1,856 research outputs found

    Self-reported gait unsteadiness in mildly impaired neurological patients: an objective assessment through statistical gait analysis

    Get PDF
    Background Self-reported gait unsteadiness is often a problem in neurological patients without any clinical evidence of ataxia, because it leads to reduced activity and limitations in function. However, in the literature there are only a few papers that address this disorder. The aim of this study is to identify objectively subclinical abnormal gait strategies in these patients. Methods Eleven patients affected by self-reported unsteadiness during gait (4 TBI and 7 MS) and ten healthy subjects underwent gait analysis while walking back and forth on a 15-m long corridor. Time-distance parameters, ankle sagittal motion, and muscular activity during gait were acquired by a wearable gait analysis system (Step32, DemItalia, Italy) on a high number of successive strides in the same walk and statistically processed. Both self-selected gait speed and high speed were tested under relatively unconstrained conditions. Non-parametric statistical analysis (Mann-Whitney, Wilcoxon tests) was carried out on the means of the data of the two examined groups. Results The main findings, with data adjusted for velocity of progression, show that increased double support and reduced velocity of progression are the main parameters to discriminate patients with self-reported unsteadiness from healthy controls. Muscular intervals of activation showed a significant increase in the activity duration of the Rectus Femoris and Tibialis Anterior in patients with respect to the control group at high speed. Conclusions Patients with a subjective sensation of instability, not clinically documented, walk with altered strategies, especially at high gait speed. This is thought to depend on the mechanisms of postural control and coordination. The gait anomalies detected might explain the symptoms reported by the patients and allow for a more focused treatment design. The wearable gait analysis system used for long distance statistical walking assessment was able to detect subtle differences in functional performance monitoring, otherwise not detectable by common clinical examination

    Measurements and optimization of the light yield of a TeO2_2 crystal

    Full text link
    Bolometers have proven to be good instruments to search for rare processes because of their excellent energy resolution and their extremely low intrinsic background. In this kind of detectors, the capability of discriminating alpha particles from electrons represents an important aspect for the background reduction. One possibility for obtaining such a discrimination is provided by the detection of the Cherenkov light which, at the low energies of the natural radioactivity, is only emitted by electrons. This paper describes the method developed to evaluate the amount of light produced by a crystal of TeO2_2 when hit by a 511 keV photon. The experimental measurements and the results of a detailed simulation of the crystal and the readout system are shown and compared. A light yield of about 52 Cherenkov photons per deposited MeV was measured. The effect of wrapping the crystal with a PTFE layer, with the aim of maximizing the light collection, is also presented

    The Effect of Immunosuppressive Agents on the Induction of Nuclear Factors that Bind to Sites on the Interleukin 2 Promoter

    Get PDF
    Cyclosporin A (CSA), FK506, and glucocorticosteroids all inhibit the production of lymphokines by decreasing lymphokine gene expression. Previous experiments have defined six different sites that may contribute to the transcriptional control of the interleukin 2 (IL2) promoter, and for each, active nuclear binding factors are induced upon mitogenic stimulation. While dexamethasone markedly blocks the increase in IL2 mRNA in stimulated human blood T cells, we found that the drug does not block the appearance of factors that bind to the transcriptional control sites termed AP-1, AP-3, NF-kB, OCT1, B site, and NF-AT. In contrast, both CSA and FK506 have similar effects : the drugs cause modest decreases in AP-3 and NF-kB, and marked decreases in the activity of AP-1 and NF-AT Therefore, CSA and FK506, while chemically different, seem to act upon a similar pathway that leads to IL2 gene expression, whereas glucocorticoids do not affect this pathway

    Virus replication begins in dendritic cells during the transmission of HIV-1 from mature dendritic cells to T cells

    Get PDF
    Background: To initiate immunity, dendritic cells (DCs) capture antigens or viruses at body surfaces, undergo maturation to express T-cell costimulatory molecules, and then migrate to lymphoid organs. DCs at body surfaces can capture human immunodeficiency virus 1 (HIV-1), but mature DCs do not support replication of the virus unless T cells are added. The initial site for HIV-1 replication remains unknown and it is unclear whether replication can take place in DCs or whether the virus must first be transmitted from DCs to T cells. Results: We generated mature DCs from monocyte precursors. Upon infection with HIV-1, reverse transcription was completed only when T cells were added. When the reverse transcriptase inhibitor azidothymidine was added to the DCs during exposure to HIV-1, the DCs remained fully infectious, as long as the drug was removed just before culturing the DCs with T cells. HIV-1 variants that were engineered to undergo only one cycle of replication were able to infect DCs and replicate once in these cells. When T cells were added, newly produced HIV-1 Gag protein was exclusively localized to the DCs. With wild-type virus, subsequent rounds of replication took place in T cells. Soluble CD40 ligand (CD40L) and CD40L-transfected fibroblasts stimulated HIV-1 replication in purified mature DCs. Conclusions: Mature DCs provide a drug-resistant reservoir for HIV-1. This reservoir is activated within DCs by CD40L and upon interaction with T cells, and the virus then spreads rapidly to other T cells

    Screening of respiratory pathogens by Respiratory Multi Well System (MWS) r-gene™ assay in hospitalized patients

    Get PDF
    Novel respiratory viruses have been identified as possible agents of upper and lower respiratory tract infections. Multiplex real-time PCRs have been developed to identify clinically relevant respiratory pathogens. In this study, 178 respiratory samples already screened for influenza virus types A and B by Flu A/B ASR real-time PCR kit were retrospectively analyzed with the Respiratory Multi Well System (MWS) r-gene™ real-time PCR kit which detects a wide spectrum of respiratory pathogens. The goal was to demonstrate the importance of a wide spectrum screening compared to a single diagnostic request. The Flu A/B ASR kit detected influenza B virus in 1.7% of the samples (3/178) and no influenza A virus. The MWS r-gene™ kit detected influenza virus in 6.7% (12/178) of samples (0.6% influenza A, and 6.2% influenza B), while the overall detection rate for respiratory pathogens was 54% (96/178). Co-infections were detected in 8/178 (4.5%) samples. Adenovirus was the infectious agent detected most frequently, followed by respiratory syncytial virus. The risk of being infected by respiratory syncytial virus is almost threefold higher in patients older than 65 years compared to the younger age group (OR:2.7, 95% CI: 1.2-6.2). Wide spectrum screening of respiratory pathogens by real-time PCR is an effective means of detecting clinically relevant viral pathogens

    Performance of the PADME calorimeter prototype at the DAΦ\PhiNE BTF

    Full text link
    The PADME experiment at the DAΦ\PhiNE Beam-Test Facility (BTF) aims at searching for invisible decays of the dark photon by measuring the final state missing mass in the process e+eγ+Ae^+e^- \to \gamma+ A', with AA' undetected. The measurement requires the determination of the 4-momentum of the recoil photon, performed using a homogeneous, highly segmented BGO crystals calorimeter. We report the results of the test of a 5×\times5 crystals prototype performed with an electron beam at the BTF in July 2016

    Cancer treatment-induced oral mucositis

    Get PDF
    Oral mucositis is one of the main complications in non-surgical cancer treatments. It represents the major dose-limiting toxicity for some chemotherapeutic agents, for radiotherapy of the head and neck region and for some radiochemotherapy combined treatments. Many reviews and clinical studies have been published in order to define the best clinical protocol for prophylaxis or treatment of mucositis, but a consensus has not yet been obtained. This paper represents an updated review of prophylaxis and treatment of antineoplastic-therapy-related mucositis using a MEDLINE search up to May 2006, in which more than 260 clinical studies have been found. They have been divided according to antineoplastic therapy (chemotherapy, radiotherapy, chemo-radiotherapy, high-dose chemotherapy). The prophylactic or therapeutic use of the analysed agents, the number of enrolled patients and the study design (randomized or not) were also specified for most studies. Accurate pre-treatment assessment of oral cavity hygiene, frequent review of symptoms during treatment, use of traditional mouthwashes to obtain mechanical cleaning of the oral cavity and administration of some agents like benzydamine, imidazole antibiotics, tryazolic antimycotics, povidone iodine, keratinocyte growth factor and vitamin E seem to reduce the intensity of mucositis. Physical approaches like cryotherapy, low energy Helium-Neon laser or the use of modern radiotherapy techniques with the exclusion of the oral cavity from radiation fields have been shown to be efficacious in preventing mucositis onset. Nevertheless a consensus protocol of prophylaxis and treatment of oral mucositis has not yet been obtained

    Synthesis and biological evaluation of phosphonated dihydroisoxazole nucleosides

    Get PDF
    Phosphonated isoxazolinyl nucleosides have been prepared via 1,3-dipolar cycloaddition reaction of nitrile oxides with corresponding vinyl or allyl nucleobases for antiviral studies. The cytotoxicity, the anti-HSV activity and the RT-inhibitory activity of the obtained compounds were evaluated and compared with those of AZT and diethyl{(10SR,40RS)-10-[[(5-methyl-2,4-dioxo-3,4- dihydropyrimidin-1(2H)-yl)]-30-methyl-20-oxa-30-azacyclopent-40-yl]}methylphosphonate, a saturated phosphonated dihydroisoxazole nucleoside analogue
    corecore