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1.
Cureus ; 14(7): e26550, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35815301

ABSTRACT

Background The deviation from perfect bilateral symmetry is defined as fluctuating asymmetry (FA) and is a common phenomenon among living organisms. This deviation from perfection is thought to reflect the environmental pressures experienced during development and, therefore, the FA represents an epigenetic measure of the environmental stress, which affects all living beings from conception, progressively affecting all aspects of life. Rinaldi and Fontani hypothesized that the FA morpho-functional changes are originated by an adaptive motor behavior determined by functional alterations in the cerebellum and neural circuits, not caused by a lesion, but induced by the experienced environmental stress. They identified in the asymmetric activation of symmetrical muscle groups, detectable even in healthy subjects, the expression of the dysfunctional adaptation state of the subject and named this clinical semeiotic phenomenon functional dysmetria (FD). On these premises, they developed the radio electric asymmetric conveyer (REAC) technology, a neuromodulation technology aimed at optimizing the best neuro-psycho-motor strategies in relation to environmental interaction. Neuro postural optimization (NPO) is a neurobiological stimulation treatment administered with the REAC technology and it has been specifically studied to treat the state of dysfunctional adaptation that is revealed through the presence of FD. Aim The purpose of this study was to verify whether a single administration of the REAC NPO treatment can trigger the improvement of the capacity of stress management and the quality of life in a population of children housed in a group home in Macapá, Brazil. Materials and methods The sample of this study consisted of nine children (six boys and three girls) in the age group of 6-11 years, which represented the totality of the children present in the structure. The children was investigated for the assessment of the presence of functional dysmetria and with the Pediatric Quality of Life Inventory TM 4.0 (PedsQL) before and one week after the administration of the REAC NPO. Results The stable disappearance of FD was found in all children at follow-up. In addition, improvements were found in stress management and quality of life, in the physical, emotional, social, and scholastic aspects evaluated with PedsQL. Conclusions It was seen that the REAC NPO neurobiological modulation treatment induced the stable disappearance of FD and triggered the initial improvement of neurophysical aspects also in a population of children housed in a group home in the Amazon region of Macapá, Brazil.

2.
Neurobiol Dis ; 86: 1-15, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26586558

ABSTRACT

Prolonged L-dopa treatment in Parkinson's disease (PD) often leads to the expression of abnormal involuntary movements known as L-dopa-induced dyskinesia. Recently, dramatic 80 Hz oscillatory local field potential (LFP) activity within the primary motor cortex has been linked to dyskinetic symptoms in a rodent model of PD and attributed to stimulation of cortical dopamine D1 receptors. To characterize the relationship between high gamma (70-110 Hz) cortical activity and the development of L-dopa-induced dyskinesia, cortical LFP and spike signals were recorded in hemiparkinsonian rats treated with L-dopa for 7 days, and dyskinesia was quantified using the abnormal involuntary movements (AIMs) scale. The relationship between high gamma and dyskinesia was further probed by assessment of the effects of pharmacological agents known to induce or modulate dyskinesia expression. Findings demonstrate that AIMs and high gamma LFP power increase between days 1 and 7 of L-dopa priming. Notably, high beta (25-35 Hz) power associated with parkinsonian bradykinesia decreased as AIMs and high gamma LFP power increased during priming. After priming, rats were treated with the D1 agonist SKF81297 and the D2 agonist quinpirole. Both dopamine agonists independently induced AIMs and high gamma cortical activity that were similar to that induced by L-dopa, showing that this LFP activity is neither D1 nor D2 receptor specific. The serotonin 1A receptor agonist 8-OH-DPAT reduced L-dopa- and DA agonist-induced AIMs and high gamma power to varying degrees, while the serotonin 1A antagonist WAY100635 reversed these effects. Unexpectedly, as cortical high gamma power increased, phase locking of cortical pyramidal spiking to high gamma oscillations decreased, raising questions regarding the neural substrate(s) responsible for high gamma generation and the functional correlation between high gamma and dyskinesia.


Subject(s)
Dyskinesia, Drug-Induced/physiopathology , Gamma Rhythm/drug effects , Levodopa/administration & dosage , Motor Cortex/drug effects , Motor Cortex/physiopathology , Parkinsonian Disorders/physiopathology , 8-Hydroxy-2-(di-n-propylamino)tetralin/administration & dosage , Animals , Benzazepines/administration & dosage , Disease Models, Animal , Dopamine Agonists/administration & dosage , Male , Motor Activity/drug effects , Neurons/drug effects , Neurons/physiology , Oxidopamine , Parkinsonian Disorders/chemically induced , Quinpirole/administration & dosage , Rats , Rats, Sprague-Dawley , Serotonin Receptor Agonists/administration & dosage
3.
J Neurosci ; 35(17): 6918-30, 2015 Apr 29.
Article in English | MEDLINE | ID: mdl-25926466

ABSTRACT

Oscillatory activity in both beta and gamma ranges has been recorded in the subthalamic nucleus (STN) of Parkinson's disease (PD) patients and linked to motor function, with beta activity considered antikinetic, and gamma activity, prokinetic. However, the extent to which nonmotor networks contribute to this activity is unclear. This study uses hemiparkinsonian rats performing a treadmill walking task to compare synchronized STN local field potential (LFP) activity with activity in motor cortex (MCx) and medial prefrontal cortex (mPFC), areas involved in motor and cognitive processes, respectively. Data show increases in STN and MCx 29-36 Hz LFP spectral power and coherence after dopamine depletion, which are reduced by apomorphine and levodopa treatments. In contrast, recordings from mPFC 3 weeks after dopamine depletion failed to show peaks in 29-36 Hz LFP power. However, mPFC and STN both showed peaks in the 45-55 Hz frequency range in LFP power and coherence during walking before and 21 days after dopamine depletion. Interestingly, power in this low gamma range was transiently reduced in both mPFC and STN after dopamine depletion but recovered by day 21. In contrast to the 45-55 Hz activity, the amplitude of the exaggerated 29-36 Hz rhythm in the STN was modulated by paw movement. Furthermore, as in PD patients, after dopamine treatment a third band (high gamma) emerged in the lesioned hemisphere. The results suggest that STN integrates activity from both motor and cognitive networks in a manner that varies with frequency, behavioral state, and the integrity of the dopamine system.


Subject(s)
Cognition Disorders/etiology , Functional Laterality/physiology , Motor Activity/physiology , Parkinsonian Disorders/complications , Parkinsonian Disorders/pathology , Subthalamic Nucleus/physiopathology , Wakefulness , Action Potentials/drug effects , Action Potentials/physiology , Adrenergic Agents/toxicity , Animals , Antiparkinson Agents/pharmacology , Benzazepines/pharmacology , Disease Models, Animal , Dopamine Antagonists/pharmacology , Evoked Potentials/drug effects , Evoked Potentials/physiology , Levodopa/therapeutic use , Male , Oxidopamine/toxicity , Parkinsonian Disorders/chemically induced , Parkinsonian Disorders/drug therapy , Rats , Rats, Long-Evans , Time Factors , Tyrosine 3-Monooxygenase/metabolism
4.
Exp Neurol ; 261: 563-77, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25084518

ABSTRACT

Exaggerated beta range (13-30Hz) synchronized activity is observed in the basal ganglia of Parkinson's disease (PD) patients during implantation of deep brain stimulation electrodes and is thought to contribute to the motor symptoms of this disorder. To explore the translational potential of similar activity observed in a rat model of PD, local field potentials (LFPs) and spiking activity in basal ganglia output were characterized in rats with unilateral dopamine cell lesion during a range of behaviors. A circular treadmill was used to assess activity during walking; hemiparkinsonian rats could maintain a steady gait when oriented ipsiversive to the lesioned hemisphere, but were less effective at walking when oriented contraversive to lesion. Dramatic increases in substantia nigra pars reticulata (SNpr) LFP oscillatory activity and spike-LFP synchronization were observed within the beta/low gamma range (12-40Hz) in the lesioned hemisphere, relative to the non-lesioned hemisphere, with the dominant frequency of spike-LFP entrainment and LFP power varying with behavioral state. At 3weeks postlesion, the mean dominant entrainment frequency during ipsiversive treadmill walking and grooming was 34Hz. Other behaviors were associated with lower mean entrainment frequencies: 27-28Hz during alert non-walking and REM, 17Hz during rest and 21Hz during urethane anesthesia with sensory stimulation. SNpr spike-LFP entrainment frequency was stable during individual treadmill walking epochs, but increased gradually over weeks postlesion. In contrast, SNpr LFP power in the 25-40Hz range was greatest at the initiation of each walking epoch, and decreased during walking to stabilize by 6min at 49% of initial values. Power was further modulated in conjunction with the 1.5s stepping rhythm. Administration of l-dopa improved contraversive treadmill walking in correlation with a reduction in SNpr 25-40Hz LFP power and spike synchronization in the dopamine cell lesioned hemisphere. These effects were reversed by the serotonergic 1A agonist, 8-OH-DPAT. While the prominent spike-LFP phase locking observed during ongoing motor activity in the hemiparkinsonian rats occurs at frequencies intriguingly higher than in PD patients, the synchronized activity in the SNpr of this animal model has much in common with oscillatory activity recorded from the basal ganglia of the PD patients. Results support the potential of this model for providing insight into relationships between synchronization of basal ganglia output induced by loss of dopamine and motor symptoms in PD.


Subject(s)
Basal Ganglia/physiopathology , Brain Waves/physiology , Functional Laterality/physiology , Parkinsonian Disorders/pathology , Parkinsonian Disorders/physiopathology , Action Potentials/drug effects , Action Potentials/physiology , Adrenergic Agents/toxicity , Animals , Antiparkinson Agents/pharmacology , Brain Waves/drug effects , Disease Models, Animal , Dopamine Antagonists/pharmacology , Levodopa/pharmacology , Male , Neural Pathways/injuries , Neural Pathways/physiology , Oxidopamine/toxicity , Parkinsonian Disorders/chemically induced , Parkinsonian Disorders/drug therapy , Piperazines/pharmacology , Pyridines/pharmacology , Rats , Rats, Long-Evans , Salicylamides/pharmacology , Serotonin Antagonists/pharmacology , Substantia Nigra/physiopathology
5.
Basal Ganglia ; 3(4): 221-227, 2014 Apr 01.
Article in English | MEDLINE | ID: mdl-25667820

ABSTRACT

Exaggerated beta range (15-30 Hz) oscillatory activity is observed in the basal ganglia of Parkinson's disease (PD) patients during implantation of deep brain stimulation electrodes. This activity has been hypothesized to contribute to motor dysfunction in PD patients. However, it remains unclear how these oscillations develop and how motor circuits become entrained into a state of increased synchronization in this frequency range after loss of dopamine. It is also unclear whether this increase in neuronal synchronization actually plays a significant role in inducing the motor symptoms of this disorder. The hemiparkinsonian rat has emerged as a useful model for investigating relationships between loss of dopamine, increases in oscillatory activity in motor circuits and behavioral state. Chronic recordings from these animals show exaggerated activity in the high beta/low gamma range (30-35 Hz) in the dopamine cell-lesioned hemisphere. This activity is not evident when the animals are in an inattentive rest state, but it can be stably induced and monitored in the motor cortex and basal ganglia when they are engaged in an on-going activity such as treadmill walking. This review discusses data obtained from this animal model and the implications and limitations of this data for obtaining further insight into the significance of beta range activity in PD.

6.
J Neurosci ; 32(23): 7869-80, 2012 Jun 06.
Article in English | MEDLINE | ID: mdl-22674263

ABSTRACT

Excessive beta frequency oscillatory and synchronized activity has been reported in the basal ganglia of parkinsonian patients and animal models of the disease. To gain insight into processes underlying this activity, this study explores relationships between oscillatory activity in motor cortex and basal ganglia output in behaving rats after dopamine cell lesion. During inattentive rest, 7 d after lesion, increases in motor cortex-substantia nigra pars reticulata (SNpr) coherence emerged in the 8-25 Hz range, with significant increases in local field potential (LFP) power in SNpr but not motor cortex. In contrast, during treadmill walking, marked increases in both motor cortex and SNpr LFP power, as well as coherence, emerged in the 25-40 Hz band with a peak frequency at 30-35 Hz. Spike-triggered waveform averages showed that 77% of SNpr neurons, 77% of putative cortical interneurons, and 44% of putative pyramidal neurons were significantly phase-locked to the increased cortical LFP activity in the 25-40 Hz range. Although the mean lag between cortical and SNpr LFPs fluctuated around zero, SNpr neurons phase-locked to cortical LFP oscillations fired, on average, 17 ms after synchronized spiking in motor cortex. High coherence between LFP oscillations in cortex and SNpr supports the view that cortical activity facilitates entrainment and synchronization of activity in basal ganglia after loss of dopamine. However, the dramatic increases in cortical power and relative timing of phase-locked spiking in these areas suggest that additional processes help shape the frequency-specific tuning of the basal ganglia-thalamocortical network during ongoing motor activity.


Subject(s)
Cortical Synchronization , Electroencephalography , Motor Cortex/physiology , Parkinson Disease, Secondary/physiopathology , Substantia Nigra/physiology , Animals , Antiparkinson Agents/pharmacology , Data Interpretation, Statistical , Dopamine/metabolism , Dopamine Antagonists/pharmacology , Electrodes, Implanted , Electromyography , Levodopa/pharmacology , Male , Membrane Potentials/drug effects , Membrane Potentials/physiology , Motor Activity/physiology , Motor Cortex/drug effects , Rats , Rats, Long-Evans , Rest/physiology , Substantia Nigra/drug effects , Walking/physiology
7.
J Neurophysiol ; 106(4): 2012-23, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21813748

ABSTRACT

Abnormal oscillatory synchrony is increasingly acknowledged as a pathophysiological hallmark of Parkinson's disease, but what promotes such activity remains unclear. We used novel, nonlinear time series analyses and information theory to capture the effects of dopamine depletion on directed information flow within and between the subthalamic nucleus (STN) and external globus pallidus (GPe). We compared neuronal activity recorded simultaneously from these nuclei in 6-hydroxydopamine-lesioned Parkinsonian rats with that in dopamine-intact control rats. After lesioning, both nuclei displayed pronounced augmentations of beta-frequency (∼20 Hz) oscillations and, critically, information transfer between STN and GPe neurons was increased. Furthermore, temporal profiles of the directed information transfer agreed with the neurochemistry of these nuclei, being "excitatory" from STN to GPe and "inhibitory" from GPe to STN. Separation of the GPe population in lesioned animals into "type-inactive" (GP-TI) and "type-active" (GP-TA) neurons, according to definitive firing preferences, revealed distinct temporal profiles of interaction with STN and each other. The profile of GP-TI neurons suggested their output is of greater causal significance than that of GP-TA neurons for the reduced activity that periodically punctuates the spiking of STN neurons during beta oscillations. Moreover, STN was identified as a key candidate driver for recruiting ensembles of GP-TI neurons but not GP-TA neurons. Short-latency interactions between GP-TI and GP-TA neurons suggested mutual inhibition, which could rhythmically dampen activity and promote anti-phase firing across the two subpopulations. Results thus indicate that information flow around the STN-GPe circuit is exaggerated in Parkinsonism and further define the temporal interactions underpinning this.


Subject(s)
Dopamine/deficiency , Dopaminergic Neurons/physiology , Globus Pallidus/physiopathology , Neural Pathways/physiopathology , Parkinsonian Disorders/physiopathology , Subthalamic Nucleus/physiopathology , Action Potentials , Animals , Dopamine/physiology , Dopamine Antagonists/toxicity , Male , Models, Neurological , Nerve Net/physiopathology , Nonlinear Dynamics , Oxidopamine/toxicity , Parkinsonian Disorders/chemically induced , Rats , Rats, Sprague-Dawley , Time Factors
8.
Anal Bioanal Chem ; 399(6): 2137-47, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20922517

ABSTRACT

This work compares the estimation of the particle size distribution of a pharmaceutical powder using near-infrared spectroscopy (NIRS), powder flowability properties, and components concentration. The estimations were made by considering the former data blocks separately and together using a multi-block approach. The powders were based on a formulation of paracetamol as the pharmaceutical active ingredient. The reference method used to determine particle size distribution was sieving. Partial least squares methods were used to estimate the multivariate regression models, and the results were compared in terms of figures of merit. It was shown that the partial least squares methods gave similar prediction errors. Regarding the data blocks used, the NIRS block was proven the most advantageous to estimate the particle size distribution. The prediction error of the NIRS block was similar to the other data blocks with additional advantages such as less generalization problems and the possibility of its use to predict additional physical and chemical properties with an improvement to analysis time. The multi-block approach produced the worst results but nevertheless allowed a deeper understanding of the individual contributions of the data blocks in the prediction of the particle size distribution.


Subject(s)
Pharmaceutical Preparations/chemistry , Powders/chemistry , Spectroscopy, Near-Infrared/methods , Least-Squares Analysis , Particle Size , Regression Analysis , Spectroscopy, Near-Infrared/statistics & numerical data
9.
J Pharm Biomed Anal ; 52(4): 484-92, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20167448

ABSTRACT

The physical properties of pharmaceutical powders are of upmost importance in the pharmaceutical industry. The knowledge of their flow properties is of critical significance in operations such as blending, tablet compression, capsule filling, transportation, and in scale-up operations. Powders flow properties are measured using a number of parameters such as, angle of repose, compressibility index (Carr's index) and Hausner ratio. To estimate these properties, specific and expensive equipment with time-consuming analysis is required. Near infrared spectroscopy is a fast and low-cost analytical technique thoroughly used in the pharmaceutical industry in the quantification and qualification of products. To establish the potential of this technique to determine the parameters associated with the flow properties of pharmaceutical powders, blended powders based on paracetamol as the active pharmaceutical ingredient were constructed in pilot scale. Spectra were recorded on a Fourier-transform near infrared spectrometer in reflectance mode. The parameters studied were the angle of repose, aerated and tapped bulk density. The correlation between the reference method values and the near infrared spectrum was performed by partial least squares and optimized in terms of latent variables using cross-validation. The near infrared based properties predictions were compared with the reference methods results. Prediction errors, which varied between 2.35% for the angle of repose, 2.51% for the tapped density and 3.18% for the aerated density, show the potential of NIR spectroscopy in the determination of physical properties affecting the flowability of pharmaceutical powders.


Subject(s)
Acetaminophen/analysis , Acetaminophen/chemistry , Spectroscopy, Near-Infrared , Pharmaceutical Preparations/analysis , Pharmaceutical Preparations/chemistry , Powders , Spectroscopy, Near-Infrared/methods , Technology, Pharmaceutical/methods
10.
J Neurophysiol ; 102(2): 1092-102, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19535481

ABSTRACT

Dopamine depletion in cortical-basal ganglia circuits in Parkinson's disease (PD) grossly disturbs movement and cognition. Classic models relate Parkinsonian dysfunction to changes in firing rates of basal ganglia neurons. However, disturbances in other dynamics of neural activity are also common. Taking both inappropriate firing rates and other dynamics into account and determining how changes in the properties of these neural circuits that occur during PD impact on information coding are thus imperative. Here, we examined in vivo network dynamics in the external globus pallidus (GPe) of rats before and after chronic dopamine depletion. Dopamine depletion led to decreases in the firing rates of GPe neurons and increases in synchronized network oscillations in the beta frequency (13-30 Hz) band. Using logistic regression models, we determined the combined and separate impacts of these factors on network entropy, a measure of the upper bound of information coding capacity. Importantly, changes in these features in dopamine-depleted rats led to a significant decrease in GPe network entropy. Changes in firing rates had the largest impact on entropy, with changes in synchrony also decreasing entropy at the network level. Changes in autocorrelations tended to offset these effects because autocorrelations decreased entropy more in the control animals. Thus it is possible that reduced information coding capacity within basal ganglia networks may contribute to the behavioral deficits accompanying PD.


Subject(s)
Dopamine/deficiency , Globus Pallidus/physiology , Globus Pallidus/physiopathology , Models, Neurological , Neurons/physiology , Parkinsonian Disorders/physiopathology , Action Potentials/physiology , Adrenergic Agents/toxicity , Analysis of Variance , Animals , Dopamine/metabolism , Logistic Models , Male , Microelectrodes , Neurons/drug effects , Oxidopamine/toxicity , Periodicity , Rats , Rats, Sprague-Dawley , Substantia Nigra/drug effects , Substantia Nigra/injuries , Time Factors
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