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PURPOSE: To assess current clinical practices throughout Europe with respect to acquisition, implementation, evaluation, and interpretation of language functional MRI (fMRI) in epilepsy patients. METHODS: An online survey was emailed to all European Society of Neuroradiology members (n = 1662), known associates (n = 6400), and 64 members of European Epilepsy network. The questionnaire featured 40 individual items on demographic data, clinical practice and indications, fMRI paradigms, radiological workflow, data post-processing protocol, and reporting. RESULTS: A total of 49 non-duplicate entries from European centers were received from 20 countries. Of these, 73.5% were board-certified neuroradiologists and 69.4% had an in-house epilepsy surgery program. Seventy-one percent of centers performed fewer than five scans per month for epilepsy. The most frequently used paradigms were phonemic verbal fluency (47.7%) and auditory comprehension (55.6%), but variants of 13 paradigms were described. Most centers assessed the fMRI task performance (75.5%), ensured cognitive-task adjustment (77.6%), trained the patient before scanning (85.7%), and assessed handedness (77.6%), but only 28.6% had special paradigms for patients with cognitive impairments. fMRI was post-processed mainly by neuroradiologists (42.1%), using open-source software (55.0%). Reporting was done primarily by neuroradiologists (74.2%). Interpretation was done mainly by visual inspection (65.3%). Most specialists (81.6%) were able to determine the hemisphere dominance for language in more than 75% of exams, attributing failure to the patient not performing the task correctly. CONCLUSION: This survey shows that language fMRI is firmly embedded in the preoperative management of epilepsy patients. The wide variety of paradigms and the use of non-CE-marked software underline the need for establishing reference standards.
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Epilepsia/diagnóstico por imagen , Pruebas del Lenguaje , Imagen por Resonancia Magnética , Pautas de la Práctica en Medicina/estadística & datos numéricos , Mapeo Encefálico/métodos , Europa (Continente) , Humanos , Interpretación de Imagen Asistida por Computador , Encuestas y CuestionariosRESUMEN
BACKGROUND: In 2014, the Italian Study Group of Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health (GISIO-SItI), in collaboration with the National Association of Medical Hospital Managers (ANMDO), conducted a survey on the availability of procedures for cleaning and disinfecting ambulances in order to assess the practices in use. METHODS: An online questionnaire was prepared through the Survey Monkey® platform and a web link access was sent to a convenience sample of ANMDO doctors working in healthcare management in public and private healthcare facilities. RESULTS: Ninety-six questionnaires were collected (26% response rate). In 73% of cases there was a procedure for cleaning and disinfecting ambulances, which had been produced at a company level (67%) and involved various professionals. In 21% of cases the procedure had been prepared in expectation of an epidemic or following an epidemic (5%). The recommendations had been presented to the staff (90%), in 28% of cases through training events with verification of the knowledge acquired. Monitoring of the implementation of the procedure is planned in the majority of cases (88%), mainly through direct observation (92%). In 67% of cases the tender specifications for ambulance services did not include a section dedicated to cleaning and disinfection and, in the absence of a procedure, this was provided by the hospital in only 51% of case. CONCLUSION: This survey represented a first step towards the development of guidelines for standardising procedures and providing indications useful for their evaluation and monitoring their implementation.
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Ambulancias/normas , Desinfección/normas , Guías como Asunto/normas , Tareas del Hogar/normas , Desinfección/métodos , Contaminación de Equipos/prevención & control , Humanos , Higiene , Italia , Sociedades Médicas , Encuestas y Cuestionarios/estadística & datos numéricosRESUMEN
BACKGROUND/AIM: Low dose rate brachytherapy has been used as salvage therapy for locally recurrent prostate cancer (PC) after primary external beam radiation therapy (EBRT), along with surgery and cryotherapy. All these techniques, in particular, when applied to the whole gland, involve a relatively high risk of toxicity and may worsen the patient's quality of life. Our aim is to evaluate the results of whole-gland salvage brachytherapy (SBT) after primary EBRT in terms of toxicity, functional outcomes, and efficacy. MATERIALS AND METHODS: We retrospectively reviewed clinical data on 19 patients consecutively treated with SBT at our institution between June 2012 and November 2015. Local recurrences were identified with 11C-choline positron emission tomography/computed tomography and pelvic magnetic resonance imaging after biochemical recurrence according to Phoenix criteria (prostate-specific antigen nadir + 2). Low dose rate brachytherapy was performed by 125I permanent seeds implantation to the whole prostate gland, with a prescription dose of 130 Gy. At the time of SBT, only 2 patients were receiving androgen deprivation therapy. Acute and late toxicities were recorded using the CTCAE 4.0 scoring system. Quality of life was assessed using IPSS (International Prostate Symptoms Score) and IIEF (International Index of Erectile Function) questionnaires at baseline and 6, 12, and 24 months after SBT, and the respective mean values were compared using Student t test. Biochemical relapse-free survival (BRFS) was also calculated. RESULTS: Median follow-up after SBT was 24 months. Of 19 patients, 2 patients experienced a G3 cystitis (10.2%) and 1 patient experienced a G4 proctitis (5.3%), respectively. Mean pre-SBT IPSS scores and 6, 12, and 24 months after SBT were 5.84, 10.22, 15.72, and 8.10, respectively. Mean pre-SBT IIEF scores and 6, 12, and 24 months after SBT were 8.42, 3.55, 7.89, and 6.40, respectively. At the time of analysis, only 2 patients showed a biochemical relapse (3-year BRFS 85.2%). The Student t test demonstrated a worsening of functional outcome 6 months and 1 year after treatment but a subsequent improvement 2 years after SBT. CONCLUSIONS: Salvage brachytherapy for recurrent PC after primary EBRT seems to be a feasible treatment for selected patients. Our series revealed a severe toxicity peak 6 months and 1 year after local re-treatment and then they decrease. Early BRFS rates are good. However, these are very preliminary results so further patient accrual, long-term follow-up, and prospective trials are needed in the future.
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BACKGROUND: Ambrosia is an annual anemophilous weed producing allergenic pollen affecting public health in European countries. In Italy, the most infested region is Lombardy where, in some areas, it is the major cause of hay fever. In the Parma district, until 2007, Ambrosia seemed to be very rare, despite an observed increase of Seasonal Pollen Index (SPI), of pollen peak value and of asthma among ragweed sensitized patients. The aims of this study were to calculate ragweed pollen season and trends from 1996 to 2015, to assess the relationships between pollen season characteristics and selected meteorological data, to map plants in the territory and to evaluate the presence of beetle Ophraella communa (Ophraella), known as an eater of Ambrosia leaves. METHODS: The following pollination parameters: start, end, duration, peak concentration date, peak values, SPI and the following climatic parameters: temperature, relative humidity, rainfall, were analyzed. The ragweed plants sites were mapped and the presence of Ophraella was assessed during naturalistic activities. RESULTS: Significant SPI and pollen peak value increase until 2011 were observed, but recently, 2012-2015 vs 2009-2011, a strong reduction (about 50%) of these parameters was observed. The spring average air temperature increased significantly. The results of the correlation analysis showed Ambrosia season characteristics significantly related. We identified the sites source of Ambrosia, even downtown at the confluence between Parma and Baganza rivers. Ophraella was observed for the first time in 2014. CONCLUSIONS: The results showed the spread of ragweed plants over the territory and the risk of allergy increase that ragweed could cause. It remains to evaluate the role of the Ophraella in the reduction of Ambrosia pollen concentration. It is important to consider the potential risk Ophraella may represent for sunflower and other taxonomically related crop plants and other native and exotic species. The lack of initiatives by the Health Authorities to prevent and to contrast the spread of Ambrosia in the Parma area could cause public health consequences and an increase in health expenditures.
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Contaminantes Atmosféricos , Ambrosia , Monitoreo del Ambiente , Polen , Rinitis Alérgica Estacional/prevención & control , Italia , Estaciones del Año , Factores de TiempoRESUMEN
OBJECTIVE: Promoting four healthy behaviours among preschool children:⩾4 servings of fruit and vegetables/day, ⩾2 h/day of active play, ⩽1 h per day of TV-watching and 0 sugar sweetened beverages/day. METHODS: We conducted a c-RCT on 425 3-year-old children at 16 childcare centres based in Cesena, Italy. We randomly allocated eight childcare centres (199 children) to the intervention group and eight childcare centres (226 children) to the control group. All the randomized childcare centres completed our study protocol. Parents recorded their children's target behaviours at home over 3 Saturdays, at baseline and at follow-up. Then trained nurses measured children's weight and height. We conducted a 6-month-long intervention trial in local health care centres where nurses and primary care pediatricians, respectively, conducted two subsequent motivational interviews with parents to encourage children's healthy behaviours at home. At the same time, teachers involved children in learning experiences about healthy behaviours. Our primary outcome is a children's combined health behaviour score (CHBS) at home. Our secondary outcomes measure the BMI z-score and the percentage of children that show a BMI trajectory crossing upward. After collecting the CHBS and BMI data at baseline as well as at 1- and 2-year follow-ups, we performed an Intent-to-Treat (ITT) analysis. RESULTS: After 2 years from baseline, 48.4% of intervention group children showed a low-risk CHBS in comparison with 28.0% of control group children. A multilevel analysis showed that they were by far more likely to achieve low-risk scores (adjusted OR: 3.41; 95% CI: 1.48-7.88; P=0.004). Our BMI outcomes showed no significant difference between groups. CONCLUSIONS: A multidimensional educational intervention, which consists of motivational interviews with parents and teacher-led learning experiences for children, improved preschool children's CHBS in the long term without influencing the outcomes of BMI z-score and BMI increase.
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Conducta Infantil , Conductas Relacionadas con la Salud , Educación en Salud , Estilo de Vida Saludable , Padres/educación , Bebidas , Índice de Masa Corporal , Guarderías Infantiles , Preescolar , Análisis por Conglomerados , Ejercicio Físico , Femenino , Frutas , Humanos , Italia , Masculino , Padres/psicología , Obesidad Infantil/prevención & control , VerdurasRESUMEN
Diffusion Weighted Imaging is extremely important for the diagnosis of probable sporadic Jakob-Creutzfeldt disease, the most common human prion disease. Although visual assessment of DWI MRI is critical diagnostically, a more objective, quantifiable approach might more precisely identify the precise pattern of brain involvement. Furthermore, a quantitative, systematic tracking of MRI changes occurring over time might provide insights regarding the underlying histopathological mechanisms of human prion disease and provide information useful for clinical trials. The purposes of this study were: 1) to describe quantitatively the average cross-sectional pattern of reduced mean diffusivity, fractional anisotropy, atrophy and T1 relaxation in the gray matter (GM) in sporadic Jakob-Creutzfeldt disease, 2) to study changes in mean diffusivity and atrophy over time and 3) to explore their relationship with clinical scales. Twenty-six sporadic Jakob-Creutzfeldt disease and nine control subjects had MRIs on the same scanner; seven sCJD subjects had a second scan after approximately two months. Cortical and subcortical gray matter regions were parcellated with Freesurfer. Average cortical thickness (or subcortical volume), T1-relaxiation and mean diffusivity from co-registered diffusion maps were calculated in each region for each subject. Quantitatively on cross-sectional analysis, certain brain regions were preferentially affected by reduced mean diffusivity (parietal, temporal lobes, posterior cingulate, thalamus and deep nuclei), but with relative sparing of the frontal and occipital lobes. Serial imaging, surprisingly showed that mean diffusivity did not have a linear or unidirectional reduction over time, but tended to decrease initially and then reverse and increase towards normalization. Furthermore, there was a strong correlation between worsening of patient clinical function (based on modified Barthel score) and increasing mean diffusivity.
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Envejecimiento/patología , Encéfalo/patología , Síndrome de Creutzfeldt-Jakob/patología , Imagen de Difusión Tensora/métodos , Sustancia Gris/patología , Interpretación de Imagen Asistida por Computador/métodos , Algoritmos , Síndrome de Creutzfeldt-Jakob/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
In patients with temporal lobe epilepsy (TLE), assessment of language lateralization is important as anterior temporal lobectomy may lead to language impairments. Despite the widespread use of fMRI, evidence of its usefulness in predicting postsurgical language performance is scant. We investigated whether preoperative functional lateralization is related to the preoperative language performance, peri-ictal aphasia, and can predict language outcome one year post-surgery. We studied a total of 72 TLE patients (42 left, 30 right), by using three fMRI tasks: Naming, Verb Generation and Fluency. Functional lateralization indices were analyzed with neuropsychological scores and presence of peri-ictal aphasia. The key findings are:1)Both left and right TLE patients show decreased left lateralization compared to controls.2)Lateralization correlates with language performance before surgery. In left TLE, decreased left lateralization correlates with better fluency performance. In right TLE, increased left lateralization during the Naming task correlates with better naming.3)Left lateralization correlates with peri-ictal aphasia in left TLE patients.4)Lateralization correlates with language performance after surgery. In a subgroup of left TLE who underwent surgery (17 left), decreased left lateralization is predictive of better naming performance at 6 and 12 months after surgery. The present study highlights the clinical relevance of fMRI language lateralization in TLE, especially to predict language outcome one year post-surgery. We also underline the importance of using fMRI tasks eliciting frontal and anterior temporal activations, when studying left and right TLE patients.
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Innovative luminescent nanomaterials, termed upconversion nanoparticles (UCNPs), have demonstrated considerable promise as molecular probes for high-contrast optical imaging in cells and small animals. The feasibility study of optical diagnostics in humans is reported here based on experimental and theoretical modeling of optical imaging of an UCNP-labeled breast cancer lesion. UCNPs synthesized in-house were surface-capped with an amphiphilic polymer to achieve good colloidal stability in aqueous buffer solutions. The scFv4D5 mini-antibodies were grafted onto the UCNPs via a high-affinity molecular linker barstar:barnase (Bs:Bn) to allow their specific binding to the human epidermal growth factor receptor HER2/neu, which is overexpressed in human breast adenocarcinoma cells SK-BR-3. UCNP-Bs:Bn-scFv4D5 biocomplexes exhibited high-specific immobilization on the SK-BR-3 cells with the optical contrast as high as 10:1 benchmarked against a negative control cell line. Breast cancer optical diagnostics was experimentally modeled by means of epi-luminescence imaging of a monolayer of the UCNP-labeled SK-BR-3 cells buried under a breast tissue mimicking optical phantom. The experimental results were analyzed theoretically and projected to in vivo detection of early-stage breast cancer. The model predicts that the UCNP-assisted cancer detection is feasible up to 4 mm in tissue depth, showing considerable potential for diagnostic and image-guided surgery applications.
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Neoplasias de la Mama/patología , Sondas Moleculares/química , Nanopartículas/química , Imagen Óptica/métodos , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Animales , Anticuerpos Monoclonales , Neoplasias de la Mama/metabolismo , Células CHO , Proteínas Portadoras/química , Línea Celular Tumoral , Cricetinae , Cricetulus , Estudios de Factibilidad , Femenino , Humanos , Inmunoglobulinas/química , Sustancias Luminiscentes/química , Modelos Biológicos , Sondas Moleculares/metabolismo , Fantasmas de Imagen , Receptor ErbB-2/metabolismoRESUMEN
AIM: The purpose of this study was to investigate the disease-free time (DFT) and overall survival (OS) of patients with intermediate or high-risk cutaneous melanoma who were treated with conventional surgery alone, and to compare them with that of a second group of patients who were treated with surgery and SLN biopsy. METHODS: A retrospective, single-centre study was performed at the Department of Dermatology of the "M. Bufalini" Hospital, Cesena, Italy based on data collected between January 1990 and December 2007. A total of 757 consecutive patients with stage I-II melanoma were identified: the former group (control group), treated with conventional surgery, was composed of 224 patients; the latter, treated with surgery and SLN biopsy (SLN biopsy group), was formed of 529 patients. RESULTS: The 5-year disease free time (DFT) rate, estimated with Kaplan-Meyer, was 73.9% (95% CI: 67.5-79.2) in the control group, and 82.2% (95% CI: 78.6-85.3) in the SLN biopsy group. Although the DFT rate was significantly higher in the SLN group than in the control group in univariate analyses (P=0.004), this gain was lost in multivariate analysis (P=0.2). The 5-year overall survival (OS) rate was 88.4% (95% CI: 83.2-92.1) for the control group, and 87.9% (95% CI: 84.6-90.4) for the SLN biopsy group. Statistical comparison of specific OS was not statistically significant (P=0.93). CONCLUSION: On the basis of our follow-up data, we found that patients who underwent SLN biopsy technique experienced a reduction in the proportion of lymph nodal relapse, but DFT and OS were statistically equivalent between the two groups.
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Melanoma/patología , Melanoma/cirugía , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/secundario , Neoplasias Cutáneas/cirugía , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Italia , Metástasis Linfática , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Neoplasias Cutáneas/mortalidad , Tasa de SupervivenciaRESUMEN
BACKGROUND: Microbial air monitoring in operating theatres has been a subject of interest and debate. No generally accepted sampling methods and threshold values are available. AIM: To assess microbial air contamination in empty and working conventionally ventilated operating theatres over a three-year period at the University Hospital of Parma, Italy. METHODS: Air sampling was performed in 29 operating theatres. Both active and passive sampling methods were used to assess bacterial and fungal contamination. FINDINGS: In empty theatres, median bacterial values of 12 colony-forming units (cfu)/m(3) [interquartile range (IQR) 4-32] and 1 index of microbial air contamination (IMA) (IQR 0-3) were recorded. In working theatres, these values increased significantly (P < 0.001) to 80 cfu/m(3) (IQR 42-176) and 7 IMA (IQR 4-13). Maximum recorded values were 166 cfu/m(3) and 8 IMA for empty theatres, and 798 cfu/m(3) and 42 IMA for working theatres. Combining active and passive samplings, fungi were isolated in 39.13% of samples collected in empty theatres and 56.95% of samples collected in working theatres. Over the three-year study period, bacterial contamination decreased in both empty and working theatres, and the percentage of samples devoid of fungi increased. In working theatres, a significant correlation was found between the bacterial contamination values assessed using passive and active sampling methods (P < 0.001). CONCLUSION: Microbiological monitoring is a useful tool for assessment of the contamination of operating theatres in order to improve air quality.
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Microbiología del Aire , Bacterias/aislamiento & purificación , Monitoreo del Ambiente/métodos , Hongos/aislamiento & purificación , Quirófanos , Recuento de Colonia Microbiana , Hospitales Universitarios , ItaliaRESUMEN
INTRODUCTION: Antenatal day care units have been experienced as an alternative to inpatient care for women with pregnancy complications including hypertensive disorders. OBJECTIVES: To assess the outcomes of outpatient management in women with gestational hypertension and mild preeclampsia and compare them to inpatient management. METHODS: Perinatal records of 294 patients (OUT group) attending the obstetric outpatient clinic were reviewed and compared with records of 398 women (IN group) attending the obstetric unit of the same tertiary referral center. The patients were divided as: GH, gestational hypertension (OUT: 194; IN: 244), GH with Intrauterine Growth Restriction (OUT: 52; IN: 78) and PE, mild preeclampsia (OUT: 48; IN: 76). The groups were comparable for age, parity, body mass index and gestational age at enrollment. RESULTS: When compared with patients treated in hospital, GH OUT women showed a higher gestational age at delivery (38±1.7 vs 35.5±2.3 weeks; p<0.001), longer time to delivery (62.0±4.8 vs 31.3±5.4days; p<0.001), higher birthweight (3251±389 vs 2271±759.1g; p<0.001), and a lower admission to neonatal intensive care unit (21.3% vs 0%; p<0.001) (hospitalization rate: 25%). Similarly, Mild PE women treated as out patient showed later gestational age at delivery (37±1.2 vs 34.4±1.7weeks), longer time to delivery (55.4±6.9 vs 35.3±4.5days), higher birthweight (3168±363 vs 2196±685.17g), and a lower admission to NICU (15.6% vs 35.5%) (hospitalization rate: 55.6%), than the inpatient controls. In the gestational hypertension with IUGR no significant differences were observed between out- and in-patient management. CONCLUSION: Women attending day care units have better or comparable perinatal outcomes than inpatients. Ambulatory management at a day-care unit is an option for monitoring and following up women with mild gestational hypertension or preeclampsia remote from term. Hospitalization remains an absolute indication if worsening of preeclampsia is diagnosed.
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Hippocampal damage, by DTI or MR volumetry, and PET hypoperfusion of precuneus/posterior cingulate cortex (PC/PCC) were proposed as biomarkers of conversion from preclinical (MCI) to clinical stage of Alzheimer's disease (AD). This study evaluated structural damage, by DTI and MR volumetry, of hippocampi and tracts connecting hippocampus to PC/PCC (hipp-PC/PCC) in 10 AD, 10 MCI, and 18 healthy controls (CTRL). Normalized volumes, mean diffusivity (MD), and fractional anisotropy (FA) were obtained for grey matter (GM), white matter (WM), hippocampi, PC/PCC, and hipp-PC/PCC tracts. In hippocampi and hipp-PC/PCC tracts, decreased volumes and increased MD were found in AD versus CTRL (P < .001). The same results with lower significance (P < .05) were found in MCI versus CTRL. Verbal memory correlated (P < .05) in AD with left hippocampal and hipp-PC/PCC tract MD, and in MCI with FA of total WM. Both DTI and MR volumetry of hippocampi and hipp-PC/PCC tracts detect early signs of AD in MCI patients.
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BACKGROUND: Diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) MRI have high sensitivity and specificity for Creutzfeldt-Jakob disease (CJD). No studies, however, have demonstrated how MRI can distinguish CJD from nonprion causes of rapidly progressive dementia (npRPD). We sought to determine the diagnostic accuracy of MRI for CJD compared to a cohort of npRPD subjects. METHODS: Two neuroradiologists blinded to diagnosis assessed DWI and FLAIR images in 90 patients with npRPD (n = 29) or prion disease (sporadic CJD [sCJD], n = 48, or genetic prion disease [familial CJD, n = 6, and Gerstmann-Sträussler-Scheinker, n = 7]). Thirty-one gray matter regions per hemisphere were assessed for abnormal hyperintensities. The likelihood of CJD was assessed using our previously published criteria. RESULTS: Gray matter hyperintensities (DWI > FLAIR) were found in all sCJD cases, with certain regions preferentially involved, but never only in limbic regions, and rarely in the precentral gyrus. In all sCJD cases with basal ganglia or thalamic DWI hyperintensities, there was associated restricted diffusion (apparent diffusion coefficient [ADC] map). This restricted diffusion, however, was not seen in any npRPD cases, in whom isolated limbic hyperintensities (FLAIR > DWI) were common. One reader's sensitivity and specificity for sCJD was 94% and 100%, respectively, the other's was 92% and 72%. After consensus review, the readers' combined MRI sensitivity and specificity for sCJD was 96% and 93%, respectively. Familial CJD had overlapping MRI features with sCJD. CONCLUSIONS: The pattern of FLAIR/DWI hyperintensity and restricted diffusion can differentiate sCJD from other RPDs with a high sensitivity and specificity. MRI with DWI and ADC should be included in sCJD diagnostic criteria. New sCJD MRI criteria are proposed.
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Síndrome de Creutzfeldt-Jakob/diagnóstico , Demencia/diagnóstico , Encéfalo/patología , Estudios de Cohortes , Síndrome de Creutzfeldt-Jakob/patología , Demencia/patología , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética , Enfermedad de Gerstmann-Straussler-Scheinker/diagnóstico , Enfermedad de Gerstmann-Straussler-Scheinker/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Sistema Límbico/patología , Neocórtex/patología , Variaciones Dependientes del Observador , Enfermedades por Prión/patología , Estudios RetrospectivosRESUMEN
Optical sensing polymer particles with tailored semiconductor nanocrystal (QD) loading are prepared by layer-by-layer deposition technique (LbL). Polyacrolein particles of 1.2 µm diameter are used as solid support for deposition of hydrophilic CdSe/ZnS nanocrystal/polyelectrolyte multilayers formed by electrostatic interactions. The pH-dependent fluorescence of QDs and pH-dependent conformations of polyelectrolytes, which likely passivate the surface state of nanocrystals, allow a creation of both mono- and multiplex coded polymer particles with pH-dependent fluorescence intensity. Bovine serum albumin (BSA) as outermost layer makes it possible to design the optical sensing polymer particles with reversibly responded fluorescence at pH variations. The fluorescence of such polymer particles with BSA outer layer is sensitive to copper(II) ion while the fluorescence of these particles is practically insensitive to the other divalent cations (Zn(2+), Ca(2+), Ba(2+), Co(2+), Mg(2+)). The detection limit of Cu(2+) is about 15 nM. Adaptation of LbL method to prepare QD-labeled polymer particles with enhanced complexity (e.g. several types of QDs, multiple biofunctionality) is expected to open new opportunities in biotechnological applications.
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Acroleína/química , Nanopartículas/química , Polímeros/química , Puntos Cuánticos , Albúmina Sérica Bovina/química , Animales , Bovinos , Concentración de Iones de Hidrógeno , Proteínas Inmovilizadas/química , Modelos Biológicos , Espectrometría de Fluorescencia , Propiedades de SuperficieRESUMEN
Reversible changes of the height of a polymer brush containing phenylboronic acid were studied. The polymer brush thickness underwent reversible changes of 0.5-1 nm, in response to the changes in composition of the contacting aqueous phase from deionized water to bicarbonate buffer and vice versa, apparently due to the conformational transition of the weak polyelectrolyte to the more extended electrically charged state. Adsorption of mucin glycoprotein to the polymer brush took place due to boronate/sugar interactions between the glycoprotein and the graft copolymer and resulted in further increase of the brush height by ca. 1.5 nm, as observed by means of spectral correlation spectroscopy and ellipsometry.
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Ácidos Borónicos/química , Conformación Molecular , Mucinas/metabolismo , Polímeros/química , Polímeros/metabolismo , Acrilatos/química , Adsorción , Compuestos Azo/química , Microscopía de Fuerza Atómica , Polímeros/síntesis química , Análisis Espectral , ViscosidadRESUMEN
Structural Equation Modelling analysis of three longitudinal er-fMRI sessions was used to test the impact of phonological training and of the generalization process on the pattern of brain connectivity during overt picture naming in two chronic anomic patients. Phonological training yielded a positive effect on the trained material. Six months after the training, a generalization of the positive impact on the untrained items was also observed. Connectivity analysis showed that training and generalization effects shared paralleled cortical patterns of functional integration. These findings may represent the neurophysiological correlate of the training-induced cognitive strategies for the compensation of anomia.
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Anomia/fisiopatología , Anomia/terapia , Encéfalo/fisiopatología , Terapia del Lenguaje/métodos , Fonética , Enseñanza/métodos , Afasia/fisiopatología , Afasia/rehabilitación , Lesiones Encefálicas/complicaciones , Simulación por Computador , Humanos , Lenguaje , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Neurológicos , Red Nerviosa/fisiopatología , Vías Nerviosas/fisiopatología , Evaluación de Resultado en la Atención de Salud , Habla/fisiología , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento , Conducta Verbal/fisiología , Adulto JovenAsunto(s)
Demencia/patología , Imagen por Resonancia Magnética/estadística & datos numéricos , Imagen por Resonancia Magnética/normas , Enfermedad de Pick/patología , Adulto , Anciano , Anciano de 80 o más Años , Atrofia , Humanos , Hidrocéfalo Normotenso/patología , Persona de Mediana Edad , Neurorradiografía/normas , Variaciones Dependientes del Observador , Estudios RetrospectivosRESUMEN
Vocabulary acquisition is such a major aspect of language learning in children, but also in adults when learning a foreign language, that a dedicated vocabulary learning device may exist within the language organ. To identify the relevant brain systems, we performed regional cerebral blood flow measurements in normal subjects while they were learning a list of neologisms or a list of word-nonword pairs. Structures implicated in phonological short-term memory (Broca's area, left temporo-parietal junction) were steadily activated during nonwords learning, while the left temporal lobe neocortical and paralimbic structures (parahippocampal region), associated with long-term memory, contributed to learning in a time-dependent manner, with maximal activation at the beginning of the process. The neural system specifically activated when learning new vocabulary was strongly lateralized to the left hemisphere. This evidence refines current models of memory function and supports theories which emphasise the importance of phonological competence in hemispheric dominance for language.
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Encéfalo/fisiología , Potenciales Evocados/fisiología , Aprendizaje/fisiología , Recuerdo Mental/fisiología , Fonética , Tomografía de Emisión de Positrones/métodos , Vocabulario , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Humanos , Masculino , Adulto JovenRESUMEN
The aim of this study was to evaluate the efficacy of a mobile laminar airflow (LAF) unit in reducing bacterial contamination at the surgical area in an operating theatre supplied with turbulent air ventilation. Bacterial sedimentation was evaluated during 76 clean urological laparotomies; in 34 of these, a mobile LAF unit was added. During each operation, settle plates were placed at four points in the operating theatre (one at the patient area and three at the perimeter), a nitrocellulose membrane was placed on the instrument table and an additional membrane near the wound. During four operations, particle counting was performed to detect particles > or =0.5 microm. Mean bacterial sedimentation on the nitrocellulose membrane on the instrument table was 2730 cfu/m(2)/h under standard ventilation conditions, whereas it decreased significantly to a mean of 305 cfu/m(2)/h when the LAF unit was used, i.e. within the suggested limit for ultraclean operating theatres (P=0.0001). The membrane near the wound showed a bacterial sedimentation of 4031 cfu/m(2)/h without the LAF unit and 1608 cfu/m(2)/h with the unit (P=0.0001). Particle counts also showed a reduction when the LAF unit was used. No significant difference was found at the four points in the operating theatre between samplings performed with, and without, the LAF unit. Use of a mobile LAF unit with turbulent air ventilation can reduce bacterial contamination at the surgical area in high-risk operations (e.g. prosthesis implant).
Asunto(s)
Infección Hospitalaria/prevención & control , Ambiente Controlado , Quirófanos , Infección de la Herida Quirúrgica/prevención & control , Recuento de Colonia Microbiana , Monitoreo del Ambiente/métodos , Humanos , Material Particulado/análisisRESUMEN
The purpose of the study was to evaluate the Von Restorff effect in normal ageing and in Alzheimer's disease (AD). A shortened paradigm was administered to three groups of subjects: young volunteers, elderly volunteers and patients with early-stage AD (MMSE>20). Each subject was presented with 25 lists of 10 words each, the target word appearing in double font size. A free recall phase followed the presentation of each list; after completion of the battery, a size recognition test was administered and subjects were inquired regarding the strategy employed and perception of target words. The total number of recalled words differed significantly among the three groups (young volunteers 144.4+/-38.6, elderly volunteers 86.5+/-17.6, patients 44.2+/-14.6). A significant difference in percentage of recall was found between target and non-target words in young (60.0+/-13.8% vs. 45.7%+/-15.0%, p<0.001) and in elderly (31.2+/-11.4% vs. 20.2+/-6.9%, p<0.001) volunteers, but not in patients (10.7+/-6.9% vs. 11.8+/-7.3%). The present study highlights that the Von Restorff effect can be detected in healthy elderly subjects, and that it is significantly reduced in patients in the early stage of AD. On the basis of the findings of the present study it is not possible to disentangle the contribution of visual-perceptual and encoding impairment, both of them potentially contributing to the observed reduction.