RESUMO
Thousand-year-old Buddhist traditions have developed a wide range of methods for the subjective exploration of consciousness through meditation. Combining their subjective research with the possibilities of modern neuroscience can help us better understand the physiological mechanisms of consciousness. Therefore, we have been guided by specifically Buddhist explanations when studying the physiological mechanisms of altered states of consciousness during Buddhist meditations. In Buddhism, meditations are generally divided into two large categories: (1) one-pointed concentration and (2) analytical meditation. Maintaining both one-pointed concentration and analytical meditation on 'bodhicitta' ("the thought of awakening") and 'emptiness' is a necessary condition for transitioning into tantric practices. Tantric practices involve sophisticated visualizations of Buddhist deities, the 'energy structure' of the human body, and the visualization of the stage-by-stage process of dying accompanied with the dissolution of body elements. According to Buddhism, these meditations are characterized by the gradual withdrawal from "gross levels" of consciousness associated with the five senses. From a psychophysiological perspective, this withdrawal of sensory consciousness can be considered as the decrease of sensory stimuli recognition and attentional disengagement from the external world. We concentrated on how considered meditations affect sensory and cognitive processing of external stimuli. Auditory event-related potentials (ERPs) in the passive oddball paradigm were studied both during meditations and in a controlled state of relaxed wakefulness. It was shown with a group of 115 Buddhist monks that during meditation, mismatch negativity amplitudes, amplitudes of N1 and P2 components of ERPs to deviant stimuli, and the amplitudes of the P3a component to novel stimuli all decrease. These outcomes suggest that the considered Buddhist meditations, compared to the control state of relaxed wakefulness, are accompanied by a decrease in physiological processes responsible for maintaining attention on the outside world and recognizing changes in the stream of sensory stimuli.
Assuntos
Meditação , Monges , Atenção/fisiologia , Budismo/psicologia , Potenciais Evocados , Humanos , Meditação/métodosRESUMO
The article describes a clinical case of successful chemotherapeutic and radiation treatment of a patient with breast cancer and metastases to the brain and meninges and with a pronounced neurological deficit. The patient underwent combined treatment (whole brain radiation with TBD of 30 Gy and local radiation of a metastasis with TBD of 15 Gy associated with capecitabine therapy) with continued administration of capecitabine until improvement. A partial metastasis reduction by 50% and complete regression of the neurological deficit were observed. Disease-free period was 1 year and 10 months, and the overall survival amounted to 2 years.
Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Capecitabina/administração & dosagem , Quimiorradioterapia , Neoplasias Meníngeas , Adulto , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Feminino , Humanos , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/secundário , Neoplasias Meníngeas/terapia , Metástase NeoplásicaRESUMO
The aim of the present study was to investigate EMG contamination on high-frequency scalp electroencephalogram (EEG) during comparisons of certain cognitive tasks performance. 19 healthy women who performed similar test tasks before and after cosmetic injections of Dysport in various face regions for reduction of facial muscles activity took part in the study. The test tasks were focused on induction of emotional states with different valences, on memory storing and extraction of verbal information. Default state of rest was uncluded too. During performance of the tasks, parallel registrations of EEG from a scalp surface(19 channels) and EMG from several facial muscles (6 channels) were carried out. Changes of spectral power in ß2 and low γ frequency ranges (18-40 Hz) in EEG- and EMG-derivations after Dysport injections were analyzed. Changes of spectral power in the same derivations during comparisons of the different test tasks were analyzed before and after Dysport injections separately. It was demonstrated that Dysport injections lead to reduction of EMG power in regions of injections and to reduction of EEG power in frontal and temporal derivations. However, the EEG-correlates revealed when comparing different test tasks remain qualitatively invariable both after, and before Disports injections. These facts confirmed that EMG makes a noticeable contribution to the electric activity registered from a scalp in the frequency ranges more than 18-Hz. At the same time, it was shown that in certain experimental situations influence of EMG not necessarily interferes with identification of EEG-correlates of mental activity during EEG registration from a head surface in ß2 and low γ frequency ranges.
Assuntos
Eletroencefalografia , Eletromiografia , Emoções , Músculos Faciais , Toxinas Botulínicas Tipo A , Músculos Faciais/fisiopatologia , Feminino , Humanos , Memória , Análise e Desempenho de TarefasRESUMO
Application of modern linear electron accelerators, equipped with precise navigation systems, maximum conformal dose delivery as well as imaging of irradiated focus significantly increased possibilities of escalating of doses of ionizing radiation in a selected volume with the necessary protection of the surrounding critical structures. These technological solutions and modern ideas about possibilities of remote beam radiation therapy resulted in a significant increase of the role of radiation therapy and, in particular, stereotactic radiotherapy in the treatment of patients with liver metastases. This technique allows creating locally in metastatic tumor site a high dose of ionizing radiation causing by that the destruction of the tumor. This promising direction in treatment of liver metastases significantly expanded possibilities of complex treatment and enabled us to provide specific assistance to those patients who have been rejected from other methods of treatment.
Assuntos
Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Radiocirurgia , Radioterapia Conformacional/métodos , Adulto , Idoso , Feminino , Humanos , Neoplasias Hepáticas/radioterapia , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Técnicas Estereotáxicas , Resultado do TratamentoRESUMO
Morbidity and mortality from pancreatic cancer is steadily increasing. Resectable cases are not more than 20%. Conventional schemes of chemoradiation and radiation therapy are durable over the time, have toxicity and low treatment outcomes. Many foreign authors consider as promising the technique of stereotactic radiotherapy, which is often used in pancreatic cancer and permit achieving high local control. At our institution there has been developed and introduced into clinical practice a method of stereotactic radiotherapy for the palliative treatment of patients with pancreatic cancer, which improved not only the duration but also the quality of life of patients.
Assuntos
Cuidados Paliativos/métodos , Neoplasias Pancreáticas/cirurgia , Qualidade de Vida , Radiocirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico por imagem , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
There was performed a comparative analysis of the indicators of immediate and long-term results of chemoradiotherapy in 342 patients with squamous cell oropharyngeal carcinoma depending on hemoglobin level before and after treatment. In patients with normal level of hemoglobin a rate of response to treatment was almost two times higher than that of patients with anemia (75,3% vs. 23,5%) and complete regression of tumors was detected by more than three times often (65,4% vs. 17,6%). The overall five-year survival of patients with anemia was significantly worse than that of patients who had normal hemoglobin level (50,7% vs. 67,7%). Patients who had normal hemoglobin level at the time of discharge demonstrated a five-year overall survival of 75,7%, while those with a hemoglobin level below normal, but more than 80 g/l,--only 57,8%. Hemoglobin concentration was a significant prognostic factor for survival of patients with squamous cell carcinoma of the oral cavity and oropharynx. Low baseline of hemoglobin was also a negative prognostic factor for tumor response to treatment, especially to chemotherapy.
Assuntos
Anemia Hipocrômica/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Hemoglobinas/metabolismo , Neoplasias Orofaríngeas/terapia , Adulto , Idoso , Anemia Hipocrômica/sangue , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/sangue , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Valor Preditivo dos Testes , Prognóstico , Análise de SobrevidaRESUMO
Since February 2012, in order to increase the effectiveness of treatment and quality of life of patients with disseminated disease, there was developed and implemented a method of stereotactic radiotherapy for metastatic lesion of lungs by tumors of different histological types. 20 patients were treated by stereotactic radiotherapy ROD 7 Gy in five sessions during 5 days. There were evaluated results of treatment and prospects of this method.
Assuntos
Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Qualidade de Vida , Técnicas Estereotáxicas , Adulto , Idoso , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia/métodos , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
The present paper dedicated to the research of the functional interactions between brain structures while executing deliberate deceptive actions. Based on our own and literature data, we formulated the hypothesis that the functional interaction between brain areas responsible for the executive control, localized in the prefrontal cortex (inferior frontal gyrus), and the elements of error detection brain system, underlies deception. To test this hypothesis, we applied an analysis of the psychophysiological interaction (PPI), which revealed that the false actions (in comparison with true honestones) associated with increased functional connectivity between the left caudate nucleus and the left inferior frontal gyrus. Obtained experimental data support our hypothesis that the interaction of neural brain systems, which are responsible for executive control and error detection, underpins the brain maintenance of the execution of deceptive actions.
Assuntos
Núcleo Caudado/fisiologia , Enganação , Córtex Pré-Frontal/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , MasculinoRESUMO
Brain metastases in breast cancer develop for 24-32 months after the detection of the primary tumor. The study included patients with brain metastases who were divided into three groups: the first group--with early chemoradiotherapy (CRT) without induction chemotherapy (IC) by capecitabine; the second group--with delayed CRT with 4 or 8 courses of IC by capecitabine; the third group (a historical control) who received only whole brain radiation therapy. The median time to progression of intracranial metastases was 15.3, 12 and 5 months, respectively. The median time to the intracranial progression significantly less in the third group (5 months) compared with the first (15.3 months) (p = 0.0007) and the second (12 months) (p = 0.027) groups. The overall survival rate was 22.1, 15.1 and 6.8 months in three groups, respectively.
Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/terapia , Neoplasias da Mama/terapia , Capecitabina/administração & dosagem , Quimiorradioterapia Adjuvante , Irradiação Craniana , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Federação Russa/epidemiologia , Análise de Sobrevida , Fatores de Tempo , Resultado do TratamentoRESUMO
In the light of alternative conceptions of "two-system" and "single-system" models of language processing the efforts have been undertaken to study brain mechanisnis for generation of regular and irregular forms of Russian verbs. The 19 EEG channels of evoked activity were registered along with casual alternations of speech morphology operations to be compared. Verbs of imperfective aspect in the form of an infinitive, belonging either to a group of productive verbs (default, conventionally regular class), or toan unproductive group of verbs (conventionally irregular class) were presented to healthy subjects. The subjects were requested to produce first person present time forms of these verbs. Results of analysis of event related potentials (ERP) for a group of 22 persons are presented. Statistically reliable ERP amplitude distinctions between the verb groups are found onlyin the latencies 600-850 ms in central and parietal zones of the cortex. In these latencies ERP values associated with a presentation of irregular verbs are negative in relation to ERP values associated with the presentation of regular verbs. The received results are interpreted as a consequence of various complexity of mental work with verbs of these different groups and presumably don't support a hypothesis of universality of the "two-system" brain mechanism for processing of the regular and irregular language forms.
Assuntos
Córtex Cerebral/fisiologia , Potenciais Evocados Auditivos/fisiologia , Idioma , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Federação Russa , Fala/fisiologiaRESUMO
For many years the modern methods of functional tomographic brain imaging (fMRI and PET) were actively used not only for the research of basic brain functions, but also in clinical practice. In present paper we described the basic characteristics of the signal registered with fMRI and PET, the principles of image reconstruction, as well as the methodological requirements, which are necessary to obtain reliable results. The advantages and limitations of modem tomographic methods of the brain functions investigation are discussed. The need of the complex approach use in brain study is emphasized and methods for the study of functional integration of the brain are suggested.
Assuntos
Encéfalo/fisiologia , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Encéfalo/patologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/instrumentação , Imagem Multimodal/instrumentação , Neuroimagem/instrumentaçãoRESUMO
In this paper possible mechanism of improvement of the functional state of the brain areas, maintaining movement, visual, auditory, and higher functions of the brain during correction of generalized spastic syndrome (botulinotherapy with Xeomin) in patients in a vegetative state (VS) is discussed. If to consider the vegetative state as stable pathological condition (SPC) of the brain, then from the perspective of the theory of structural and functional organization of the brain with systems with rigid and flexible elements (N.P. Behtereva), the therapy led to an unbalance of SPC, "functional release" of neurons and redistribution of their functions to provide other activities, the formation of new interneuronal connections. Taking into account the functional variability of neurons (S.V. Medvedev), blocking neuromuscular transmission in spastic muscles leads to a reduction of abnormal afferent and efferent hyperactivity of motor and sensory neuronal circuits, which releases the brain for other activities. This allows to consider botulinotherapy of pharmacoresistant muscle spasticity in patients in VS and minimal consciousness, not only as a symptomatic treatment, but also as a "indirect neuroprotection".
Assuntos
Encéfalo/fisiopatologia , Neurônios , Estado Vegetativo Persistente/fisiopatologia , Estado de Consciência/fisiologia , Humanos , Movimento , Espasticidade Muscular/fisiopatologia , Neurônios/patologia , Neurônios/fisiologiaRESUMO
In the present article it was shown that the functional connectivity of brain structures, revealed by factor analysis of resting PET CBF and rCMRglu data, is an adequate tool to study the default mode of the human brain. The identification of neuroanatomic systems of default mode (default mode network) during routine clinical PET investigations is important for further studying the functional organization of the normal brain and its reorganizations in pathological conditions.
Assuntos
Mapeamento Encefálico , Encéfalo , Rede Nervosa , Adolescente , Adulto , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Feminino , Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiologia , Rede Nervosa/fisiopatologia , Neuroanatomia , Tomografia por Emissão de Pósitrons , Radiografia , Descanso/fisiologiaRESUMO
In the present article the features of the functional activity of the anterior cingulate cortex (ACC), a key element of neuroanatomical brain system of an error detection, in drug-resistant forms of obsessive-compulsive disorder (OCD) are discussed on a basis of both original and literature data. Available data indicate the presence of functional deficit in the ACC during OCD. This allows to suggest that functions of the ACC in OCD patient are partially redistributed between other brain areas. Thus in contrast to the previously accepted notion, the ACC as the target ofstereotactic surgery for OCD is pathologically altered brain region. Probably this is the reason why stereotactic destruction of ACC does not lead to significant changes in the patient's psyche. The essence of the pathological reorganisation of the functional activity of the brain in OCD remains unclear and requires further investigation.
Assuntos
Mapeamento Encefálico , Giro do Cíngulo/fisiopatologia , Transtorno Obsessivo-Compulsivo , Resistência a Medicamentos/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Humanos , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/psicologia , Transtorno Obsessivo-Compulsivo/cirurgia , Radiografia , Técnicas EstereotáxicasRESUMO
Mechanisms of HIV transportation through blood-brain barrier, vascular plexus and interaction with cerebral cells having CD-4-receptors, CCR-5- and CXCR-4-coreceptors were studied. Cerebral damage developed through latent and acute periods also known as HIV-encephalopathy, HIV-associated neurocognitive dysfunction etc. Cerebral lesions are caused by a variety of chemical agents from pro-inflammatory cytokines to toxic HIV-proteins resulting in development of HIV-dementia through several years. Even early stage of this process revealed significant disturbances of glucose metabolism and evoked potentials EEG alterations which can serve as a marker of HIV-infection. Genetic differences of HIV in blood and spinal liquor with different drug resistance were revealed implying a new approach to therapy development.
Assuntos
Complexo AIDS Demência , Fármacos Anti-HIV/uso terapêutico , Barreira Hematoencefálica , Sistema Nervoso Central , Infecções por HIV/complicações , HIV , Complexo AIDS Demência/diagnóstico , Complexo AIDS Demência/tratamento farmacológico , Complexo AIDS Demência/fisiopatologia , Complexo AIDS Demência/virologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Barreira Hematoencefálica/virologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiopatologia , Sistema Nervoso Central/virologia , Farmacorresistência Viral/genética , HIV/genética , HIV/fisiologia , Humanos , Prognóstico , Carga Viral/efeitos dos fármacos , Fenômenos Fisiológicos Virais/efeitos dos fármacos , Fenômenos Fisiológicos Virais/genéticaRESUMO
AIM: Study of specter of low-manifest infections (LMI) with central nervous system (CNS) damage and their role in patients in prolonged unconscious state (PUS) of noninflammatory etiology. MATERIALS AND METHODS: 32 patients (23 male, 9 female; age 14-58) in PUS of various etiology were examined. The main group (18 patients) received therapy against all infectious diseases including LMI; control group (14 patients)--only against common and nosocomial microflora. Patients were immunologically, infectologically and neurologically examined in dynamic. The data obtained were treated by using STATISTICA for Windows (version 5.5). RESULTS: Significant differences in immune and infectologic status depending on the nature of primary CNS damage were not detected. Immunodeficiency was detected in all patients; 94% of patients had increased non-specific IgM and IgE. Among LMI agents Chlamydia spp. were predominant. Cultural and/or PCR methods detected this microorganism during the primary examination in cerebrospinal fluid samples in 56% patients and in blood samples in 56%; during the second diagnostics or autopsy--only in 13 and 25%, respectively. Detection of Bacteroides fragilis, Human Herpes Virus (HHV-6), Virus Epstein Barr (VEB), Cytomegalovirus (CMV) in cerebrospinal fluid, blood and on mucous membranes of nasopharynx and conjunctiva was grouped more frequently with the presence of Chlamydia spp. in the CNS (p < 0.05) than with other LMI agents. Sanation of CNS from LMI was significantly accompanied by regeneration of communicative activity in comparison with the control group. CONCLUSION: In patients with PUS high frequency of CNS infection by various LMI agents and primarily Chlamydia spp. should be considered. Sanation from LMI can become a "window" for effective neuro-regenerative treatment.
Assuntos
Infecções Bacterianas/diagnóstico , Infecções do Sistema Nervoso Central/diagnóstico , Chlamydia/isolamento & purificação , Coinfecção , Inconsciência/diagnóstico , Viroses/diagnóstico , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antivirais/administração & dosagem , Infecções Bacterianas/líquido cefalorraquidiano , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/virologia , Bacteroides fragilis/genética , Bacteroides fragilis/isolamento & purificação , Sistema Nervoso Central/microbiologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/virologia , Infecções do Sistema Nervoso Central/líquido cefalorraquidiano , Infecções do Sistema Nervoso Central/tratamento farmacológico , Infecções do Sistema Nervoso Central/microbiologia , Infecções do Sistema Nervoso Central/virologia , Chlamydia/genética , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , DNA Bacteriano/análise , DNA Viral/análise , Feminino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Reação em Cadeia da Polimerase , Inconsciência/líquido cefalorraquidiano , Inconsciência/tratamento farmacológico , Inconsciência/microbiologia , Inconsciência/virologia , Viroses/líquido cefalorraquidiano , Viroses/tratamento farmacológico , Viroses/microbiologia , Viroses/virologiaRESUMO
In present research, the brain maintenance of the error detection mechanism was studied in resting condition and while subjects consciously implemented incorrect actions (i.e. deception). Assessment of the regional cerebral blood flow revealed involvement of anterior cingulated cortex in deception. The obtained data indicate that it is impossible to consciously control the activity of the error detection mechanism. PET study of patients with obsessive compulsive disorder in resting condition revealed a decrease of brain glucose metabolism in the anterior cingulated cortex in comparison with healthy subjects. These data pointed to malfunctioning of the error detection mechanism. The findings support the formerly proposed hypothesis about the impact of the error detection mechanism in formation and support of obsessive compulsive disorder.
Assuntos
Encéfalo/fisiologia , Enganação , Transtorno Obsessivo-Compulsivo/fisiopatologia , Adulto , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/fisiologia , Circulação Cerebrovascular/fisiologia , Lobo Frontal/irrigação sanguínea , Lobo Frontal/fisiologia , Glucose/metabolismo , Humanos , Tomografia por Emissão de Pósitrons/métodos , Fluxo Sanguíneo Regional/fisiologiaRESUMO
Complex examination of 25 patients in vegetative state was performed before and after correction of secondary brain damage. Catamnesis over a period of at least 6 months was traced. Preliminary results showed that better recovery of consciousness and cognitive functions was observed if before treatment diffuse glucose hypometabolism was significantly more widespread than morphological changes. Minimal positive dynamics was detected in cases in which the reduction of glucose metabolism was minimal. This and other paradoxical results become explainable if to consider vegetative state as stable pathological state of the brain. This open new approaches to treatment of this group of patients.