277 research outputs found

    Cerebral blood flow and cerebrovascular reactivity correlate with severity of motor symptoms in Parkinson’s disease

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    Background: Parkinson\u2019s disease (PD) is a progressive neurodegenerative disorder that is mainly characterized by movement dysfunction. Neurovascular unit (NVU) disruption has been proposed to be involved in the disease, but its role in PD neurodegenerative mechanisms is still unclear. The aim of this study was to investigate cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) within the regions belonging to the motor network, in patients with mild to moderate stages of PD. Methods: Twenty-eight PD patients (66.6 \ub1 8.6 years, 22 males, median [interquartile range, IQR] Hoehn & Yahr = 1.5 [1\u20131.9]) and 32 age- and sex-matched healthy controls (HCs) were scanned with arterial spin labeling (ASL) magnetic resonance imaging (MRI) for CBF assessment. ASL MRI was also acquired in hypercapnic conditions to induce vasodilation and subsequently allow for CVR measurement in a subgroup of 13 PD patients and 13 HCs. Median CBF and CVR were extracted from cortical and subcortical regions belonging to the motor network and compared between PD patients and HCs. In addition, the correlation between these parameters and the severity of PD motor symptoms [quantified with Unified Parkinson\u2019s Disease Rating Scale part III (UPDRS III)] was assessed. The false discovery rate (FDR) method was used to correct for multiple comparisons. Results: No significant differences in terms of CBF and CVR were found between PD patients and HCs. Positive significant correlations were observed between CBF and UPDRS III within the precentral gyrus, postcentral gyrus, supplementary motor area, striatum, pallidum, thalamus, red nucleus, and substantia nigra (pFDR < 0.05). Conversely, significant negative correlation between CVR and UPDRS III was found in the corpus striatum (pFDR < 0.05). Conclusion: CBF and CVR assessment provides information about NVU integrity in an indirect and noninvasive way. Our findings support the hypothesis of NVU involvement at the mild to moderate stages of PD, suggesting that CBF and CVR within the motor network might be used as either diagnostic or prognostic markers for PD

    Children with Cerebral Palsy can imagine actions like their normally developed peers

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    The present study aimed at assessing whether children with Cerebral Palsy (CP) can imagine object directed actions similarly to their normally developed peers. We asked children with CP (n = 12) and paired healthy controls (n = 12) to imagine in first person perspective eight daily actions, after observing them through videoclips presented on a computer screen. During motor imagery (MI) children were interrupted at a specific timepoint (e.g., at 2.5 s) from the start. Two frames extracted from the videoclips were then presented on the screen. One of the two depicted the correct timepoint at which the imagined action was interrupted, while the other represented an earlier or later timepoint. Children had to respond by pressing the key associated to the correct frame. Children also underwent VMIQ-2 questionnaire. Both groups performed similarly in the questionnaire and in the requested task, where they showed the same error rate. Errors mainly concerned the later frame, suggesting a similar strategy to solve the task in the two groups. The results support the view that children with CP can imagine actions similarly to their normally developed peers. This encourages the use of MI as a rehabilitative tool in children with motor impairment

    Modified percutaneous ethanol injection of parathyroid adenoma in primary hyperparathyroidism.

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    Surgery is the treatment of choice for symptomatic primary hyperparathyroidism; unlikely few patients do not meet established surgical criteria or have comorbid conditions that prohibit surgery. In these subjects, medical therapy alone offers little hope for a sustained long normocalcemic period. However percutaneous ethanol injection (PEI) may represent an alternative therapeutic procedure. It is currently in use for the treatment of secondary or tertiary hyperparathyroidism, however, few studies or case reports suggest it for the treatment of primary hyperparathyroidism. Moreover, little information is available about the long-term follow-up, where incomplete necrosis or the spreading of ethanol in the surrounding tissues is often reported. We believe that many of the side effects could be correlated to procedure itself. Taking these experiences into account, we have reasoned that in order to limit these side effects, we had to modify the standard PEI procedure. We reported this preliminary experience describing our modified PEI procedure

    A cryogenic liquid-mirror telescope on the moon to study the early universe

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    We have studied the feasibility and scientific potential of zenith observing liquid mirror telescopes having 20 to 100 m diameters located on the moon. They would carry out deep infrared surveys to study the distant universe and follow up discoveries made with the 6 m James Webb Space Telescope (JWST), with more detailed images and spectroscopic studies. They could detect objects 100 times fainter than JWST, observing the first, high-red shift stars in the early universe and their assembly into galaxies. We explored the scientific opportunities, key technologies and optimum location of such telescopes. We have demonstrated critical technologies. For example, the primary mirror would necessitate a high-reflectivity liquid that does not evaporate in the lunar vacuum and remains liquid at less than 100K: We have made a crucial demonstration by successfully coating an ionic liquid that has negligible vapor pressure. We also successfully experimented with a liquid mirror spinning on a superconducting bearing, as will be needed for the cryogenic, vacuum environment of the telescope. We have investigated issues related to lunar locations, concluding that locations within a few km of a pole are ideal for deep sky cover and long integration times. We have located ridges and crater rims within 0.5 degrees of the North Pole that are illuminated for at least some sun angles during lunar winter, providing power and temperature control. We also have identified potential problems, like lunar dust. Issues raised by our preliminary study demand additional in-depth analyses. These issues must be fully examined as part of a scientific debate we hope to start with the present article.Comment: 35 pages, 11 figures. To appear in Astrophysical Journal June 20 200

    Feasibility and Predictive Performance of a Triage System for Patients with Cancer During the COVID-19 Pandemic

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    Background: Triage procedures have been implemented to limit hospital access and minimize infection risk among patients with cancer during the coronavirus disease (COVID-19) outbreak. In the absence of prospective evidence, we aimed to evaluate the predictive performance of a triage system in the oncological setting. Materials and Methods: This retrospective cohort study analyzes hospital admissions to the oncology and hematology department of Udine, Italy, during the COVID-19 pandemic (March 30 to April 30, 2020). A total of 3,923 triage procedures were performed, and data of 1,363 individual patients were reviewed. Results: A self-report triage questionnaire identified 6% of triage-positive procedures, with a sensitivity of 66.7% (95% confidence interval [CI], 43.0%–85.4%), a specificity of 94.3% (95% CI, 93.5%–95.0%), and a positive predictive value of 5.9% (95% CI, 4.3%–8.0%) for the identification of patients who were not admitted to the hospital after medical review. Patients with thoracic cancer (odds ratio [OR], 1.69; 95% CI, 1.13–2.53, p =.01), younger age (OR, 1.52; 95% CI, 1.15–2.01, p <.01), and body temperature at admission ≥37°C (OR, 9.52; 95% CI, 5.44–16.6, p <.0001) had increased risk of positive triage. Direct hospital access was warranted to 93.5% of cases, a further 6% was accepted after medical evaluation, whereas 0.5% was refused at admission. Conclusion: A self-report questionnaire has a low positive predictive value to triage patients with cancer and suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) symptoms. Differential diagnosis with tumor- or treatment-related symptoms is always required to avoid unnecessary treatment delays. Body temperature measurement improves the triage process's overall sensitivity, and widespread SARS-CoV-2 testing should be implemented to identify asymptomatic carriers. Implications for Practice: This is the first study to provide data on the predictive performance of a triage system in the oncological setting during the coronavirus disease outbreak. A questionnaire-based triage has a low positive predictive value to triage patients with cancer and suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) symptoms, and a differential diagnosis with tumor- or treatment-related symptoms is mandatory to avoid unnecessary treatment delays. Consequently, adequate recourses should be reallocated for a triage implementation in the oncological setting. Of note, body temperature measurement improves the overall sensitivity of the triage process, and widespread testing for SARS-CoV-2 infection should be implemented to identify asymptomatic carriers

    First- and second-line treatment strategies for hormone-receptor (HR)-positive HER2-negative metastatic breast cancer: A real-world study

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    Background: Endocrine therapy (ET) plus cyclin-dependent-kinases 4/6 inhibitors (CDK4/6i) represents the standard treatment for luminal-metastatic breast cancer (MBC). However, prospective head-to-head comparisons are still lacking for 1st line (L) options, and it is still crucial to define the best strategy between 1st and 2nd L. Materials and methods: 717 consecutive luminal-MBC pts treated between 2008 and 2020 were analyzed at the Oncology Department of Aviano and Udine, Italy. Differences about survival outcomes (OS, PFS and PPS) were tested by log-rank test. The attrition rate (AR) between 1st and 2ndL was calculated. Results: At 1stL, pts were treated with ET (49%), chemotherapy (CT) (31%) and ET-CDKi (20%) while, at 2ndL, 33% received ET, 33% CT and 8% ET-CDKi. Overall AR was 10%, 7% for CT, 8% for ET and 17% for ET-CDKi. By multivariate analysis, 1stL ET-CDK4/6i showed a better mPFS1 and OS. Moreover, 2ndL ET-CDK4/6i demonstrated better mPFS2 compared to ET and CT. Notably, 1stL ET-CDKi resulted in higher mPFS than 2ndL ET-CDKi. Intriguingly, 1stL ET-CDK4/6i was associated with worse mPPS compared to CT and ET. Secondarily, 1stL ET-CDK4/6i followed by CT had worse OS compared to 1stL ET-CDK4/6i followed by ET. Notably, none of baseline characteristics at 2ndL influenced 2ndL treatment choice (ET vs. CT) after ET-CDKi. Conclusion: Our real-world data demonstrated that ET-CDKi represents the best option for 1stL luminal-MBC compared to ET and CT. Also, the present study pointed out that 2ndL ET, potentially combined with other molecules, could be a feasible option after CDK4/6i failure, postponing CT on later lines

    Quantum memory for photons: I. Dark state polaritons

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    An ideal and reversible transfer technique for the quantum state between light and metastable collective states of matter is presented and analyzed in detail. The method is based on the control of photon propagation in coherently driven 3-level atomic media, in which the group velocity is adiabatically reduced to zero. Form-stable coupled excitations of light and matter (``dark-state polaritons'') associated with the propagation of quantum fields in Electromagnetically Induced Transparency are identified, their basic properties discussed and their application for quantum memories for light analyzed.Comment: 13 pages, 6 figures, paragraph on photon echo adde
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