107 research outputs found

    Functional MR Imaging Correlates of Neuropsychological Impairment in Primary-Progressive Multiple Sclerosis

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    BACKGROUND AND PURPOSE: Cognitive deficits affect ≤30% of patients with PPMS. We investigated the functional correlates of cognitive network dysfunction in patients with PPMS and their correlation with the extent of structural MR imaging damage. MATERIALS AND METHODS: From 16 right-handed patients with PPMS and 17 matched controls, structural and fMRIs (during the performance of the 2-back task) were acquired. Neuropsychological tests exploring memory, attention, and frontal lobe cognitive domains were administered. T2 LL, NBV, and CC areas were measured. RESULTS: Six patients with PPMS were CI. Structural MR imaging measures did not differ between patients who were CI and those who were CP. Compared with patients who were CI, patients who were CP had increased activations of the left caudate nucleus, PFC, and inferior parietal lobule. Compared with controls and patients who were CP, patients who were CI had increased activations of the SII, cerebellum, and insula. Compared with controls, they also had increased activations of the right precentral gyrus and a reduced recruitment of the left PFC. In patients with PPMS, a decreased composite cognitive score correlated with increased activity of the cerebellum, insula, and SII, as well as decreased PFC activity. T2 LL correlated with decreased PFC recruitment and increased SII recruitment. CONCLUSIONS: In PPMS, an increased recruitment of cognitive-related networks might represent a functional reserve with the potential to limit the severity of cognitive impairment. The accumulation of T2 lesions and the consequent exhaustion of frontal lobe plasticity might contribute to cognitive impairment in PPMS

    Sneaking into a Hotspot of Biodiversity: Coverage and Integrity of a Rhodolith Bed in the Strait of Sicily (Central Mediterranean Sea)

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    Habitat mapping, physical characteristics and benthic community of a rhodolith bed in the Pelagie Islands (Strait of Sicily, Mediterranean Sea) were studied through Multi–Beam Echo–Sounder (MBES), Remotely Operated Vehicle (ROV) and grab samples. The geomorphological analysis revealed an articulated and wide rhodolith bed; video inspections highlighted a bed with high coverage, few sandy patches and with a prevalence of the boxwork morphotype. A total of 207 taxa with 876 specimens were identified, and Polychaeta was the dominant taxon. Linguimaera caesaris, a Lessepsian benthic amphipod, was recorded in all sampling sites, and its presence represents an input to deepen the benthic assemblage research on the rhodolith bed. In terms of morphotype composition, dead/live ratio and species variability, the bed variability indicated a good status of health, although trawling signs were detected through ROV videos. The present study broadens the knowledge on Mediterranean rhodolith beds and supports the importance of survey and monitoring activities for the conservation and management of this important habitat

    Preliminary observations of caulerpin accumulation from the invasive Caulerpa cylindracea in native Mediterranean fish species

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    Recent studies have shown that the Mediterranean white sea bream Diplodus sargus includes the invasive green alga Caulerpa cylindracea in its diet, with consequent metabolic and enzymatic alterations. As a result of this novel alimentary habit, the bioactive algal red pigment caulerpin has been detected in its tissues. However, this may not be an isolated case: other fish species have also been reported to feed on C. cylindracea, although the possible accumulation of caulerpin in their tissues has not yet been investigated. In this report, we analysed stomach contents and caulerpin levels in the native sparid species Spondyliosoma cantharus, Sarpa salpa, and Diplodus vulgaris, and in the scarid Sparisoma cretense, along with the Lessepsian siganid Siganus luridus. C. cylindracea was found in the stomachs of all but one fish species, the exception being S. cretense, in which prey items could not be determined due to the high degree of digestion. Chemical analysis of fish tissues revealed that only S. cantharus and S. salpa accumulated caulerpin, while no traces of the compound were detected in the other species. Despite intense research efforts on natural products obtained from C. cylindracea, a complete picture of the impacts caused by fish including this alga in their diet has not been elucidated. The identification of caulerpin in other Mediterranean native fish suggests a need for further research in order to assess the possible transfer of such molecules to humans through seafood consumption

    Bathymetric and longitudinal distribution analyysis of the rockfish Helicolenus Dactylopterus (Delaroche, 1809) in the southern Tyrrhenian Sea (central Mediterranean)

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    This study provides information on bathymetric and longitudinal distribution heterogeneity of the rockfish Helicolenus dactylopterus in the southern Tyrrhenian Sea. Data were drawn from experimental bottom trawl (1996-2002) plus bottom trap (2001-02) surveys. The frequency of occurrence and mean relative density (N/km2) and biomass (kg/km2) indexes were calculated for two survey seasons (spring and autumn), four geographic sectors and three depth strata. MANOVA was used to test fish abundance among years, sectors and strata. Analysis of the length-frequency distributions was carried out by two-way (gears and depths) ANOVA, post hoc multiple comparisons for testing differences among depths and Student’s t test for testing differences between gears. Length-weight relationship was also estimated and the allometric coefficient was tested with the Student’s t test. The results showed a significant positive bathymetric gradient of sizes both for trawl and trap surveys; at same depths, fish caught by traps were significantly longer than those caught by trawl. In spring surveys, significant differences were found among strata for both abundance indexes; in autumn surveys, significant differences between depth strata were found only for density indices. The distribution and abundance patterns of H. dactylopterus along the southern Tyrrhenian Sea was homogeneous among sectors. Length-weight relationship showed a significant positive allometric growth

    Elucidating food webs in infralitoral rocky coastal habitats invaded by Caulerpa cylindracea (Sonder 1845)

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    Invasive species including Caulerpa cylindracea affect coastal benthic communities inducing structural changes. To assess effects in rocky ecosystems, food webs have been depicted based on stable isotopic data collected from invertebrates and fishes at invaded and non-invaded coastal areas. Isotopic values of invertebrates were slightly higher in invaded than non-invaded habitats of Lampedusa Island, however no significant differences were found. Invasive fish Siganus luridus and native Sparisoma cretense had similar isotopic signatures indicating similar food sources

    Crustacean fishery with bottom traps in an area of the southern Tyrrhenian Sea: species composition, abundance and biomass

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    The north-eastern coast of Sicily is characterized by deep, steep bottoms, not easily exploitable by trawl fishery. In this area few fishermen use bottom traps to catch shrimps and Norway lobsters. Our studies were aimed at identifying the species' composition, abundance and biomass of crustaceans exploitable by bottom traps in this area. Monthly samples over one year were obtained from two lines of 30 baited traps each, at depths between 100 and 500 m. One line was placed in an area usually exploited by this fishery; the other line was used in the unexploited deepest bottoms. Trapped specimens were counted and weighed. ANOVA test, post hoc multiple comparisons and Student's t test were applied on abundance and biomass data, for testing differences between areas, among seasons and species. During 22 fishing days, 23 species characteristic of the bathyal mud assemblage were caught, 8 of which were not considered commercial. Plesionika edwardsii was the most important species, recorded in the whole bathymetric range investigated; Nephrops norvegicus was significantly higher in terms of biomass in the unexploited area. The discard, of slight importance, was mostly represented by the crab Liocarcinus depurator. Spring season yielded the best catches in both areas, showing the highest values for both abundance and biomas

    Morphometric aspects of Scyllarides latus

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    The slipper lobster, Scyllarides latus (Latreille, 1803), is the only representative species of the genusScyllarides in the Mediterranean Sea. In this study, we examined some biological aspects of this species sampled in the Straits of Messina. The specimens were sexed, measured and weighed. The relationships between body measurements (length and width of the carapace, antennal length) and length-weight relationship were calculated. Furthermore, the correlation matrix (Pearson’s coefficient) was calculated. Two hundred specimens were collected, ranging in size from 81 to 305 mm in total length, and between 21 and 1490 g in weight. A rare juvenile of 39 mm CL was recorded. A sex ratio of 1:1 was found. The carapace length – weight relationship was almost isometric. The wide size range sampled and the presence of a juvenile, indicate an interesting habitat for studying the presence and growth of Scyllarides latus in the Straits of Messina

    Fenomeno Caulerpa 2010-2013. Rapporto sull'evoluzione delle specie aliene nel Canale di Sicilia

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    Gli studi effettuati da ARPA-Sicilia, ISPRA e CNR-IAMC hanno perseguito l’obiettivo principale di monitorare e valutare l’impatto della diffusione delle alghe indagate, attraverso l’analisi dell’evoluzione spazio-temporale del fenomeno e la caratterizzazione eco-tossicologica delle aree di pesca maggiormente interessate dalla presenza delle caulerpe. In particolare Le ricerche di ARPA-Sicilia sono state mirate a: - Definire le aree di studio principalmente interessate dal fenomeno di diffusione delle due alghe aliene; - Caratterizzare da un punto di vista ambientale le aree oggetto d’indagine; - Valutare le pressioni antropiche che insistono lungo le coste delle aree indagate; - Stimare l’influenza che le pressioni antropiche possono esercitare sulla diffusione della Caulerpa; - Indagare l’andamento spazio-temporale della distribuzione di Caulerpa in specifiche aree di indagine. Gli studi condotti da ISPRA hanno puntato a: - Valutare possibili interferenze dell’alga con le attività di pesca, l’intasamento delle reti e la riduzione della pescabilità dell’attrezzo; - Rilevare l’eventuale diversità tra aree con insediamento e prive di insediamento; - Avviare l’introduzione di buone pratiche per evitare che la pesca possa rappresentare un ulteriore vettore di invasioni secondarie attraverso disseminazione dei frammenti e propaguli dell’alga; - Definire comportamenti alieutici nel tempo utili alla mitigazione del potenziale impatto della pesca sulle risorse nelle aree colpite; - Istituire in tutta l’area di studio e, in particolare, nell’arcipelago delle Pelagie, un “Osservatorio delle Specie Aliene” per svolgere attività di monitoraggio sulla diffusione delle specie aliene, al fine di formulare proposte gestionali mirate alla salvaguardia degli ecosistemi e delle attività economiche di pesca. Le indagini realizzate dal CNR-IAMC hanno avuto come obiettivi principali: - Confrontare le caratteristiche dei popolamenti bentonici associati a praterie di Posidonia oceanica della Sicilia meridionale interessate dall’invasione di Caulerpa taxifolia var. distichophylla con quelle di popolamenti associati a posidonieti di località limitrofe non colpite dal fenomeno; - Confrontare la struttura trofica della comunità bentonica associata a matte di Posidonia oceanica in località invase e non invase da alghe aliene del genere Caulerpa della Sicilia meridionale; - Valutare gli effetti dell’invasione di Caulerpa racemosa var. cylindracea sulla struttura e sulla funzione di popolamenti macrobentonici sessili di fondo duro dell’infralitorale

    Applying multidimensional computerized adaptive testing to the MSQOL-54: a simulation study

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    Background: The Multiple Sclerosis Quality of Life-54 (MSQOL-54) is one of the most commonly-used MS-specific health-related quality of life (HRQOL) measures. It is a multidimensional, MS-specific HRQOL inventory, which includes the generic SF-36 core items, supplemented with 18 MS-targeted items. Availability of an adaptive short version providing immediate item scoring may improve instrument usability and validity. However, multidimensional computerized adaptive testing (MCAT) has not been previously applied to MSQOL-54 items. We thus aimed to apply MCAT to the MSQOL-54 and assess its performance. Methods: Responses from a large international sample of 3669 MS patients were assessed. We calibrated 52 (of the 54) items using bifactor graded response model (10 group factors and one general HRQOL factor). Then, eight simulations were run with different termination criteria: standard errors (SE) for the general factor and group factors set to different values, and change in factor estimates from one item to the next set at < 0.01 for both the general and the group factors. Performance of the MCAT was assessed by the number of administered items, root mean square difference (RMSD), and correlation. Results: Eight items were removed due to local dependency. The simulation with SE set to 0.32 (general factor), and no SE thresholds (group factors) provided satisfactory performance: the median number of administered items was 24, RMSD was 0.32, and correlation was 0.94. Conclusions: Compared to the full-length MSQOL-54, the simulated MCAT required fewer items without losing precision for the general HRQOL factor. Further work is needed to add/integrate/revise MSQOL-54 items in order to make the calibration and MCAT performance efficient also on group factors, so that the MCAT version may be used in clinical practice and research

    The brief international cognitive assessment for multiple sclerosis (BICAMS): Normative values with gender, age and education corrections in the Italian population

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    Background: BICAMS (Brief International Cognitive Assessment for Multiple Sclerosis) has been recently developed as brief, practical and universal assessment tool for cognitive impairment in MS subjects. It includes the Symbol Digit Modalities Test (SDMT), the California Verbal Learning Test-2 (CVLT2) and the Brief Visuospatial Memory Test-Revised (BVMT-R) . In this study we aimed at gathering regression based normative data for the BICAMS battery in the Italian population.Methods: Healthy subjects were consecutively recruited among patient friends and relatives. Corrections for demographics were calculated using multivariable linear regression models. Test-retest reliability was assessed using the Pearson correlation coefficient.Results: The BICAMS battery was administered to 273 healthy subjects (180 women, mean age 38.9 ± 13.0 years, mean education 14.9 ± 3.0 years). Test-retest reliability was good for all the tests.Conclusions: The study provided normative data of the BICAMS for the Italian population confirming good test-retest reliability which can facilitate the use of the battery in clinical practice, also for longitudinal patient assessments
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