RESUMEN
BACKGROUND AND PURPOSE: Whereas traditional views of language processing in the brain have assumed that the language function is concentrated to a limited number of cortical areas (Broca's and Wernicke's areas), current knowledge points at a much more complex system of language and speech processing involving many brain areas, both cortical and subcortical. The purpose of the current study was to make an unbiased assessment of which cerebral areas are affected in first-ever acute ischaemic stroke patients identified as having language and speech impairments according to the National Institutes of Health Stroke Scale (NIHSS). METHODS: Data from 34 patients with language and speech impairment, with a score of 1-3 on item 9 of the NIHSS, following ischaemic stroke were collected from the Lund Stroke Register. Magnetic resonance images acquired up to 20 days after stroke onset were used to create an overlap lesion image using MRIcron software. RESULTS: The classical language areas, Wernicke's and Broca's areas, were affected in less than one-fourth of the patients. The most frequently affected region was a subcortical region--the left caudate nucleus and the adjacent corona radiata. CONCLUSIONS: These findings contribute to the growing body of evidence that the basal ganglia have a crucial role in the control over language and speech processing.
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Isquemia Encefálica , Núcleo Caudado/patología , Trastornos del Lenguaje , Accidente Cerebrovascular , Adulto , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Isquemia Encefálica/fisiopatología , Femenino , Humanos , Trastornos del Lenguaje/etiología , Trastornos del Lenguaje/patología , Trastornos del Lenguaje/fisiopatología , Masculino , Persona de Mediana Edad , Trastornos del Habla/etiología , Trastornos del Habla/patología , Trastornos del Habla/fisiopatología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/fisiopatología , Adulto JovenRESUMEN
The present study investigated hierarchical lexical semantic structure in oral descriptions of concrete word meanings produced by a subject (ZZ) diagnosed with anomic aphasia due to left occipital lesions. The focus of the analysis was production of a) nouns at different levels of semantic specificity (e.g., "robin"-"bird"-"animal") and b) words describing sensory or motor experiences (e.g., "blue," "soft," "fly"). Results show that in contrast to healthy and aphasic controls, who produced words at all levels of specificity and mainly vision-related sensory information, ZZ produced almost exclusively nouns at the most non-specific levels and words associated with sound and movement.
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Anomia/diagnóstico , Lóbulo Occipital/patología , Semántica , Anciano , Anomia/etiología , Humanos , Masculino , Accidente Cerebrovascular/complicacionesRESUMEN
We describe the synthesis and characterization of the homologous p-iodophenylsilsesquioxanes (SQs) [p-I-C(6)H(4)SiO(1.5)](n) (n = 8, 10, 12) via ICl-promoted iodination (-40 to -60 degrees C) with overall yields of 80-90% and > 95% para selectivity following recrystallization. Characterization by NMR, FTIR, TGA, and single-crystal X-ray diffraction are reported and compared to data previously published for I(8)OPS. Coincidentally, we report a new synthesis of the elusive pentagonal decaphenyl SQ (dPS) [C(6)H(4)SiO(1.5)](10) and its characterization by NMR and single-crystal X-ray studies. These unique macromolecules possess equivalent chemical functionality but varying symmetries (cubic, pentagonal, and D(2d) dodecahedral), offering the potential to develop homologous series of functionalized star and dendrimer compounds with quite different core geometries and thereby providing the potential to greatly vary structure-property relationships in derivative compounds and nanocomposites made therefrom. We find that all three compounds decompose on heating to approximately 400 degrees C/N(2) with loss of I(2) to form robust, microporous materials with BET surface areas of 500-700 m(2)/g, pore volumes of 0.25-0.31 cm(3)/g, average pore widths of 8 A, and oxidative stabilities > or = 500 degrees C and with solid-phase morphologies varying from crystalline to mostly amorphous, as indicated by powder XRD and SEM studies. These latter findings point to important symmetry effects relating directly to packing in the crystalline phase prior to thermolysis.
RESUMEN
A set of stilbene-substituted octasilicates [p-RStil(x)Ph(8-x)SiO(1.5)](8) (R = H, Me, MeO, Cl, NMe(2) and x = 5.3-8) and [o-MeStilSiO(1.5)](8) were prepared. Model compounds were also prepared including the corner and half cages: [p-MeStilSi(OEt)(3)], [p-Me(2)NStilSi(OSiMe(3))(3)], and [p-Me(2)NStilSi(O)(OSiMe)](4). These compounds were characterized by MALDI-TOF, TGA, FTIR, and (1)H NMR techniques. Their photophysical properties were characterized by UV-vis, two-photon absorption, and cathodoluminescence spectroscopy (on solid powders), including studies on the effects of solvent polarity and changes in concentration. These molecules are typically soluble, easily purified, and robust, showing T(d(5%)) > 400 degrees C in air. The full and partial cages all show UV-vis absorption spectra (in THF) identical to the spectrum of trans-stilbene, except for [o-MeStilSiO(1.5)](8), which exhibits an absorption spectrum blue-shifted from trans-stilbene. However, the partial cages show emissions that are red-shifted by approximately 20 nm, as found for stilbene-siloxane macrocycles, suggesting some interaction of the silicon center(s) with the stilbene pi* orbital in both the corner and half cages. In contrast, the emission spectra of the full cages show red-shifts of 60-100 nm. These large red-shifts are supported by density functional theoretical calculations and proposed to result from interactions of the stilbene pi* orbitals with a LUMO centered within the cage that has 4A(1) symmetry and involves contributions from all Si and oxygen atoms and the organic substituents. Given that this LUMO has 3-D symmetry, it appears that all of the stilbene units interact in the excited state, consistent with theoretical results, which show an increased red-shift with an increase in the functionalization of a single corner to functionalization of all eight corners with stilbene. In the case of the Me(2)N- derivatives, this interaction is primarily a charge-transfer interaction, as witnessed by the influence of solvent polarity on the emission behavior. More importantly, the two-photon absorption behavior is 2-3 times greater on a per p-Me(2)Nstilbene basis for the full cage than for the corner or half cages. Similar observations were made for p-NH(2)stilbenevinyl(8)OS cages, where the greater conjugation lengths led to even greater red-shifts (120 nm) and two-photon absorption cross sections. Cathodoluminescence studies done on [p-MeStilSiO(1.5)](8) or [p-MeStilOS](8) powders exhibit essentially the same emissions as seen in solution at high dilution. Given that only the emissions are greatly red-shifted in these molecules, whereas the ground-state UV-vis absorptions are not changed from trans-stilbene, except for the ortho derivative, which is blue-shifted 10 nm. It appears that the interactions are only in the excited state. Theoretical results show that the HOMO and LUMO states are always the pi and pi* states on the stilbene, which show very weak shifts with increasing degrees of functionalization, consistent with the small changes in the UV-vis spectra. The band gap between the lowest unoccupied 4a1 symmetry core state localized inside the silsesquioxane cage and the highest occupied state (pi state on stilbene), however, is markedly decreased as the number of stilbene functional groups is increased. This is consistent with the significant red-shifts in the emission spectra. The results suggest that the emission occurs from the 4a1 state localized on the cage. Moreover, for the compounds [p-RStil(6-7)Ph(2-1)OS](8), the emissions are blue-shifted compared to those of the fully substituted compounds, suggesting the molecular symmetry is reduced (from cubic), thereby reducing the potential for 3-D delocalization and raising the energy of the LUMO. The implications are that these octafunctional molecules exhibit some form of 3-D interaction in the excited state that might permit their use as molecular transistors as well as for energy collection and dispersion as molecular antennas, for example, and for nonlinear optical applications.
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The study objective is to evaluate the results of our surgical technique for children with congenital adrenal hyperplasia and ambiguous genitalia at the University Hospital of Heidelberg, Department of Paediatric Surgery. The records of 19 patients with congenital adrenal hyperplasia treated between 1972 and 2004 were reviewed with respect to age at surgery, operative procedures and outcome. We describe the recession clitoroplasty technique currently used in our hospital and highlight the importance of short and long-term follow-up results with respect to appearance, position and size of the clitoris and quality of the vagina. One-stage recession clitoroplasty and vaginoplasty gives very satisfactory cosmetic and functional results, with few complications and a reduced need for secondary surgical interventions. The results of this study support the assumption that total correction can be achieved through a single-stage operation, performed in infancy.
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Hiperplasia Suprarrenal Congénita/cirugía , Clítoris/cirugía , Procedimientos Quirúrgicos Ginecológicos/métodos , Vagina/cirugía , Preescolar , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Humanos , Reoperación , Estudios RetrospectivosRESUMEN
PURPOSE: Conformal stereotactic radiosurgery and radiotherapy using a linear accelerator and a micromultileaf collimator (mMLC) offer the possibility of irradiating irregularly shaped target volumes. Dynamic arc radiosurgery and radiotherapy, i.e., stereotactic radiation therapy combining a moving gantry with a dynamic mMLC, enable the radiation even of lesions with concave structures. METHODS AND MATERIALS: The dynamic arc method requires additional tools for quality assurance (QA) and three-dimensional verification at a high spatial resolution. A QA program was developed. Dose distributions of planning target volumes with concavities were investigated in polymer gel phantoms. The radiation-induced change of the relaxation rate R(2) was measured by magnetic resonance imaging. The distributions were compared with image processing tools. RESULTS: Using the therapy-planning software BrainSCAN 4.0 (and 4.1 beta) in combination with the mMLC m3, deviations between the planned and measured 90% isodoses of about 2 mm were registered in the isocenter plane. Three-dimensional verification was feasible in the range of accuracy achieved in planning and dose measurement. CONCLUSIONS: Dynamic arc radiosurgery and radiotherapy offer excellent conformation even for complicated planning target volumes with concavities. The dose distribution calculated with the treatment-planning software used can be accomplished with the available equipment. Patients can be treated by dynamic arc radiosurgery and radiotherapy.
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Fantasmas de Imagen , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/métodos , Calibración , Terapia Combinada , Humanos , Imagen por Resonancia Magnética , Aceleradores de Partículas , Fenómenos Físicos , Física , Control de Calidad , Radiocirugia/instrumentación , Radiocirugia/normas , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/instrumentación , Planificación de la Radioterapia Asistida por Computador/normas , Radioterapia Conformacional/instrumentación , Radioterapia Conformacional/normasRESUMEN
An outbreak of hepatitis B virus (HBV) infection in a haemodialysis unit is described. Four patients in the unit contracted subclinical HBV infection within three months. DNA sequence analysis of the S gene of HBV isolates from chronic carriers and newly infected patients in the unit aided in tracing possible transmission pathways. Three newly infected patients had received partial or complete HBV vaccination previously. HBV was rapidly cleared from all three although the anti-HBs titre had not reached 10 IU L-1 in any of them at the time of infection.
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Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Análisis de Secuencia de ADN , Infección Hospitalaria/prevención & control , Infección Hospitalaria/virología , ADN Viral , Unidades de Hemodiálisis en Hospital , Hepatitis B/prevención & control , Hepatitis B/virología , Vacunas contra Hepatitis B , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Suecia/epidemiología , VacunaciónRESUMEN
Personality and life events were measured in 69 consecutive patients (36 men and 33 women) below age 40 attending the emergency care unit because of chest pain without obvious organic cause (91% participation rate). The results were compared with 32 randomly sampled healthy subjects matched with regard to age and sex (86% participation rate). The patient group had significantly higher scores for "neuroticism', 'Type A behaviour' and 'vital exhaustion'. Further more the patients had experienced significantly more life events, in particular uncontrollable ones, during the last year. We conclude that 'Type A behaviour', 'neuroticism', 'vital exhaustion' and critical recent life events are linked with emergency consultation for chest pain of non-cardiac origin. Possible explanations of the link between the psychological reaction and the chest pain are enhanced tension in the thoracic muscles producing chest pain and oesophageal disorders. This study stresses the importance of careful medical and psychosocial examination of each case of unexplained chest pain at the emergency care unit.
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Dolor en el Pecho/psicología , Acontecimientos que Cambian la Vida , Personalidad , Trastornos Somatomorfos/psicología , Enfermedad Aguda , Adulto , Dolor en el Pecho/complicaciones , Servicio de Urgencia en Hospital , Femenino , Humanos , Masculino , Trastornos Neuróticos/complicaciones , Inventario de Personalidad , Trastornos Somatomorfos/complicaciones , Personalidad Tipo ARESUMEN
Elevated levels of aluminum in brain tissue have been found in demented patients with Alzheimer's disease, with ALS-PD complex of Guam and with dialysis encephalopathy. A possible etiological relationship between enhanced aluminum exposure and impaired mental function was suggested both for ALS-PD of Guam (a region where high contents of aluminum in water are found) and for dialysis encephalopathy which appears in dialyzed patients exposed to high doses of aluminum in medications and in dialysate fluid. The role of aluminum in Alzheimer's disease is not known as is the question of life-long aluminum accumulation in healthy human beings. In this review we have limited ourselves to the issue of oral aluminum ingestion and the possible neurotoxic consequences of such exposure. The following topics are summarized: 1. Physiological mechanisms involved in ingestion and intestinal absorption of aluminum and the influences of pH and available organic complexing agents on these processes. 2. Effects of an aluminum-enriched diet on behavior and on brain metabolism. 3. Dietary sources of aluminum and elevated loads of this substance due to prolonged intake of aluminum-containing medications. The main conclusion of this summary is that aluminum is absorbed and may accumulate in different organs in both adults and infants. Two groups seem to be at particular risk for aluminum related toxicity: people with chronic renal failure treated with aluminum-containing medications and pre-term infants fed on aluminum containing formulate. It seems probable that at least upon short term exposure the healthy human body can defend itself adequately from aluminum's toxic effects. However, not enough information is available on possible effects of life-long exposure to aluminum in the environment, diet and medications, which over decades may lead to accumulation of this substance with expressions of toxicity. Therefore, the question of aluminum's relevance to dementive diseases cannot yet be adequately answered.
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Aluminio/efectos adversos , Aluminio/farmacocinética , Enfermedad de Alzheimer/inducido químicamente , Absorción Intestinal , Aluminio/análisis , Aluminio/química , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Gatos , Utensilios de Comida y Culinaria , Dieta/efectos adversos , Humanos , Lactante , Alimentos Infantiles/análisis , Ratones , Preparaciones Farmacéuticas/química , Ratas , Té/químicaRESUMEN
BACKGROUND AND PURPOSE: Recently introduced 320-detector row CT enables whole brain perfusion imaging compared to a limited scanning area in 64-detector row CT. Our aim was to evaluate patient radiation exposure in comprehensive stroke imaging by using multidetector row CT consisting of standard CT of the head, CTA of cerebral and cervical vessels, and CTP. MATERIAL AND METHODS: Organ doses were measured by using LiF-TLDs located at several organ sites in an Alderson-Rando phantom. Effective doses were derived from these measurements. Stroke protocols including noncontrast head CT, CTA of cerebral and cervical vessels, and CTP were performed on 320- and 64-detector row scanners. RESULTS: Measured effective doses for the different scanning protocols ranged between 1.61 and 4.56 mSv, resulting in an effective dose for complete stroke imaging of 7.52/7.54 mSv (m/f) for 64-detector row CT and 10.56/10.6 mSv (m/f) for 320-detector row CT. The highest organ doses within the area of the primary beam were measured in the skin (92 mGy) and cerebral hemispheres (69.91 mGy). Use of an eye-protection device resulted in a 54% decrease of the lens dose measured for the combo protocol for whole-brain perfusion with the 320-detector row CT scanner. CONCLUSIONS: Phantom measurements indicate that comprehensive stroke imaging with multidetector row CT may result in effective radiation doses from 7.52 mSv (64-detector row CT) to 10.6 mSv (320-detector row CT). The technique of 320-detector row CT offers additional information on the time course of vascular enhancement and whole-brain perfusion. Physicians should weigh the potential of the new technique against the higher radiation dose that is needed. Critical doses that would cause organ damage were not reached.
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Encéfalo/diagnóstico por imagen , Fantasmas de Imagen , Radiometría/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/métodos , Seguridad de Equipos , Femenino , Humanos , Cristalino/diagnóstico por imagen , Masculino , Modelos Anatómicos , Dosis de Radiación , Reproducibilidad de los Resultados , Base del Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X/normasAsunto(s)
Paro Cardíaco/terapia , Marcapaso Artificial , Anciano , Urgencias Médicas , Femenino , HumanosRESUMEN
A hyperventilation provocation test (HVPT) was performed on a group (n = 63) of consecutive patients, below the age of 40 years, attending an emergency care unit complaining of chest pain without obvious organic cause. The results were compared with those for a control group (n = 32). There was no tendency to hyperventilate in the patient group, either after discontinuing hyperventilation or during the ensuing relaxation period. PETCO2 measurements during this time thus showed no significant differences between the patient group and the control group. During the HVPT, 44% of patients reported three or more listed symptoms familiar to them from earlier occasions and regarded as typical of hyperventilation, compared to 23% of the controls (P less than 0.05). In a previously reported study, 38% of the patients were found to have similar symptoms during standardized mental stress, despite lack of hypocapnia. It is concluded that, on the basis of PETCO2 measurements, there were no signs of abnormal hyperventilation in the patient group. Moreover, the HVPT did not appear to be specific for diagnosis of hyperventilation syndrome, since mental stress itself was able to reproduce symptoms without concomitant hypocapnia, and since the provocation test was 'positive' in many control subjects.
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Dolor en el Pecho/etiología , Hiperventilación/fisiopatología , Estrés Psicológico/fisiopatología , Adulto , Presión Sanguínea/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , MasculinoRESUMEN
Reactivity to mental stress and relaxation was studied in 63 consecutive patients below the age of 40 attending the emergency care unit because of chest pain without obvious organic cause. The results were compared with a control group (n = 32). Of the patients, 41% reported chest pain or oppression in the chest during mental stress compared to 10% of the control subjects (p less than 0.01). During relaxation the subjects in the female patient group reported significantly less ability to relax and had significantly higher respiration rate as compared to the female control group. There were no significant differences between the groups regarding heart rate, blood pressure or end-tidal PCO2 and there was no evidence of hyperventilation, neither during relaxation nor during mental stress. In combination with our earlier findings of high scores for "type A behaviour", "neuroticism", "vital exhaustion" and "stressful life events" these findings indicate that psychosomatic mechanisms may be of great importance for the development of chest pain in this group of patients.
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Dolor en el Pecho/etiología , Respiración , Estrés Psicológico/complicaciones , Enfermedad Aguda , Adolescente , Adulto , Dolor en el Pecho/fisiopatología , Femenino , Hemodinámica , Humanos , Masculino , RelajaciónRESUMEN
The influence of aluminium (20-50 micrograms/ml) on neuronal function was examined using electrophysiological techniques and neuroblastoma clone cells which offer a convenient model of differentiating and fully active neurons. Two specific questions were addressed: 1) Can differentiated cells maintain their normal excitable function when exposed to aluminium? 2) Can proper development of electrophysiological properties be achieved in its presence? We report that aluminium caused premature onset of deterioration in fully differentiated cells. Within 4-6 days they depolarized from -29.3 +/- 0.9 mV to levels lower than -15 mV; compound polyphasic action potentials were gradually replaced by slow monophasic spikes before the final loss of excitable properties and structural deformations was noticed. Developing cells followed the normal pattern of differentiation in the presence of aluminium: within 7 days they extended neurites, hyperpolarized and exhibited polyphasic spikes. These results show that neuroblastoma cells are apparently less susceptible to aluminium's toxicity during the process of development than after differentiation. Possible mechanisms by which aluminium may exert its effects are discussed in view of these observations.
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Aluminio/toxicidad , Proteínas del Tejido Nervioso/metabolismo , Neuroblastoma/patología , Animales , Diferenciación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Electrofisiología , Ratones , Neuroblastoma/metabolismo , Factores de Tiempo , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/patologíaRESUMEN
A five-year follow-up, by means of a personal interview, was performed on patients below the age of 40 years with acute chest pain without obvious organic cause (n = 64). They had been consecutively admitted to the emergency unit over a period of 8 weeks, and had all been subjected to a thorough medical and psychosocial investigation with feedback soon after the initial consultation (investigation patient group, IP). For comparison, a non-investigation patient (NIP) group (n = 51) was recruited over a period of 8 separate weeks. Half of the patients in each group reported at the follow-up that they continued to suffer from chest pain. Compared to normal subjects, they reported more depression. This means that the initial research programme performed in the investigation group had no sustained therapeutic effect compared to routine care at the emergency unit. Tension, anxiety and number of consultations with a physician, as reported in the initial investigation, were negatively correlated with the outcome at follow-up. We conclude that acute chest pain without obvious organic cause in young adults is a condition with an excellent prognosis in strictly physical terms. However, a high proportion of the patients continue to suffer from chest pain for several years, and many of them continue to be consumers of medical resources. We therefore suggest that therapeutic programmes should be developed, particularly for those who report psychological symptoms and those with a history of many consultations with physicians.