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1.
Neurosci Res ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582242

RESUMO

The Stroop Task is a well-known neuropsychological task developed to investigate conflict processing in the human brain. Our group has utilized direct intracranial neural recordings in various brain regions during performance of a modified color-word Stroop Task to gain a mechanistic understanding of non-emotional human conflict processing. The purpose of this review article is to: 1) synthesize our own studies into a model of human conflict processing, 2) review the current literature on the Stroop Task and other conflict tasks to put our research in context, and 3) describe how these studies define a network in conflict processing. The figures presented are reprinted from our prior publications and key publications referenced in the manuscript. We summarize all studies to date that employ invasive intracranial recordings in humans during performance of conflict-inducing tasks. For our own studies, we analyzed local field potentials (LFPs) from patients with implanted stereotactic electroencephalography (SEEG) electrodes, and we observed intracortical oscillation patterns as well as intercortical temporal relationships in the hippocampus, amygdala, and orbitofrontal cortex (OFC) during the cue-processing phase of a modified Stroop Task. Our findings suggest that non-emotional human conflict processing involves modulation across multiple frequency bands within and between brain structures.

2.
Turk Neurosurg ; 34(1): 128-134, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38282591

RESUMO

AIM: To investigate the relationship between planned drill approach angle and angular deviation of the stereotactically placed intracranial electrode tips. MATERIAL AND METHODS: Stereotactic electrode implantation was performed in 13 patients with drug resistant epilepsy. A total of 136 electrodes were included in our analysis. Stereotactic targets were planned on pre-operative magnetic resonance imaging (MRI) scans and implantation was carried out using a Cosman-Roberts-Wells stereotactic frame with the Ad-Tech drill guide and electrodes. Post implant electrode angles in the axial, coronal, and sagittal planes were determined from post-operative computerized tomography (CT) scans and compared with planned angles using Bland-Altman plots and linear regression. RESULTS: Qualitative assessment of correlation plots between planned and actual angles demonstrated a linear relationship for axial, coronal, and sagittal planes, with no overt angular deflection for any magnitude of the planned angle. CONCLUSION: The accuracy of CRW frame-based electrode placement using the Ad-Tech drill guide and electrodes is not significantly affected by the magnitude of the planning angle. Based on our results, oblique electrode insertion is a safe and accurate procedure.


Assuntos
Epilepsia Resistente a Medicamentos , Técnicas Estereotáxicas , Humanos , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Imageamento Tridimensional , Eletrodos Implantados , Imageamento por Ressonância Magnética
3.
Clin Neurophysiol ; 152: 93-111, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37208270

RESUMO

Neurostimulation has diverse clinical applications and potential as a treatment for medically refractory movement disorders, epilepsy, and other neurological disorders. However, the parameters used to program electrodes-polarity, pulse width, amplitude, and frequency-and how they are adjusted have remained largely untouched since the 1970 s. This review summarizes the state-of-the-art in Deep Brain Stimulation (DBS) and highlights the need for further research to uncover the physiological mechanisms of neurostimulation. We focus on studies that reveal the potential for clinicians to use waveform parameters to selectively stimulate neural tissue for therapeutic benefit, while avoiding activating tissue associated with adverse effects. DBS uses cathodic monophasic rectangular pulses with passive recharging in clinical practice to treat neurological conditions such as Parkinson's Disease. However, research has shown that stimulation efficiency can be improved, and side effects reduced, through modulating parameters and adding novel waveform properties. These developments can prolong implantable pulse generator lifespan, reducing costs and surgery-associated risks. Waveform parameters can stimulate neurons based on axon orientation and intrinsic structural properties, providing clinicians with more precise targeting of neural pathways. These findings could expand the spectrum of diseases treatable with neuromodulation and improve patient outcomes.


Assuntos
Estimulação Encefálica Profunda , Doenças do Sistema Nervoso , Doença de Parkinson , Humanos , Estimulação Encefálica Profunda/efeitos adversos , Eletrodos , Neurofisiologia
4.
J Neural Eng ; 19(4)2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35803209

RESUMO

Objective.This study aimed to characterize hippocampal neural signatures of uncertainty by measuring beta band power in the period prior to movement cue.Approach. Participants with epilepsy were implanted with hippocampal depth electrodes for stereo electroencephalographic (SEEG) monitoring. Hippocampal beta (13-30 Hz) power changes have been observed during motor tasks such as the direct reach (DR) and Go/No-Go (GNG) tasks. The primary difference between the tasks is the presence of uncertainty about whether movement should be executed. Previous research on cortical responses to uncertainty has found that baseline beta power changes with uncertainty. SEEG data were sampled throughout phases of the DR and GNG tasks. Beta-band power during the fixation phase was compared between the DR and GNG task using a Wilcoxon rank sum test. This unpaired test was also used to analyze response times from cue to task completion between tasks.Main results.Eight patients who performed both reaching tasks were analyzed in this study. Movement response times in the GNG task were on average 210 milliseconds slower than in the DR task. All patients exhibited a significantly increased response latency in the GNG task compared to the DR task (Wilcoxon rank-sum p-value < 0.001). Six out of eight patients demonstrated statistically significant differences in beta power in single hippocampal contacts between the fixation phases of the GNG and DR tasks. At the group level, baseline beta power was significantly lower in the GNG task than in the DR task (Wilcoxon rank-sum p-value < 0.001).Significance. This novel study found that, in the presence of task uncertainty, baseline beta power in the hippocampus is lower than in its absence. This finding implicates movement uncertainty as an important factor in baseline hippocampal beta power during movement preparation.


Assuntos
Eletroencefalografia , Movimento , Hipocampo , Humanos , Movimento/fisiologia , Tempo de Reação/fisiologia , Incerteza
5.
Neuromodulation ; 25(2): 232-244, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35125142

RESUMO

INTRODUCTION: The hippocampus is thought to be involved in movement, but its precise role in movement execution and inhibition has not been well studied. Previous work with direct neural recordings has found beta-band (13-30 Hz) modulation in both movement execution and inhibition throughout the motor system, but the role of beta-band modulation in the hippocampus during movement inhibition is not well understood. Here, we perform a Go/No-Go reaching task in ten patients with medically refractory epilepsy to study human hippocampal beta-power changes during movement. MATERIALS AND METHODS: Ten epilepsy patients (5 female; ages 21-46) were implanted with intracranial depth electrodes for seizure monitoring and localization. Local field potentials were sampled at 2000 Hz during a Go/No-Go movement task. Comparison of beta-band power between Go and No-Go conditions was conducted using Wilcoxon signed-rank hypothesis testing for each patient. Sub-analyses were conducted to assess differences in the anterior vs posterior contacts, ipsilateral vs contralateral contacts, and male vs female beta-power values. RESULTS: Eight out of ten patients showed significant beta-power decreases during the Go movement response (p < 0.05) compared to baseline. Eight out of ten patients also showed significant beta-power increases in the No-Go condition, occurring in the absence of movement. No significant differences were noted between ipsilateral vs contralateral contacts nor in anterior vs posterior hippocampal contacts. Female participants had a higher task success rate than males and had significantly greater beta-power increases in the No-Go condition (p < 0.001). CONCLUSION: These findings indicate that increases in hippocampal beta power are associated with movement inhibition. To the best of our knowledge, this study is the first to report this phenomenon in the human hippocampus. The beta band may represent a state-change signal involved in motor processing. Future focus on the beta band in understanding human motor and impulse control will be vital.


Assuntos
Eletroencefalografia , Epilepsia , Adulto , Epilepsia/terapia , Feminino , Hipocampo , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Adulto Jovem
6.
J Neural Eng ; 19(1)2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35086075

RESUMO

Objective. The human orbitofrontal cortex (OFC) is involved in automatic response inhibition and conflict processing, but the mechanism of frequency-specific power changes that control these functions is unknown. Theta and gamma activity have been independently observed in the OFC during conflict processing, while theta-gamma interactions in other brain areas have been noted primarily in studies of memory. Within the OFC, it is possible that theta-gamma phase amplitude coupling (PAC) drives conflict processing. This study aims to characterize the coupled relationship between theta and gamma frequency bands in the OFC during conflict processing using a modified Stroop task.Approach. Eight epilepsy patients implanted with OFC stereotactic electroencephalography electrodes participated in a color-word modified Stroop task. PAC between theta phase and gamma amplitude was assessed to determine the timing and magnitude of neural oscillatory changes. Group analysis was conducted using a non-parametric cluster-permutationt-test on coherence values.Main results.Theta-low gamma (LG) PAC significantly increased in five out of eight patients during successful trials of the incongruent condition compared with the congruent condition. Significant increases in theta-LG PAC were most prominent during cue processing 200-800 ms after cue presentation. On group analysis, trial-averaged mean theta-LG PAC was statistically significantly greater in the incongruent condition compared to the congruent condition (p< 0.001, Cohen'sd= 0.51).Significance.For the first time, we report that OFC theta phase and LG amplitude coupling increases during conflict resolution. Given the delayed onset after cue presentation, OFC theta-LG PAC may contribute to conflict processing after conflict detection and before motor response. This explanation follows the hypothesis that global theta waves modulate local gamma signals. Understanding this relationship within the OFC will help further elucidate the neural mechanisms of human conflict resolution.


Assuntos
Conflito Psicológico , Córtex Pré-Frontal , Eletroencefalografia , Epilepsia , Humanos , Córtex Pré-Frontal/fisiologia , Teste de Stroop
7.
Front Physiol ; 12: 724027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925052

RESUMO

In this paper, a new electromyographic phenomenon, referred to as Bursting Rate Variability (BRV), is reported. Not only does it manifest itself visually as a train of short periods of accrued surface electromyographic (sEMG) activity in the traces, but it has a deeper underpinning because the sEMG bursts are synchronous with wavelet packets in the D8 subband of the Daubechies 3 (db3) wavelet decomposition of the raw signal referred to as "D8 doublets"-which are absent during muscle relaxation. Moreover, the db3 wavelet decomposition reconstructs the entire sEMG bursts with two contiguous relatively high detail coefficients at level 8, suggesting a high incidence of two consecutive neuronal discharges. Most importantly, the timing between successive bursts shows some variability, hence the BRV acronym. Contrary to Heart Rate Variability (HRV), where the R-wave is easily identified, here, time-localization of the burst requires a statistical waveform matching between the "D8 doublet" and the burst in the raw sEMG signal. Furthermore, statistical fitting of the empirical distribution of return times shows a striking difference between control and quadriplegic subjects. Finally, the BRV rate appears to be within 60-88 bursts per minute on average among 9 human subjects, suggesting a possible connection between BRV and HRV.

8.
J Clin Neurosci ; 91: 183-192, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34373025

RESUMO

The amygdala is a medial temporal lobe structure known to be involved in processing emotional conflict. However, its role in processing non-emotional conflict is not well understood. Previous studies have utilized the Stroop Task to examine brain modulation of humans under the color-word conflict scenario, which is non-emotional conflict processing, and found hippocampal theta-band (4-7 Hz) modulation. This study aims to survey amygdaloid theta power changes during non-emotional conflict processing using intracranial depth electrodes in nine epileptic patients (3 female; age 20-62). All patients were asked to perform a modified Stroop task. During task performance, local field potential (LFP) data was recorded from macro contacts sampled at 2 K Hz and used for analysis. Mean theta power change from baseline was compared between the incongruent and congruent task condition groups using a paired sample t-test. Seven patients were available for analysis after artifact exclusion. In five out of seven patients, statistically significant increases in theta-band power from baseline were noted during the incongruent task condition (paired sample t-test p < 0.001), including one patient exhibiting theta power increases in both task conditions. Average response time was 1.07 s (failure trials) and 1.04 s (success trials). No speed-accuracy tradeoff was noted in this analysis. These findings indicate that human amygdaloid theta-band modulation may play a role in processing non-emotional conflict. It builds directly upon work suggesting that the amygdala processes emotional conflict and provides a neurophysiological mechanism for non-emotional conflict processing as well.


Assuntos
Conflito Psicológico , Adulto , Eletroencefalografia , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Teste de Stroop , Adulto Jovem
9.
World Neurosurg ; 152: e32-e44, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33872837

RESUMO

OBJECTIVE: Coherence between the hippocampus and other brain structures has been shown with the theta frequency (3-8 Hz). Cortical decreases in theta coherence are believed to reflect response accuracy efficiency. However, the role of theta coherence during conflict resolution is poorly understood in noncortical areas. In this study, coherence between the hippocampus and orbitofrontal cortex (OFC) was measured during a conflict resolution task. Although both brain areas have been previously implicated in the Stroop task, their interactions are not well understood. METHODS: Nine patients were implanted with stereotactic electroencephalography contacts in the hippocampus and OFC. Local field potential data were sampled throughout discrete phases of a Stroop task. Coherence was calculated for hippocampal and OFC contact pairs, and coherence spectrograms were constructed for congruent and incongruent conditions. Coherence changes during cue processing were identified using a nonparametric cluster-permutation t test. Group analysis was conducted to compare overall theta coherence changes among conditions. RESULTS: In 6 of 9 patients, decreased theta coherence was observed only during the incongruent condition (P < 0.05). Congruent theta coherence did not change from baseline. Group analysis showed lower theta coherence for the incongruent condition compared with the congruent condition (P < 0.05). CONCLUSIONS: Theta coherence between the hippocampus and OFC decreased during conflict. This finding supports existing theories that theta coherence desynchronization contributes to improved response accuracy and processing efficiency during conflict resolution. The underlying theta coherence observed between the hippocampus and OFC during conflict may be distinct from its previously observed role in memory.


Assuntos
Conflito Psicológico , Hipocampo/fisiologia , Negociação/psicologia , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Adulto , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/psicologia , Epilepsia Resistente a Medicamentos/cirurgia , Eletrodos Implantados , Eletroencefalografia/métodos , Eletroencefalografia/tendências , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
10.
J Neural Eng ; 17(6)2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33059331

RESUMO

Objective. Identify the role of beta-band (13-30 Hz) power modulation in the human hippocampus during conflict processing.Approach. We investigated changes in the spectral power of the beta band (13-30 Hz) as measured by depth electrode leads in the hippocampus during a modified Stroop task in six patients with medically refractory epilepsy. Previous work done with direct electrophysiological recordings in humans has shown hippocampal theta-band (3-8 Hz) modulation during conflict processing. Local field potentials sampled at 2 k Hz were used for analysis and a non-parametric cluster-permutationt-test was used to identify the time period and frequency ranges of significant power change during cue processing (i.e. post-stimulus, pre-response).Main results. In five of the six patients, we observe a statistically significant increase in hippocampal beta-band power during successful conflict processing in the incongruent trial condition (cluster-based correction for multiple comparisons,p< 0.05). There was no significant beta-band power change observed during the cue-processing period of the congruent condition in the hippocampus of these patients.Significance. The beta-power changes during conflict processing represented here are consistent with previous studies suggesting that the hippocampus plays a role in conflict processing, but it is the first time that the beta band has been shown to be involved in humans with direct electrophysiological evidence. We propose that beta-band modulation plays a role in successful conflict detection and automatic response inhibition in the human hippocampus as studied during a conflict response task.


Assuntos
Epilepsia Resistente a Medicamentos , Eletroencefalografia , Eletroencefalografia/métodos , Hipocampo/fisiologia , Humanos , Teste de Stroop
11.
Neurosurg Focus ; 49(1): E4, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32610288

RESUMO

OBJECTIVE: Motor brain-computer interface (BCI) represents a new frontier in neurological surgery that could provide significant benefits for patients living with motor deficits. Both the primary motor cortex and posterior parietal cortex have successfully been used as a neural source for human motor BCI, leading to interest in exploring other brain areas involved in motor control. The amygdala is one area that has been shown to have functional connectivity to the motor system; however, its role in movement execution is not well studied. Gamma oscillations (30-200 Hz) are known to be prokinetic in the human cortex, but their role is poorly understood in subcortical structures. Here, the authors use direct electrophysiological recordings and the classic "center-out" direct-reach experiment to study amygdaloid gamma-band modulation in 8 patients with medically refractory epilepsy. METHODS: The study population consisted of 8 epilepsy patients (2 men; age range 21-62 years) who underwent implantation of micro-macro depth electrodes for seizure localization and EEG monitoring. Data from the macro contacts sampled at 2000 Hz were used for analysis. The classic center-out direct-reach experiment was used, which consists of an intertrial interval phase, a fixation phase, and a response phase. The authors assessed the statistical significance of neural modulation by inspecting for nonoverlapping areas in the 95% confidence intervals of spectral power for the response and fixation phases. RESULTS: In 5 of the 8 patients, power spectral analysis showed a statistically significant increase in power within regions of the gamma band during the response phase compared with the fixation phase. In these 5 patients, the 95% bootstrapped confidence intervals of trial-averaged power in contiguous frequencies of the gamma band during the response phase were above, and did not overlap with, the confidence intervals of trial-averaged power during the fixation phase. CONCLUSIONS: To the authors' knowledge, this is the first time that direct neural recordings have been used to show gamma-band modulation in the human amygdala during the execution of voluntary movement. This work indicates that gamma-band modulation in the amygdala could be a contributing source of neural signals for use in a motor BCI system.


Assuntos
Tonsila do Cerebelo/fisiologia , Epilepsia/fisiopatologia , Movimento/fisiologia , Rede Nervosa/fisiologia , Encéfalo/fisiologia , Eletroencefalografia/métodos , Humanos , Córtex Motor/fisiologia , Lobo Parietal/fisiologia
12.
J Neural Eng ; 17(3): 036022, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32413878

RESUMO

OBJECTIVE: Characterize the role of the beta-band (13-30 Hz) in the human hippocampus during the execution of voluntary movement. APPROACH: We recorded electrophysiological activity in human hippocampus during a reach task using stereotactic electroencephalography (SEEG). SEEG has previously been utilized to study the theta band (3-8 Hz) in conflict processing and spatial navigation, but most studies of hippocampal activity during movement have used noninvasive measures such as fMRI. We analyzed modulation in the beta band (13-30 Hz), which is known to play a prominent role throughout the motor system including the cerebral cortex and basal ganglia. We conducted the classic 'center-out' direct-reach experiment with nine patients undergoing surgical treatment for medically refractory epilepsy. MAIN RESULTS: In seven of the nine patients, power spectral analysis showed a statistically significant decrease in power within the beta band (13-30 Hz) during the response phase, compared to the fixation phase, of the center-out direct-reach task using the Wilcoxon signed-rank hypothesis test (p < 0.05). SIGNIFICANCE: This finding is consistent with previous literature suggesting that the hippocampus may be involved in the execution of movement, and it is the first time that changes in beta-band power have been demonstrated in the hippocampus using human electrophysiology. Our findings suggest that beta-band modulation in the human hippocampus may play a role in the execution of voluntary movement.


Assuntos
Ritmo beta , Movimento , Córtex Cerebral , Eletroencefalografia , Hipocampo , Humanos
13.
World Neurosurg ; 139: e297-e307, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32298832

RESUMO

BACKGROUND: Stereotactic localization of neurosurgical targets traditionally relies on computed tomography (CT), which is considered the optimal imaging modality for geometric accuracy. However, in-depth investigations that characterize the precision and accuracy of CT images are lacking. We used a CT phantom to examine interscanner precision and interprotocol accuracy in coordinate localization. METHODS: A polymethylacrylate phantom was scanned with Toshiba Aquilion 64 and GE Healthcare LightSpeed 16 CT scanners, using both helical and incremental single-slice (SS) image acquisition protocols. The X, Y, and Z coordinates of 94 points across 6 surfaces of the phantom were physically measured. The CT scan-derived coordinates were compared with the phantom coordinates and with each other to determine accuracy and precision, respectively. RESULTS: Using the SS imaging protocol, the mean (SD) interscanner disparity in localization was 0.93 (0.39) mm, given by the average Euclidean distance between the coordinates of the 2 scanners. This discrepancy significantly varied by axis and surface, with the greatest discrepancy in the Z-axis of 0.30 mm (95% confidence interval, 0.25-0.35; P = 0.05) and on the superior surface of 1.30 mm (95% confidence interval, 1.15-1.45; P = 0.05). SS acquisition was significantly more accurate than the helical protocol. CONCLUSIONS: We found evidence of clinically relevant inconsistency between 2 CT scanners used for stereotactic localization. SS image acquisition was superior to helical scanning with respect to localization accuracy. Interscanner consistency cannot be assumed. Institutions would benefit from identifying the errors inherent in their CT scanners.


Assuntos
Imagens de Fantasmas , Técnicas Estereotáxicas/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
14.
rev. udca actual. divulg. cient ; 21(2): 565-572, jul.-dic. 2018. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1094758

RESUMO

RESUMEN Las aguas de desecho dispuestas en una corriente superficial, lagos, ríos, mar, sin ningún tratamiento, ocasionan graves inconvenientes de contaminación, que afectan la flora y la fauna. Estas aguas residuales, antes de ser vertidas en las masas receptoras, deben recibir un tratamiento adecuado, capaz de modificar sus condiciones físicas, químicas y microbiológicas, para evitar que su disposición cause la alteración y la degradación de los ecosistemas asociados y problemas de salud pública. La investigación tuvo como objetivo evaluar el efecto de mezclas de quitosano y extracto acuoso de la cáscara de naranja, a diferentes concentraciones, en el proceso de coagulación-floculación, de aguas residuales, para lo cual, se realizó una prueba de jarras con agitación rápida y lenta, para evaluar turbidez (NTU), demanda química de oxígeno (DQO), demanda bioquímica de oxígeno (DBO), sólidos suspendidos totales (SST) y SS (sólidos sedimentables). Los resultados mostraron que todos los tratamientos presentaron diferencias significativas (p<0,05), con la muestra control y fueron eficientes en la reducción de turbidez, DBO, DQO, SST, SS. El tratamiento que combinó quitosano y extracto acuoso de cáscara de naranja (50-50%), a un pH de 5,5, disminuyó significativamente (p<0,05) la turbidez, en 79%, demostrando, de manera preliminar, que el extracto acuoso de la cáscara de naranja acidifica la mezcla e incrementa la formación de flóculos aglomerados en una fase liviana de las muestras, convirtiéndose en un agente eficiente, para ser usado en el tratamiento de aguas residuales.


ABSTRACT Waste water disposed in a superficial current, lakes, rivers, the sea, without any treatment, causes great inconvenient pollution that affects the flora and fauna of a region. This wastewater, before being poured into the receiving body of water, must receive the appropriate treatment, in order to modify its physical, chemical and microbiological conditions, to avoid that its disposal causes the alteration and degradation of the associated ecosystems and problem with public health. This research had as an objective to assess the effect of chitosan and aqueous extract of orange peel shells at different concentrations on the coagulation-flocculation process of wastewater. In order to do this, a jar test with fast and slow pull was carried out, assessing turbidity (NTU), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS) and SS (solid sediments). The results showed that all the treatments presented significant differences (p<0.05) to the control sample, and were efficient in the decrease of NTU, DQO, DBO, SST, and SS. The treatment that combined chitosan and aqueous extract of orange peel (50-50%) at a pH or 5.5, decreased significantly (p<0.05) the turbidity in a 79%, showing in a preliminary way that the aqueous extract of orange peel shells acidifies the mix and increases the formation of agglomerated floccules in a light phase of the samples, becoming an efficient agent to be used in the treatment of wastewater.

15.
J Pers Assess ; 89 Suppl 1: S149-53, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18039154

RESUMO

This study is composed of 517 adult voluntary participants, from Barcelona and its surroundings, all of whom are from Spain, Barcelona, and Catalonia. The study builds on a previously published report for a smaller sample (N = 250; see Alvarez, Baeza, Campo, Garcia, Guardia, et al., 1993) and is the result of collaboration between students and professors at the Barcelona Rorschach School (Catalan Rorschach Society). Our aim is to offer local data that should help to understand possible differences with existing reference data for the Rorschach Comprehensive System (CS; Exner, 2005), which is the system that has been taught at this school since 1978. Inclusion and exclusion criteria are described and interrater reliability statistics at the response level are presented, along with scores for the CS, followed by a discussion and very brief comparison with other international reference samples.


Assuntos
Saúde Mental , Determinação da Personalidade/estatística & dados numéricos , Personalidade , Projetos de Pesquisa/normas , Teste de Rorschach/estatística & dados numéricos , Adulto , Idoso , Características Culturais , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Psicometria/estatística & dados numéricos , Valores de Referência , Reprodutibilidade dos Testes , Espanha/epidemiologia , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , População Urbana/estatística & dados numéricos
16.
Artigo | Index Psicologia - Periódicos | ID: psi-12628

RESUMO

Trata-se de um estudo psicanalitico de um paciente com impotencia sexual e depressao.


Assuntos
Teste de Rorschach , Psicanálise , Testículo , Apego ao Objeto , Teste de Rorschach , Psicanálise , Apego ao Objeto
17.
Virology ; 149(1): 74-82, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2418583

RESUMO

Glycoprotein gp3 (64K) is one of the major proteins specified by varicella-zoster virus (VZV). This glycoprotein was purified on an immunoadsorbent consisting of monoclonal antibody (clone 8) against gp3 linked to protein A-Sepharose. Rabbits were then immunized with the purified antigen to obtain monospecific antisera against gp3. The monospecific antisera and monoclonal antibody immunoprecipitated polypeptides with the same molecular weights of approximately 64,000 (64K), 106K, and 116K from a lysate of labeled cells infected with VZV. The monoclonal antibodies against gp3 did not have neutralizing activity against VZV, but anti-gp3 monospecific sera neutralized VZV infectivity. The antigenic relation of VZV to herpes simplex virus (HSV) was investigated by the immunofluorescent test, immunoprecipitation followed by analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the neutralizing antibody test with monoclonal antibodies and monospecific antisera. In the indirect immunofluorescent test, the cytoplasm of cells infected with HSV-type 1 or HSV-type 2 was stained with anti-gp3 monospecific antiserum but not with anti-gp3 monoclonal antibodies. This serum also precipitated the polypeptides of HSV-type 1 and HSV-type 2 with molecular weight of approximately 120,000, possibly corresponding to gB of HSV-1 or HSV-2, and this immunoprecipitation was blocked by anti-gB monoclonal antibody. However, anti-gp3 monospecific antisera did not neutralize either HSV-type 1 or HSV-type 2 infectivity. These results suggest that gp3 induces neutralizing antibody against VZV and that it also has a cross-reacting antigenic determinant with gB of HSV.


Assuntos
Antígenos Virais/imunologia , Glicoproteínas/imunologia , Herpesvirus Humano 3/imunologia , Simplexvirus/imunologia , Proteínas do Envelope Viral , Proteínas Virais/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , Linhagem Celular , Chlorocebus aethiops , Reações Cruzadas , Epitopos/imunologia , Imunofluorescência , Glicoproteínas/isolamento & purificação , Humanos , Soros Imunes/imunologia , Testes de Neutralização , Proteínas Virais/isolamento & purificação
18.
Virology ; 143(1): 252-9, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-2998004

RESUMO

Monoclonal antibodies to varicella zoster virus (VZV) glycoproteins were used to study the processing of three glycoproteins with molecular weights of 83K-94K (gp 2), 64K (gp 3), and 55K (gp 5). Immunoprecipitation experiments performed with VZV-infected cells, pulse labeled with [3H]glucosamine in the presence of tunicamycin, suggest that O-linked oligosaccharide is present on the glycoprotein of gp 2. Use of the enzyme endo-beta-N-acetylglucosaminidase H revealed that the fully processed form of gp 3 had high-mannose type and that of gp 5 had only complex type of N-linked oligosaccharides. Experiments with monensin suggest that the precursor form (116K) of gp 3 is cleaved during the processing from Golgi apparatus to cell surface membrane. The extension of O-linked oligosaccharide chain and the complex type of N-linked oligosaccharide chains also occurs during this processing.


Assuntos
Glicoproteínas/genética , Herpesvirus Humano 3/genética , Proteínas Virais/genética , Anticorpos Monoclonais , Eletroforese em Gel de Poliacrilamida , Embrião de Mamíferos , Feminino , Fibroblastos , Glicoproteínas/isolamento & purificação , Herpesvirus Humano 3/efeitos dos fármacos , Humanos , Peso Molecular , Gravidez , Radioimunoensaio , Radioisótopos de Enxofre , Trítio , Tunicamicina/farmacologia , Proteínas Virais/isolamento & purificação
20.
Rev. psicoanal ; 19(1 -2): 66-70, 1962.
Artigo em Espanhol | BINACIS | ID: biblio-1172637

Assuntos
Psicanálise
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