13 research outputs found
Take a picture! The role of visual methods in understanding psychiatric patient's everyday life
Understanding the patient's experience of mental illness can foster better support for this population and greater partnership with healthcare professionals. This study aims to explore the application of visual methods in the psychiatric field and, in particular, the experience of people suffering from psychotic disorders because it is still an open question that has not been only partially empirically examined
Chromatic Pupillometry Findings in Alzheimer's Disease
Intrinsically photosensitive melanopsin retinal ganglion cells (mRGCs) are crucial for non-image forming functions of the eye, including the photoentrainment of circadian rhythms and the regulation of the pupillary light reflex (PLR). Chromatic pupillometry, using light stimuli at different wavelengths, makes possible the isolation of the contribution of rods, cones, and mRGCs to the PLR. In particular, post-illumination pupil response (PIPR) is the most reliable pupil metric of mRGC function. We have previously described, in post-mortem investigations of AD retinas, a loss of mRGCs, and in the remaining mRGCs, we demonstrated extensive morphological abnormalities. We noted dendrite varicosities, patchy distribution of melanopsin, and reduced dendrite arborization. In this study, we evaluated, with chromatic pupillometry, the PLR in a cohort of mild-moderate AD patients compared to controls. AD and controls also underwent an extensive ophthalmological evaluation. In our AD cohort, PIPR did not significantly differ from controls, even though we observed a higher variability in the AD group and 5/26 showed PIPR values outside the 2 SD from the control mean values. Moreover, we found a significant difference between AD and controls in terms of rod-mediated transient PLR amplitude. These results suggest that in the early stage of AD there are PLR abnormalities that may reflect a pathology affecting mRGC dendrites before involving the mRGC cell body. Further studies, including AD cases with more severe and longer disease duration, are needed to further explore this hypothesis
In Vivo Diagnosis of Synucleinopathies: A Comparative Study of Skin Biopsy and RT-QuIC
none13siTo determine whether: 1) the immunofluorescence (IF) is a reproducible technique in detecting misfolded α-synuclein (α-syn) in skin nerves; and subsequently 2) IF and RT-QuIC (both in skin and CSF) show a comparable in vivo diagnostic accuracy in distinguish synucleinopathies (SOPs) from non-synucleinopathies (non-SOPs) in a large cohort of patients.noneDonadio, Vincenzo; Wang, Zerui; Incensi, Alex; Rizzo, Giovanni; Fileccia, Enrico; Vacchiano, Veria; Capellari, Sabina; Magnani, Martina; Scaglione, Cesa; Stanzani Maserati, Michelangelo; Avoni, Patrizia; Liguori, Rocco; Zou, WenquanDonadio, Vincenzo; Wang, Zerui; Incensi, Alex; Rizzo, Giovanni; Fileccia, Enrico; Vacchiano, Veria; Capellari, Sabina; Magnani, Martina; Scaglione, Cesa; Stanzani Maserati, Michelangelo; Avoni, Patrizia; Liguori, Rocco; Zou, Wenqua
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Chromatic Pupillometry Findings in Alzheimers Disease.
Intrinsically photosensitive melanopsin retinal ganglion cells (mRGCs) are crucial for non-image forming functions of the eye, including the photoentrainment of circadian rhythms and the regulation of the pupillary light reflex (PLR). Chromatic pupillometry, using light stimuli at different wavelengths, makes possible the isolation of the contribution of rods, cones, and mRGCs to the PLR. In particular, post-illumination pupil response (PIPR) is the most reliable pupil metric of mRGC function. We have previously described, in post-mortem investigations of AD retinas, a loss of mRGCs, and in the remaining mRGCs, we demonstrated extensive morphological abnormalities. We noted dendrite varicosities, patchy distribution of melanopsin, and reduced dendrite arborization. In this study, we evaluated, with chromatic pupillometry, the PLR in a cohort of mild-moderate AD patients compared to controls. AD and controls also underwent an extensive ophthalmological evaluation. In our AD cohort, PIPR did not significantly differ from controls, even though we observed a higher variability in the AD group and 5/26 showed PIPR values outside the 2 SD from the control mean values. Moreover, we found a significant difference between AD and controls in terms of rod-mediated transient PLR amplitude. These results suggest that in the early stage of AD there are PLR abnormalities that may reflect a pathology affecting mRGC dendrites before involving the mRGC cell body. Further studies, including AD cases with more severe and longer disease duration, are needed to further explore this hypothesis
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Photoinduced Current Transient Spectroscopy on Metal Halide Perovskites: Electron Trapping and Ion Drift.
Metal halide perovskites (MHPs) are disruptive materials for a vast class of optoelectronic devices. The presence of electronic trap states has been a tough challenge in terms of characterization and thus mitigation. Many attempts based on electronic spectroscopies have been tested, but due to the mixed electronic-ionic nature of MHP conductivity, many experimental results retain a large ambiguity in resolving electronic and ionic charge contributions. Here we adapt a method, previously used in highly resistive inorganic semiconductors, called photoinduced current transient spectroscopy (PICTS) on lead bromide 2D-like ((PEA)2PbBr4) and standard 3D (MAPbBr3) MHP single crystals. We present two conceptually different outcomes of the PICTS measurements, distinguishing the different electronic and ionic contributions to the photocurrents based on the different ion drift of the two materials. Our experiments unveil deep level trap states on the 2D, ion-frozen (PEA)2PbBr4 and set new boundaries for the applicability of PICTS on 3D MHPs
Photoinduced Current Transient Spectroscopy on Metal Halide Perovskites: Electron Trapping and Ion Drift
International audienceMetal halide perovskites (MHPs) are disruptive materials for a vast class of optoelectronic devices. The presence of electronic trap states has been a tough challenge in terms of characterization and thus mitigation. Many attempts based on electronic spectroscopies have been tested, but due to the mixed electronic–ionic nature of MHP conductivity, many experimental results retain a large ambiguity in resolving electronic and ionic charge contributions. Here we adapt a method, previously used in highly resistive inorganic semiconductors, called photoinduced current transient spectroscopy (PICTS) on lead bromide 2D-like ((PEA)2PbBr4) and standard “3D” (MAPbBr3) MHP single crystals. We present two conceptually different outcomes of the PICTS measurements, distinguishing the different electronic and ionic contributions to the photocurrents based on the different ion drift of the two materials. Our experiments unveil deep level trap states on the 2D, “ion-frozen” (PEA)2PbBr4 and set new boundaries for the applicability of PICTS on 3D MHPs
Multimodal investigation of melanopsin retinal ganglion cells in Alzheimer's disease.
peer reviewed[en] OBJECTIVE: In Alzheimer's disease (AD), the presence of circadian dysfunction is well-known and may occur early in the disease course. The melanopsin retinal ganglion cell (mRGC) system may play a relevant role in contributing to circadian dysfunction. In this study, we aimed at evaluating, through a multimodal approach, the mRGC system in AD at an early stage of disease.
METHODS: We included 29 mild-moderate AD (70.9 ± 11 years) and 26 (70.5 ± 8 years) control subjects. We performed an extensive neurophtalmological evaluation including optical coherence tomography with ganglion cell layer segmentation, actigraphic evaluation of the rest-activity rhythm, chromatic pupillometry analyzed with a new data-fitting approach, and brain functional MRI combined with light stimuli assessing the mRGC system.
RESULTS: We demonstrated a significant thinning of the infero-temporal sector of the ganglion cell layer in AD compared to controls. Moreover, we documented by actigraphy the presence of a circadian-impaired AD subgroup. Overall, circadian measurements worsened by age. Chromatic pupillometry evaluation highlighted the presence of a pupil-light response reduction in the rod condition pointing to mRGC dendropathy. Finally, brain fMRI showed a reduced occipital cortex activation with blue light particularly for the sustained responses.
INTERPRETATION: Overall, the results of this multimodal innovative approach clearly document a dysfunctional mRGC system at early stages of disease as a relevant contributing factor for circadian impairment in AD providing also support to the use of light therapy in AD
Photoinduced Current Transient Spectroscopy on Metal Halide Perovskites: Electron Trapping and Ion Drift
Metal halide perovskites (MHPs) are disruptive materials
for a
vast class of optoelectronic devices. The presence of electronic trap
states has been a tough challenge in terms of characterization and
thus mitigation. Many attempts based on electronic spectroscopies
have been tested, but due to the mixed electronic–ionic nature
of MHP conductivity, many experimental results retain a large ambiguity
in resolving electronic and ionic charge contributions. Here we adapt
a method, previously used in highly resistive inorganic semiconductors,
called photoinduced current transient spectroscopy (PICTS) on lead
bromide 2D-like ((PEA)2PbBr4) and standard “3D”
(MAPbBr3) MHP single crystals. We present two conceptually
different outcomes of the PICTS measurements, distinguishing the different
electronic and ionic contributions to the photocurrents based on the
different ion drift of the two materials. Our experiments unveil deep
level trap states on the 2D, “ion-frozen” (PEA)2PbBr4 and set new boundaries for the applicability
of PICTS on 3D MHPs
Association of rs3027178 polymorphism in the circadian clock gene PER1 with susceptibility to Alzheimer's disease and longevity in an Italian population
: Many physiological processes in the human body follow a 24-h circadian rhythm controlled by the circadian clock system. Light, sensed by retina, is the predominant "zeitgeber" able to synchronize the circadian rhythms to the light-dark cycles. Circadian rhythm dysfunction and sleep disorders have been associated with aging and neurodegenerative diseases including mild cognitive impairment (MCI) and Alzheimer's disease (AD). In the present study, we aimed at investigating the genetic variability of clock genes in AD patients compared to healthy controls from Italy. We also included a group of Italian centenarians, considered as super-controls in association studies given their extreme phenotype of successful aging. We analyzed the exon sequences of eighty-four genes related to circadian rhythms, and the most significant variants identified in this first discovery phase were further assessed in a larger independent cohort of AD patients by matrix assisted laser desorption/ionization-time of flight mass spectrometry. The results identified a significant association between the rs3027178 polymorphism in the PER1 circadian gene with AD, the G allele being protective for AD. Interestingly, rs3027178 showed similar genotypic frequencies among AD patients and centenarians. These results collectively underline the relevance of circadian dysfunction in the predisposition to AD and contribute to the discussion on the role of the relationship between the genetics of age-related diseases and of longevity
THU-117-Evaluation of risk factors associated with failure to a first-line NS5A-containing regimen in HCV-infected patients naive to direct acting antivirals: Particular focus on natural resistance
Background and aims: This study aimed to evaluate the presence of natural resistance-associated- substitutions (RASs) and other pre-treatment risk-factors for failure in a large group of HCV-infected patients (pts) naive to direct-acting-antivirals (DAA) with an available outcome after their first-line NS5A inhibitor-containing regimen in Italy. Method: RASs in NS3/NS5A/NS5B (N = 1685/1497/1175) were analysed in 1947 DAA-naïve pts. Of them, 705 had an available outcome after a first-line NS5A-containing regimen recommended by the 2016/18 guidelines, with a baseline (BL) NS5A-test. HCV Sanger-sequencing was performed by home-made protocols. Potential differences between the sustained-virological-response (SVR) and virological-failure (VF) group were evaluated by Fisher’s exact test. A multivariable logistic-regression analysis was performed to define risk-factors associated to treatment-response. Results: Overall, 579/1947 (29.7%) pts showed at least one natural RASs, particularly NS5A-RAS was observed in 18.9% of pts. 705 pts (GT1a/b/g[200/214/1]-GT2a/c[84]-3a[141]-4a/d[65]) had an available outcome (656 with a SVR and 49 with a VF) after the following recommended NS5A- containing regimen: daclatasvir (DCV)/ledipasvir (LDV)/velpatasvir (VEL)+sofosbuvir (SOF)±ribavirin (RBV) (N = 125/130/161), 3D/2D (paritaprevir/ritonavir+ombitasvir ± dasabuvir)±RBV (N = 125/44), grazoprevir (GZR)+elbasvir (EBR)±RBV (N = 70), glecaprevir+pibrentasvir (G/P) (N = 50). By analysing retrospectively the BL samples, a higher prevalence of natural NS5A-RASs was observed before treatment in DAA-failures (18/49, 36.7%) vs SVR-pts (94/656, 14.3%; P < 0.001). Notably, ≥ 2 risk factors for failure were more frequently observed at BL among pts who experienced a VF to a DAA treatment (37/49, 75.5%) compared to those achieving SVR (295/656, 45.0%, P < 0.001). By multivariable logistic-regression high HCV-RNA, natural RAS, cirrhosis, previous IFN-failure were negatively associated with SVR (see figure). Interestingly, all 32 GT1-3 pts treated with G/P achieved SVR, with the exception of 1 GT3, who had a breakthrough and had at BL the NS5A RAS A30K and HCV-RNA > 800.000 IU/ml. All others were without (or only 1) risk-factor: notably none of them showed BL RASs regimen-related. Conclusion: The presence of specific pre-treatment risk-factor, such as RAS regimen-related, BL HCV-RNA > 800.000 IU/ml, cirrhosis and previous IFN-failure were associated with virological failure for some specific regimens and GTs