.001). Thickness of the patellar tendon decreased after 8 weeks treatment (p = 0.01). Conclusions: The present work provides the first evidence that percutaneous electrolysis with a least invasive physiotherapy treatment targeted to peripheral tendon in combination with therapeutic resistance exercise diminished pain, improved funcitonality and showed a tendency to decreased thickness in subjects with patelallar tendinopathy

    Sutureless Perceval Aortic Valve Versus Conventional Stented Bioprostheses: Meta‐Analysis of Postoperative and Midterm Results in Isolated Aortic Valve Replacement

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    Background Aortic stenosis is the most common valvular disease and has a dismal prognosis without surgical treatment. The aim of this meta-analysis was to quantitatively assess the comparative effectiveness of the Perceval (LivaNova) valve versus conventional aortic bioprostheses. Methods and ResultsA total of 6 comparative studies were identified, including 639 and 760 patients who underwent, respectively, aortic valve replacement with the Perceval sutureless valve (P group) and with a conventional bioprosthesis (C group). Aortic cross-clamping and cardiopulmonary bypass duration were significantly lower in the P group. No difference in postoperative mortality was shown for the P and C groups (2.8% versus 2.7%, respectively; odds ratio [OR]: 0.99 [95% confidence interval (CI), 0.52-1.88]; P=0.98). Incidence of postoperative renal failure was lower in the P group compared with the C group (2.7% versus 5.5%; OR: 0.45 [95% CI, 0.25-0.80]; P=0.007). Incidence of stroke (2.3% versus 1.7%; OR: 1.34 [95% CI, 0.56-3.21]; P=0.51) and paravalvular leak (3.1% versus 1.6%; OR: 2.52 [95% CI, 0.60-1.06]; P=0.21) was similar, whereas P group patients received fewer blood transfusions than C group patients (1.161.2 versus 2.13 +/- 2.2; mean difference: 0.99 [95% CI, -1.22 to -0.75]; P=0.001). The incidence of pacemaker implantation was higher in the P than the C group (7.9% versus 3.1%; OR: 2.45 [95% CI, 1.44-4.17]; P=0.001), whereas hemodynamic Perceval performance was better (transvalvular gradient 23.42 +/- 1.73 versus 22.8 +/- 1.86; mean difference: 0.90 [95% CI, 0.62-1.18]; P=0.001), even during follow-up (10.98 +/- 5.7 versus 13.06 +/- 6.2; mean difference: -2.08 [95% CI, -3.96 to -0.21]; P=0.030). We found no difference in 1-year mortality
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