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1.
Opt Lett ; 30(13): 1641-3, 2005 Jul 01.
Article in English | MEDLINE | ID: mdl-16075523

ABSTRACT

We present a method of analysis of images of dynamic speckle based on the filtering in frequency bands of the temporary history of each pixel. Butterworth filters are applied to the temporary evolution, and different images are constructed showing the energy in each frequency band. Different degrees of activity of the sample in study, presumably attributed to different origins, are found. The method is exemplified with images of bruising damage in fruits and of biological activity in germinating corn seeds. It is found that the activity in the bruised region of an apple differs from the activity of healthy regions in a certain characteristic frequency range. The activity of the embryo can also be distinguished from that of the endosperm in corn seeds during germination.


Subject(s)
Algorithms , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Lasers , Fruit/anatomy & histology , Information Storage and Retrieval/methods , Malus/anatomy & histology , Seeds/anatomy & histology , Zea mays/anatomy & histology
2.
Rev Neurol ; 40(8): 465-72, 2005.
Article in Spanish | MEDLINE | ID: mdl-15861327

ABSTRACT

INTRODUCTION: The cerebellum has been traditionally associated with motor control learning and performance. However, since 1970 a growing body of clinical and experimental evidences has suggested that the cerebellum may be involved in nonmotor cognitive functions as well. OBJECTIVE: To explore the presence of eventual cognitive impairment in non-demented patients with isolated degenerative cerebellar diseases. PATIENTS AND METHODS: Twelve patients with the diagnosis of selective degenerative cerebellar disorders, either inherited or sporadic, were selected (mean age: 40.42 +/- 13.49 years; mean education level: 9.92 +/- 3.99 years; duration of illness: 12.13 +/- 11.27 years, MMSE: 26.75 +/- 1.5) and evaluated through a standardized neuropsychological tests battery. Normalized Z scores were estimated and compared against 0, employing the t test for one sample. RESULTS: Significant cognitive deficits were found in the following domains: executive, visuo-spatial, memory and attention functions. Performance on the Wisconsin test showed a significative number of perseverative errors. Memory deficits included verbal learning and free recall difficulties, with good recognition of the material presented. CONCLUSIONS: The findings of this study are consistent with the role of the cerebellum as modulator of mental functions. The cognitive deficits resulting from cerebellar pathology may be related with the disruption of cerebello-cortical connexions involving a complex network which includes the prefrontal region, suggesting that the cerebellum may process cortical information coming from different areas linked with the control of cognition.


Subject(s)
Cerebellar Diseases/physiopathology , Cerebellum/pathology , Neuropsychological Tests , Adolescent , Adult , Cerebellum/physiology , Cognition/physiology , Cognition Disorders/physiopathology , Female , Humans , Male , Memory Disorders/physiopathology , Middle Aged
3.
Rev. neurol. (Ed. impr.) ; 40(8): 465-472, 16 abr., 2005. ilus, tab, graf
Article in Es | IBECS | ID: ibc-037066

ABSTRACT

Introducción. El cerebelo se ha asociado tradicionalmente con el aprendizaje y el control motor. Sin embargo, en las últimas tres décadas se ha obtenido evidencia clínica y experimental que sugiere que el cerebelo podría intervenir en el procesamiento cognitivo no motor. Objetivo. Estudiar el rendimiento neuropsicológico de pacientes con enfermedad cerebelosa degenerativa pura no dementes. Pacientes y métodos. Se evaluaron 12 pacientes con enfermedad cerebelosa degenerativa pura, de causa hereditaria o de presentación esporádica (edad: 40,42 13,49 años; educación: 9,92 3,99 años; tiempo de evolución: 12,13 11,27 años; MMSE: 26,75 1,5) por medio de una batería neuropsicológica estandarizada. Se calcularon puntuaciones normalizadas Z, que se compararon contra 0 mediante el empleo de pruebas de t de una muestra. Resultados. Se observaron alteraciones significativas en las pruebas de función ejecutiva, visuoespacial, memoria y atención. En el test de Wisconsin se registró un número significativo de errores perseverativos. Los fallos en memoria se caracterizaron por dificultades en el aprendizaje y la evocación diferida, con buen desempeño en el reconocimiento del material presentado. Los déficit cognitivos no se correlacionaron con la gravedad del déficit motor elemental. Conclusiones. Los datos obtenidos sugieren la participación del cerebelo en la modulación de las funciones mentales


Introduction. The cerebellum has been traditionally associated with motor control learning and performance. However, since 1970 a growing body of clinical and experimental evidences has suggested that the cerebellum may be involved in nonmotor cognitive functions as well. Objective. To explore the presence of eventual cognitive impairment in non-demented patients with isolated degenerative cerebellar diseases. Patients and methods. Twelve patients with the diagnosis of selective degenerative cerebellar disorders, either inherited or sporadic, were selected (mean age: 40.42 ± 13.49 years; mean education level: 9.92 ± 3.99 years; duration of illness: 12.13 ± 11.27 years, MMSE: 26.75 ± 1.5) and evaluated through a standardized neuropsychological tests battery. Normalized Z scores were estimated and compared against 0, employing the t test for one sample. Results. Significant cognitive deficits were found in the following domains: executive, visuo-spatial, memory and attention functions. Performance on the Wisconsin test showed a significative number of perseverative errors. Memory deficits included verbal learning and free recall difficulties, with good recognition of the material presented. Conclusions. The findings of this study are consistent with the role of the cerebellum as modulator of mental functions. The cognitive deficits resulting from cerebellar pathology may be related with the disruption of cerebello-cortical connexions involving a complex network which includes the prefrontal region, suggesting that the cerebellum may process cortical information coming from different areas linked with the control of cognition


Subject(s)
Male , Female , Adult , Adolescent , Middle Aged , Humans , Cerebellar Diseases/physiopathology , Neurodegenerative Diseases/physiopathology , Ataxia/diagnosis , Neurobehavioral Manifestations , Cognition Disorders/diagnosis , Memory Disorders/diagnosis , Severity of Illness Index , Neuropsychological Tests/statistics & numerical data
4.
Eur Biophys J ; 33(8): 694-9, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15133648

ABSTRACT

The work reported here describes the application of the optical technique known as dynamic speckle interferometry to evaluate the motility of nematode parasites exposed to different anthelmintic drugs. This technique, a well proven tool for assessing the time evolution of different phenomena, is here successfully used to quantify parasite motility in pharmacodynamic assays. The characterization of the pharmacological properties of anthelmintic drugs is critical to optimize their use in parasite control. Besides, the evaluation of nematode motility is a relevant indicator of the pharmacodynamic effect of anthelmintic drugs. The application of this approach to study the motility of Haemonchus contortus (used as a model of nematode parasites) larvae exposed to different drugs is presented, showing its usefulness.


Subject(s)
Anthelmintics/pharmacology , Anthelmintics/pharmacokinetics , Haemonchus/physiology , Image Interpretation, Computer-Assisted/methods , Interferometry/methods , Movement/physiology , Animals , Haemonchus/drug effects , Movement/drug effects , Pharmacokinetics , Pharmacology/methods
5.
J Clin Exp Neuropsychol ; 22(5): 677-85, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11094402

ABSTRACT

We have sought to adapt and validate a NART-like Spanish test, the Word Accentuation Test (WAT: Del Ser, Montalvo, Espinosa, Villapalos, & Bermejo, 1997) to estimate acquired intelligence in local normal older adults. The test requires examinees to read aloud infrequent, irregularly stressed Spanish words, a situation that presumably requires lexical knowledge. Results in a sample of 74 participants show that the revised WAT (i.e., the WAT for Buenos Aires) has good concurrent validity with the WAIS Vocabulary subtest and number of years of formal education, as well as high internal consistency. Performance on this test was dissociated from age, memory, or frontal/executive measures.


Subject(s)
Intelligence , Language Tests/standards , Phonetics , Reading , Aged , Aged, 80 and over , Argentina , Factor Analysis, Statistical , Female , Humans , Male , Neuropsychological Tests/standards , Psychometrics , Wechsler Scales/standards
6.
Alzheimer Dis Assoc Disord ; 13 Suppl 3: S201-5, 1999.
Article in English | MEDLINE | ID: mdl-10609701

ABSTRACT

Population aging is a process that is especially accelerated in some parts of the world. One example is in Latin America. As with other developing regions, Latin America has to confront population "graying" in the context of an emerging economy. As a result of this and of their health history, the prevalence and incidence of age-related pathologies are different than those in the developed world. The burden of dementia is significant for patients, families, health systems, and public health. The aim of this paper was to summarize data from the scarce dementia epidemiological studies available in Latin America, the diagnostic criteria used in most countries and the most widely used diagnostic tools and neuropsychological assessment instruments (some of them translated, validated, and harmonized). Reference is made to the approval process and availability in Argentina of dementia and cognitive decline-related drugs.


Subject(s)
Dementia, Vascular/diagnosis , Dementia, Vascular/epidemiology , Developing Countries/statistics & numerical data , Dementia/drug therapy , Dementia, Vascular/psychology , Humans , Latin America , Neuropsychological Tests , Prevalence
8.
Neuroepidemiology ; 18(5): 231-5, 1999.
Article in English | MEDLINE | ID: mdl-10461047

ABSTRACT

Latin-American countries are expected to experience an expansion of the elderly population, as life expectancy increases. We reviewed the literature to determine the frequency of dementia in our region and surveyed selected Latin-American countries to determine the availability of diagnostic and treatment services and long-term care facilities. Latin-American countries face a challenge to develop public health strategies to cope with the anticipated heightened number of elderly with cognitive impairment.


Subject(s)
Dementia/epidemiology , Developing Countries , Adult , Aged , Argentina/epidemiology , Cross-Sectional Studies , Dementia/etiology , Female , Humans , Incidence , Latin America/epidemiology , Male , Middle Aged , Population Growth
11.
Appl Opt ; 36(26): 6636-45, 1997 Sep 10.
Article in English | MEDLINE | ID: mdl-18259526

ABSTRACT

Some properties of optical correlation based on the fractional Fourier transform are analyzed. For a particular set of fractional orders, a filter is obtained that becomes insensitive to scale variations of the object. An optical configuration is also proposed to carry out the fractional correlation in a flexible way, and some experimental results are shown.

12.
Buenos Aires; Ediciones Sagitario; 1997. 495 p.
Monography in Spanish | LILACS | ID: lil-598830
13.
Appl Opt ; 33(20): 4358-60, 1994 Jul 10.
Article in English | MEDLINE | ID: mdl-20935794

ABSTRACT

We present a digital speckle-pattern interferometric setup that can be operated at TV frame rates (30 ms) to display the locus of the points at which the optical-path difference between the reference and object beams is within the coherence length. Experimental results are shown.

14.
Appl Opt ; 33(20): 4369-72, 1994 Jul 10.
Article in English | MEDLINE | ID: mdl-20935796

ABSTRACT

Digital speckle pattern interferometry provides information on deformations equivalent to that given by image holography. Thus more than one viewpoint is necessary for the description of three-dimensional deformation vectors. We report the use of a diffraction-grating technique to process simultaneously the three or more required viewpoints of a digital holography experiment.

15.
Appl Opt ; 22(6): 881, 1983 Mar 15.
Article in English | MEDLINE | ID: mdl-18195892
16.
Am J Pediatr Hematol Oncol ; 5(1): 79-86, 1983.
Article in English | MEDLINE | ID: mdl-6574715

ABSTRACT

Neurological, psychopedagogic, and psychologic long-term sequelae were evaluated in two groups of ALL patients in continuous CR for more than 2 years treated with two different CNS prophylaxis schemes. Group A, 19 patients (protocol 10-LLA-72 GATLA) received cranial irradiation 2400 rads plus IT MTX-DMT, and group B, 23 patients (protocol 1-LLA-76-GATLA) IT MTX-DMT only during induction and maintenance. All the patients were evaluated by performing neurological examination, EEG, EMG with nerve conduction velocity, CT scans, CSF studies, psychometric and psychologic studies, and neuropsychological evaluation. The most important findings were: 11 patients from group A (58%) showed abnormal CT (low density areas in the periventricular white matter, widening of subarachnoid space, ventricular dilatation, intracerebral calcification) and only one patient from group B showed CT abnormalities (p less than 0.0005). The neuropsychologic evaluation (performed by L. Bender technique and Picq-Vayer scale) showed more severe impairment (grade 3-4) in eight patients from group A (42%) and none in group B (p less than 0.001). Higher incidence of abnormalities in group A suggests the existence of more severe sequelae in the patients treated with cranial irradiation plus IT MTX-DMT than with IT MTX-DMT alone.


Subject(s)
Dexamethasone/therapeutic use , Leukemia, Lymphoid/psychology , Meningeal Neoplasms/prevention & control , Methotrexate/therapeutic use , Nervous System Neoplasms/prevention & control , Skull/radiation effects , Adolescent , Adult , Brain/diagnostic imaging , Brain/drug effects , Brain Diseases/etiology , Child , Child, Preschool , Female , Humans , Infant , Intelligence Tests , Male , Psychomotor Performance , Tomography, X-Ray Computed
17.
Appl Opt ; 21(12): 2099-100, 1982 Jun 15.
Article in English | MEDLINE | ID: mdl-20395989
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