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1.
Rev Sci Instrum ; 91(5): 053301, 2020 May 01.
Article in English | MEDLINE | ID: mdl-32486736

ABSTRACT

This work describes the new facility for applied nuclear physics at the University of Sao Paulo, mainly for irradiation of electronic devices. It is a setup composed of a quadrupole doublet for beam focusing/defocusing plus multiple scattering through gold foils to produce low intensity, large-area, and high-uniformity heavy-ion beams from 1H to 107Ag. Beam intensities can be easily adjusted from 102 particles cm2/s to hundreds of nA for an area as large as 2.0 cm2 and uniformity better than 90%. Its irradiation chamber has a high-precision motorized stage, and the system is controlled by a LabViewTM environment, allowing measurement automation. Design considerations and examples of use are presented.

2.
G Ital Dermatol Venereol ; 146(2): 95-101, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21505395

ABSTRACT

AIM: We aimed to test a new teledermatologic method that permits to match a high level of diagnostic accuracy, comparable with or higher to that of the "Store and Forward" method, with the highest handiness, comparable to that achievable with a video call, without suffering from the limitations of the two methods. METHODS: We used latest-generation cell phones with a HSDPA network broad-band internet access system for video calling and for sending via e-mail high-definition images, chosen by the specialist-at-a-distance during the video call, in times comparable to those achievable with fixed-wired access systems. We tested the diagnostic reliability, the compliance and the efficacy of the method. RESULTS: We found a significant concordance both between direct and via video call description of the objective signs and between direct and on high definition image description. The Spearman Rank showed a higher correlation between direct observation and high definition image observation than between direct and via video call observation: this last finding matched the experimenters' subjective experience. The compliance was positive and the efficacy comparable with the ambulatorial follow-up. CONCLUSION: In conclusion, the "Phone and Mail" method can be seen as being capable of joining together the necessary diagnostic precision and effectiveness with a high degree of practicality and simplicity, thanks to the ease of use of the cell phone, within the reach of everybody, to the ubiquity of its utilization, to the allowed rapidity of diagnosis, practically in real time, and to the low cost of the system.


Subject(s)
Cell Phone , Dermatology , Electronic Mail , Mental Disorders/diagnosis , Patient Satisfaction , Skin Diseases/diagnosis , Telemedicine , Follow-Up Studies , Humans , Mental Disorders/complications , Mental Disorders/therapy , Reproducibility of Results , Skin Diseases/complications , Skin Diseases/therapy , Surveys and Questionnaires , Telemedicine/methods , Treatment Outcome
3.
Arch Ital Biol ; 146(2): 83-105, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18822797

ABSTRACT

This work investigates the neural correlates of single-letter reading by combining event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI), thus exploiting their complementary spatiotemporal resolutions. Three externally-paced reading tasks were administered with an event-related design: passive observation of letters and symbols and active reading aloud of letters. ERP and fMRI data were separately recorded from 8 healthy adults during the same experimental conditions. Due to the presence of artifacts in the EEG signals, two subjects were discarded from further analysis. Independent Component Analysis was applied to ERPs, after dimensionality reduction by Principal Component Analysis: some independent components were clearly related to specific reading functions and the associated current density distributions in the brain were estimated with Low Resolution Electromagnetic Tomography Analysis method (LORETA). The impulse hemodynamic response function was modeled as a linear combination of linear B-spline functions and fMRI statistical analysis was performed by multiple linear regression. fMRI and LORETA maps were superimposed in order to identify the overlapping activations and the activated regions specifically revealed by each modality. The results showed the existence of neuronal networks functionally specific for letter processing and for explicit verbal-motor articulation, including the temporo-parietal and frontal regions. Overlap between fMRI and LORETA results was observed in the inferior temporal-middle occipital gyrus, suggesting that this area has a crucial and multifunctional role for linguistic and reading processes, likely because its spatial location and strong interconnection with the main visual and auditory sensory systems may have favored its specialization in grapheme-phoneme matching.


Subject(s)
Brain/physiology , Evoked Potentials/physiology , Language , Pattern Recognition, Visual/physiology , Reading , Verbal Behavior/physiology , Adult , Brain Mapping , Electroencephalography , Female , Functional Laterality/physiology , Humans , Magnetic Resonance Imaging , Male , Occipital Lobe/anatomy & histology , Occipital Lobe/physiology , Signal Processing, Computer-Assisted , Temporal Lobe/anatomy & histology , Temporal Lobe/physiology , Time Factors
4.
Arch Ital Biol ; 146(3-4): 133-46, 2008 Sep.
Article in English | MEDLINE | ID: mdl-19378878

ABSTRACT

In sighted individuals, both the visual and tactile version of the same spatial working memory task elicited neural responses in the dorsal "where" cortical pathway (Ricciardi et al., 2006). Whether the neural response during the tactile working memory task is due to visually-based spatial imagery or rather reflects a more abstract, supramodal organization of the dorsal cortical pathway remains to be determined. To understand the role of visual experience on the functional organization of the dorsal cortical stream, using functional magnetic resonance imaging (fMRI) here we examined brain response in four individuals with congenital or early blindness and no visual recollection, while they performed the same tactile spatial working memory task, a one-back recognition of 2D and 3D matrices. The blind subjects showed a significant activation in bilateral posterior parietal cortex, dorsolateral and inferior prefrontal areas, precuneus, lateral occipital cortex, and cerebellum. Thus, dorsal occipito-parietal areas are involved in mental imagery dealing with spatial components in subjects without prior visual experience and in response to a non-visual task. These data indicate that recruitment of the dorsal cortical pathway in response to the tactile spatial working memory task is not mediated by visually-based imagery and that visual experience is not a prerequisite for the development of a more abstract functional organization of the dorsal stream. These findings, along with previous data indicating a similar supramodal functional organization within the ventral cortical pathway and the motion processing brain regions, may contribute to explain how individuals who are born deprived of sight are able to interact effectively with the surrounding world.


Subject(s)
Blindness , Cerebral Cortex/physiology , Memory/physiology , Touch Perception/physiology , Adult , Blindness/congenital , Blindness/physiopathology , Cerebral Cortex/anatomy & histology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Psychomotor Performance/physiology , Visual Pathways/physiology , Young Adult
5.
Alcohol Alcohol ; 41(3): 336-40, 2006.
Article in English | MEDLINE | ID: mdl-16549403

ABSTRACT

AIMS: We investigated drinking habits, and heavy and problem drinking prevalence in a sample of individuals attending the consulting rooms of local General Practitioners in three Italian villages. METHODS: The samples were selected to be representative of the entire population of the three villages. Information on alcohol-drinking patterns was collected using a questionnaire that included a masked form of the CAGE rating scale. According to the frequency of alcohol intake, subjects were grouped in three categories: abstainers, occasional drinkers, and daily drinkers. In agreement with WHO guidelines, 40 g/day for males and 20 g/day for females were taken as cut-off for 'heavy drinking' and consumptions of > 80 g/day for males and 40 g/day for females were used to define 'problem drinking'. RESULTS: A total of 2972 individuals were included in the survey (19% of the population). Of these, 44% were abstinent, 20% occasional drinkers, and 36% daily drinkers. Daily drinking was found to be more common in males than in females but heavy drinking was significantly higher in females compared with males (P > or = 0.0001). The problem drinkers were 12% of the entire population and the CAGE-positive subjects (> or = 2 positive answers) were 3.5%. CONCLUSIONS: Our data indicate that alcohol drinking is widely diffused in the three communities. A large layer of the population drinks above the WHO-established cut-off. The incidence of heavy and problem drinking seems to have significant gender and regional differences that are important to consider when planning effective prevention programmes.


Subject(s)
Alcohol Drinking/epidemiology , Alcoholism/epidemiology , Adolescent , Adult , Age Factors , Aged , Female , Humans , Italy/epidemiology , Male , Middle Aged , Sex Factors , Surveys and Questionnaires , Wine
6.
Arch Ital Biol ; 143(1): 65-79, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15844669

ABSTRACT

Sleep disturbances are found in the course of most dementing syndromes. We report a longitudinal polysomnographic and 18FDG-PET study in a 38-year-old male with FTDP17 carrying the Tau gene mutation G389R. All-night sleep EEG and wake cerebral glucose metabolism at rest (eyes/ears covered) of the preceding day were studied twice, eight months (Night 1; PET 1) and sixteen months (Night 2; PET 2) after the initial neurological evaluation. The Night 1 study showed sleep fragmentation associated to a short REM latency and a severe reduction of slow wave sleep, with relatively preserved NREM-REM sleep cycles; daytime PET 1 revealed severe cerebral glucose metabolic reductions in frontal and temporal areas, with relative preservation of remaining cortical regions and subcortical structures. On Night 2, the total sleep time was less than 5 hours, delta sleep and REM latency remained shortened and only two sleep cycles could be identified; daytime PET 2 exam revealed a greater cortical metabolic impairment and an involvement of subcortical brain regions as compared to PET 1. Post-mortem neuropathological data showed severe neuronal loss, spongiosis and gliosis that were mostly marked in cortical layers I, II, V and VI. In vivo, neurometabolic and post-mortem neuropathological data are consistent with and indicative of a severe dysfunction of intra- and trans-hemispheric regional connectivity and of cortico-thalamic circuits. These findings suggest that the decreased cortical and subcortical connectivity may have been the main pathophysiological mechanism responsible for delta sleep reduction and the cognitive decline.


Subject(s)
Brain/physiopathology , Pick Disease of the Brain/physiopathology , Sleep Wake Disorders/physiopathology , Sleep, REM/genetics , Sleep/genetics , tau Proteins/genetics , Adult , Brain/diagnostic imaging , Brain/pathology , Disease Progression , Fatal Outcome , Humans , Longitudinal Studies , Male , Nerve Degeneration/metabolism , Nerve Degeneration/pathology , Nerve Degeneration/physiopathology , Neural Pathways/metabolism , Neural Pathways/pathology , Neural Pathways/physiopathology , Pick Disease of the Brain/diagnostic imaging , Pick Disease of the Brain/genetics , Polysomnography , Positron-Emission Tomography , Sleep Wake Disorders/diagnostic imaging , Sleep Wake Disorders/genetics
7.
Arch Ital Biol ; 142(2): 77-85, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15248563

ABSTRACT

The aim of the experiment was to study whether the activity of the primary sensory-motor (S1/M1), supplementary motor (SMA) and pre-motor (PMA) areas during fingers movement is modulated by hypnotic susceptibility and hypnosis. Cortical activity was studied through functional Magnetic Resonance Imaging (fMRI) during a finger-to-thumb opposition task in awake (Highs) and hypnotized highly susceptible (H-Highs) as well as in awake non susceptible subjects (Lows). Results did not show any significant difference in sensory-motor areas activation between Highs and Lows (trait effect) and between Highs and H-Highs (state effect). The activation in 3 subjects among Highs and only 1 among Lows (out of 5) of the caudal S1, receiving the most part of the cutaneous input, appears noteworthy and prompts further investigation on possible hypnotizability-related differences in sensory-motor integration.


Subject(s)
Hypnosis , Motor Cortex/physiology , Movement/physiology , Somatosensory Cortex/physiology , Adult , Attention/physiology , Brain Mapping , Cognition/physiology , Consciousness/physiology , Female , Fingers/innervation , Fingers/physiology , Functional Laterality/physiology , Humans , Illusions/physiology , Magnetic Resonance Imaging , Male , Motor Cortex/anatomy & histology , Psychomotor Performance/physiology , Somatosensory Cortex/anatomy & histology , Touch/physiology
8.
Arch Ital Biol ; 142(1): 1-9, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15143619

ABSTRACT

The present fMRI study compares regional distribution of the cortical activity during the execution of unilateral hand movements (finger-to-thumb opposition) preceded or not by their motor simulation (S + E and E condition, respectively). The results show that, overall, the number and the spatial distribution of activated voxels are both increased in the S + E with respect to the E condition. The motor performance preceded by mental rehearsal is related to selective increase of the cortical activity. Among the motor areas that are found active during the simple motor execution a significant enhancement of functional activation during the S + E condition ipsilateral primary motor regions (M1). The activity increase may be accounted by a sort of neural recruiting that is made possible by the overlapping of cortical networks involved in both motor output and motor imagery. The beneficial effects of "mental practice" on the physical performance may rely to the close temporal association between motor rehearsal and actual performance.


Subject(s)
Hand/physiology , Imagination/physiology , Motor Cortex/physiology , Movement/physiology , Psychomotor Performance/physiology , Adult , Brain Mapping , Cognition/physiology , Female , Fingers/innervation , Fingers/physiology , Functional Laterality/physiology , Hand/innervation , Humans , Magnetic Resonance Imaging , Motor Cortex/anatomy & histology , Thumb/innervation , Thumb/physiology
9.
J Psychiatr Res ; 34(4-5): 293-300, 2000.
Article in English | MEDLINE | ID: mdl-11104841

ABSTRACT

GABAergic hypnotics are known to depress non-rapid eye movement delta and rapid eye movements and to stimulate non-rapid eye movement sigma (spindles) and beta EEG. This study addressed the question of whether the magnitudes of these effects are significantly correlated. Data were from a study in 16 normal subjects whose sleep was recorded for five nights under placebo and for three nights each under zolpidem (10 mg), triazolam (0.25 mg) and temazepam (30 mg). EEG was analyzed with both period-amplitude and power spectral (FFT) analysis. The magnitudes of the EEG and eye movement density responses were not significantly correlated for any of the three drugs. It is therefore unlikely that sleep responses to GABAergic drugs can be explained by the common cellular action (increased chloride conductance) of these drugs. We suggest that the sleep EEG responses are manifestations of complex (but consistent) interactions of excitation and inhibition in large brain systems although certain aspects of these responses (e.g. the different time courses of delta vs sigma and eye movement responses) may reflect molecular adaptations. A separate observation in this study was the strong traitlike characteristics of the sleep variables studied. These variables were highly correlated across nights of baseline sleep; in addition, individual differences in baseline sleep were significantly retained on the third night of temazepam administration.


Subject(s)
Electroencephalography/drug effects , GABA Agonists/pharmacology , Hypnotics and Sedatives/pharmacology , Pyridines/pharmacology , Sleep, REM/drug effects , Temazepam/pharmacology , Triazolam/pharmacology , Adult , Electronic Data Processing , Female , Humans , Male , Reproducibility of Results , Zolpidem
10.
Am J Psychiatry ; 157(11): 1772-81, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11058474

ABSTRACT

OBJECTIVE: Neurodegenerative or traumatic lesions of the frontal lobes often lead to abnormally aggressive behavior. The authors hypothesized that the imaginal evoking of scenarios involving aggressive behavior would be associated with a modulation of the functional activity in the human frontal cortex. METHOD: Regional cerebral blood flow (rCBF) determinations by positron emission tomography and psychophysiological measures of emotional responsivity were obtained in a group of 15 young healthy volunteers with good visual imagery abilities and no history of abnormal behavior while they imagined the same scenario with four variations involving emotionally neutral behavior and aggressive behavior. RESULTS: Compared to the imagined neutral scenario, the imagined scenarios involving aggressive behavior were associated with significant emotional reactivity and rCBF reductions in the ventromedial prefrontal cortex, suggesting that a functional deactivation of this cortical area occurs when individuals respond to the eliciting of imagined aggressive behavior. CONCLUSIONS: These results in healthy subjects further expand previous findings from animal and human studies by providing an in vivo functional demonstration of the involvement of the orbitofrontal cortex in the expression of aggressive behavior. They are also consistent with the hypothesis that a functional alteration of this cortical region may be present in individuals with pathological aggressive behavior.


Subject(s)
Aggression/physiology , Frontal Lobe/physiology , Imagination/physiology , Models, Neurological , Tomography, Emission-Computed/statistics & numerical data , Visual Perception/physiology , Adult , Emotions/physiology , Female , Frontal Lobe/blood supply , Frontal Lobe/diagnostic imaging , Humans , Male , Prefrontal Cortex/blood supply , Prefrontal Cortex/physiology , Regional Blood Flow
12.
Int Clin Psychopharmacol ; 15(1): 29-34, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10836283

ABSTRACT

This was a 6-week, double-blind, randomized trial of the efficacy and tolerability of venlafaxine and fluoxetine in 109 patients with major depression and melancholia. Hospitalized and day care patients with DSM-IV major depression and melancholia and a baseline Montgomery-Asberg Depression Rating Scale (MADRS) score of > or = 25 were eligible. The doses were venlafaxine 75 mg/day or fluoxetine 20 mg/day from days 1-4, venlafaxine 150 mg/day or fluoxetine 40 mg/day from days 5-10, and venlafaxine 225 mg/day or fluoxetine 60 mg/day from days 11-42. The intention-to-treat analyses included 55 patients on venlafaxine and 54 on fluoxetine. At the final evaluation, 70% of patients with venlafaxine and 66% with fluoxetine had > or = 50% reduction in the MADRS score, and 70% with venlafaxine and 62% with fluoxetine had a Clinical Global Impression (CGI) score of 1 or 2. A CGI improvement score of 1 was observed in 51% of patients with venlafaxine and 32% with fluoxetine (P = 0.018). A final Hamilton Depression Rating Scale (HAM-D) score < 7 was attained in 41% of venlafaxine-treated and 36% of fluoxetine-treated patients. Overall, 22% of patients in each group discontinued therapy, but only 5% on venlafaxine and 9% on fluoxetine discontinued for adverse events. Nausea was reported in 5.5% of venlafaxine-treated patients and 14.8% of fluoxetine-treated patients. Venlafaxine was effective and well tolerated for treating inpatients with major depression and melancholia. Based on remission criteria (HAM-D < 7 or CGI of 1), venlafaxine was superior to fluoxetine.


Subject(s)
Antidepressive Agents, Second-Generation/therapeutic use , Cyclohexanols/therapeutic use , Depressive Disorder/drug therapy , Fluoxetine/therapeutic use , Adolescent , Adult , Antidepressive Agents, Second-Generation/adverse effects , Cyclohexanols/adverse effects , Depressive Disorder/psychology , Double-Blind Method , Female , Fluoxetine/adverse effects , Hospitalization , Humans , Male , Middle Aged , Psychiatric Status Rating Scales , Recurrence , Venlafaxine Hydrochloride
13.
Int J Psychophysiol ; 37(1): 87-98, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10828377

ABSTRACT

Alzheimer's disease, the most common form of dementia in the elderly, is characterized by the progressive, global and irreversible deterioration of cognitive abilities. The development of positron emission tomography (PET) methodologies has made it possible to study the in vivo brain metabolic correlates of human cognitive and behavioral functions. Moreover, as PET scan examinations can be repeated, the progression of the neuropathological process and its relation to cognitive dysfunction can be followed over time. In an effort to understand the changes in neural function that precede and accompany onset of dementia and their relation to clinical manifestations, in the last several years, we have conducted clinical, neuropsychological and brain metabolic studies in groups of Alzheimer's disease patients at different stages of dementia severity or with distinct clinical pictures and in populations at risk for developing the disease. Here, we discuss the main findings and implications obtained from these studies.


Subject(s)
Alzheimer Disease/metabolism , Alzheimer Disease/psychology , Brain/metabolism , Cognition Disorders/metabolism , Tomography, Emission-Computed , Alzheimer Disease/diagnostic imaging , Cognition Disorders/diagnostic imaging , Dementia/psychology , Glucose/metabolism , Humans
14.
J Nucl Med ; 41(4): 575-83, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10768555

ABSTRACT

UNLABELLED: Alzheimer's disease is associated with reductions in resting-state brain metabolism, as measured by PET, progressing with dementia severity. The purpose of this study was to see to what extent brain regions with reduced resting-state metabolic rates in Alzheimer patients could be activated by a passive audiovisual stimulation test and to compare the result with activation in age-matched healthy volunteers. The extent of activation in Alzheimer's disease is considered to reflect the integrity of synaptic function, or inherent viability, and the potential responsiveness of the Alzheimer brain to drug therapy. METHODS: Regional cerebral metabolic rates for glucose (rCMRglc, in mg/ 100 g tissue/min) were measured in the resting state (eyes and ears covered) and during passive audiovisual stimulation (watching a movie) in 15 otherwise healthy Alzheimer patients of differing dementia severity (Mattis Dementia Rating Scale score, 23-128) and in 14 age-matched healthy volunteers (score, 141 +/- 3) using PET with 2 sequential injections of FDG. RESULTS: In the volunteers, audiovisual stimulation caused significant rCMRglc increases in visual and auditory cortical areas but significant decreases in frontal areas. In the mildly demented patients, rCMRglc responses were within 2 SDs of the mean in volunteers. However, the magnitude of the rCMRglc responses during stimulation declined significantly with dementia severity in the right occipitotemporal, right and left occipital association, and left calcarine cortical regions. CONCLUSION: Functional brain responsiveness, evaluated by a passive audiovisual stimulation paradigm with PET, is within normal limits in mildly demented Alzheimer patients but fails with worsening dementia severity. Declining responsiveness may account for the limited success of neurotransmitter replacement therapy in Alzheimer patients with moderate-to-severe dementia.


Subject(s)
Alzheimer Disease/diagnostic imaging , Brain/metabolism , Tomography, Emission-Computed , Acoustic Stimulation , Aged , Alzheimer Disease/physiopathology , Brain/diagnostic imaging , Case-Control Studies , Female , Fluorine Radioisotopes , Fluorodeoxyglucose F18 , Glucose/metabolism , Humans , Male , Photic Stimulation , Radiopharmaceuticals
15.
Clin Neurophysiol ; 111(3): 452-6, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10699406

ABSTRACT

OBJECTIVES: We report on a case of ESES/CSWS observed in a patient of 21 years and still persisting at the age of 25. Cases of ESES/CSWS have never been previously described in adult patients. ESES/CSWS is considered to be related to the degree of maturation of the central nervous system, and therefore strictly age-related. METHODS: Our case of ESES/CSWS was observed in a 2 1 year old woman referred for cognitive and behavioral disorders. She had previously had epileptic fits, but was seizure free at that time. The patient underwent a full-night polygraphic recording , which showed typical ESES/CSWS pattern, with a Spike-and-Wave Index >8 5%. Polysomnography was repeated 9 times in a 4 year follow-up, during which the ESES/CSWS condition persisted, despite the pharmacological treatments. The patient also underwent cerebral magnetic resonance imaging and fludeoxyglucose F 18 positron emission tomography (PET). RESULTS: The PET study revealed reduced metabolic activity within the lower gyrus of the right parietal lobe, but no significant difference between subcortical structures and cortical mantle was seen. MRI scans were normal. CONCLUSIONS: This observation suggests that ESES/CSWS might not always be an age-related condition. Sleep EEG recordings should always be performed in patients with behavioral disorders and a history of epileptic fits.


Subject(s)
Sleep/physiology , Status Epilepticus/physiopathology , Adult , Brain/diagnostic imaging , Brain/physiopathology , Female , Humans , Polysomnography , Status Epilepticus/diagnostic imaging , Tomography, Emission-Computed
16.
J Neuropathol Exp Neurol ; 58(12): 1207-26, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10604746

ABSTRACT

Exonic and intronic mutations in Tau cause familial neurodegenerative syndromes characterized by frontotemporal dementia and dysfunction of multiple cortical and subcortical circuits. Here we describe a G389R mutation in exon 13 of Tau. When 38 years old, the proband presented with progressive aphasia and memory disturbance, followed by apathy, indifference, and hyperphagia. Repeated magnetic resonance imaging showed the dramatic progression of cerebral atrophy. Positron emission tomography revealed marked glucose hypometabolism that was most severe in left frontal, temporal, and parietal cortical regions. Rigidity, pyramidal signs and profound dementia progressed until death at 43 years of age. A paternal uncle, who had died at 43 years of age, had presented with similar symptoms. The proband's brain showed numerous tau-immunoreactive Pick body-like inclusions in the neocortex and the fascia dentata of the hippocampus. In addition, large numbers of tau-positive filamentous inclusions were present in axons in the frontal, temporal, and parietal lobes. Immunoblot analysis of sarkosyl-insoluble tau showed 2 major bands of 60 and 64 kDa. Upon dephosphorylation, these bands resolved into 4 bands consisting of three- and four-repeat tau isoforms. Most isolated tau filaments were straight and resembled filaments found in Alzheimer disease and some frontotemporal dementias with tau mutations. A smaller number of twisted filaments was also observed. Biochemically, recombinant tau proteins with the G389R mutation showed a reduced ability to promote microtubule assembly, suggesting that this may be the primary effect of the mutation. Taken together, the present findings indicate that the G389R mutation in Tau can cause a dementing condition that closely resembles Pick's disease.


Subject(s)
Axons/metabolism , Inclusion Bodies/pathology , Mutation/physiology , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/pathology , tau Proteins/genetics , Adult , Brain/metabolism , Brain/pathology , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male , Medical Records , Microscopy, Electron , Microtubules/ultrastructure , Neurodegenerative Diseases/diagnosis , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/psychology , Pedigree , tau Proteins/metabolism
17.
Br J Psychiatry ; 174: 196-204, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10448443

ABSTRACT

BACKGROUND: In spite of intensive research, no causal anatomical lesion has been found in schizophrenia. It may instead be caused by malfunctioning circuits in the corollary discharge, feed forward (CD-FF) systems of thought. AIMS: To integrate with the CD-FF hypothesis recent data showing that subcortical motor systems participate in thinking. METHODS: We review CD-FF concepts in relation to recent evidence that 'motor' brain structures participate in cognitive processing. RESULTS: Malfunctioning of CD-FF systems that integrate thinking and consciousness could produce auditory hallucinations, delusions and disorganised thought. CONCLUSIONS: We hypothesise that the pathophysiology of schizophrenia lies in integrative circuits of basal ganglia, thalamus and frontal cortex. Fruitful research directions would include elucidation of CD-FF circuits at even higher brain levels, the behaviour of these circuits during dreaming, and their responses to late maturational events including synaptic elimination.


Subject(s)
Cognition Disorders/psychology , Consciousness , Psychomotor Disorders/psychology , Schizophrenic Psychology , Thinking , Hallucinations , Humans , Neural Pathways/physiopathology
18.
Cephalalgia ; 19(3): 159-64, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10234463

ABSTRACT

A multicenter study was carried out in 10 Italian Headache Centers to investigate the prevalence of psychosocial stress and psychiatric disorders listed by the IHS classification as the "most likely causative factors" of tension-type headache (TTH). Two hundred and seventeen TTH adult outpatients consecutively recruited underwent a structured psychiatric interview (CIDI-c). The assessment of psychosocial stress events was carried out using an ad hoc questionnaire. The psychiatric disorders that we included in the three psychiatric items of the fourth digit of the IHS classification were depressive disorders for the item depression, anxiety disorders for the item anxiety, and somatoform disorders for the item headache as a delusion or an idea. Diagnoses were made according to DSM-III-R criteria. At least one psychosocial stress event or a psychiatric disorder was detected in 84.8% of the patients. Prevalence of psychiatric comorbidity was 52.5% for anxiety, 36.4% for depression, and 21.7% for headache as a delusion or an idea. Psychosocial stress was found in 29.5% of the patients and did not differ between patients with and without psychiatric comorbidity. Generalized anxiety disorder (83.3%) and dysthymia (45.6%) were the most frequent disorders within their respective psychiatric group. The high prevalence of psychiatric disorders observed in this wide sample of patients emphasizes the need for a systematic investigation of psychiatric comorbidity aimed at a more comprehensive and appropriate clinical management of TTH patients.


Subject(s)
Stress, Psychological/psychology , Tension-Type Headache/psychology , Adult , Female , Humans , Italy , Male , Middle Aged , Psychiatric Status Rating Scales
19.
Am J Psychiatry ; 156(3): 470-3, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10080567

ABSTRACT

OBJECTIVE: This study tested the hypothesis that regional cerebral glucose metabolism during neuronal activation is a more sensitive index of neuronal dysfunction and clinical severity in Alzheimer's disease than is glucose metabolism at rest. METHOD: The subjects were 15 Alzheimer's disease patients with a wide range of Mattis Dementia Rating Scale scores (23-128). By using positron emission tomography, absolute glucose metabolism was measured in the parietal, occipital (visual areas), and temporal (auditory areas) cortical regions during rest (eyes/ears covered) and audiovisual stimulation. RESULTS: In the parietal cortex, glucose metabolism correlated with dementia severity in both conditions. In contrast, in the relatively preserved visual and auditory cortical regions, glucose metabolism predicted dementia severity during stimulation but not at rest. CONCLUSIONS: These findings suggest that regional cerebral glucose metabolism during stimulation is a more sensitive index of the functional/metabolic failure of neuronal systems than is metabolism at rest.


Subject(s)
Alzheimer Disease/diagnosis , Brain/metabolism , Glucose/metabolism , Tomography, Emission-Computed/methods , Acoustic Stimulation , Aged , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/physiopathology , Auditory Cortex/metabolism , Brain/diagnostic imaging , Brain/physiopathology , Female , Fluorodeoxyglucose F18 , Humans , Male , Parietal Lobe/metabolism , Photic Stimulation , Psychiatric Status Rating Scales/statistics & numerical data , Severity of Illness Index , Visual Cortex/metabolism
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