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1.
Georgian Med News ; (346): 14-20, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38501615

RESUMEN

In neurodegenerative diseases, particularly in Parkinson's disease (PD), antinociceptive centers are often implicated in neurodegeneration, leading to persistent pain unresponsive to narcotic substances. This study investigated the periaqueductal gray matter (PAG) and the nucleus raphe magnus (NRM), components of the brain's antinociceptive system. In conditions of rotenone intoxication (an experimental PD model), morphological changes in intracellular structures were observed in PAG and NRM neurons, indicating metabolic disorders characteristic of PD (alterations in the shape and size of neuronal bodies and processes, disruption of acid phosphatase activity in neuron cytoplasm). Under the influence of bacterial melanin and in combination with synoestrol, positive changes in structural properties were observed in PAG and NRM neurons compared to the rotenone model of PD. This included the preservation of the morphological characteristics typical of these brain regions, with cells exhibiting shapes and sizes close to normal. Furthermore, under the influence of these therapeutic agents, an increase in phosphatase activity in cell cytoplasm was detected, indicating an acceleration of metabolic processes (metabolic activation) disrupted by rotenone intoxication. The data obtained suggests that bacterial melanin and synoestrol may act as potential neuroprotective agents against PAG and NRM neurons in the rat brain in the rotenone model of PD. Further research is needed to elucidate the mechanisms of action of therapeutic doses and propose their use in the treatment of PD, either in isolation or combination therapy.


Asunto(s)
Enfermedad de Parkinson , Núcleos del Rafe , Animales , Núcleos del Rafe/fisiología , Enfermedad de Parkinson/tratamiento farmacológico , Rotenona/farmacología , Rotenona/análisis , Melaninas/análisis , Analgésicos
2.
Zh Vopr Neirokhir Im N N Burdenko ; 86(2): 103-108, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35412719

RESUMEN

OBJECTIVE: To demonstrate own experience in 3D modeling for planning of minimally invasive approach to the orbit and anterior skull base. MATERIAL AND METHODS: A 17-year-old patient admitted to the Department of Pediatric Neurosurgery with complaints of decreased visual acuity of the left eye, lacrimation and exophthalmos. MRI revealed a tumor of the left orbit. We have preoperatively modeled frontoorbital region, anterior skull, as well as eyeball and tumor within the same model. Considering young age and potentially favorable prognosis of disease, we preferred a minimally invasive intervention (microsurgical resection of tumor through minimally invasive frontoorbital access). RESULTS: Total resection of tumor was followed by examination of anterior skull base. There was postoperative regression of visual disturbances, lacrimation and exophthalmos. Sutures were removed after 5 days, and the patient was discharged. CONCLUSION: Minimally invasive frontoorbital access is adequate for approach to the orbit, anterior and middle cranial fossa, adequate resection of orbital tumor and examination of anterior skull base. 3D modeling is an additional preoperative tool to improve the quality of preoperative planning and facilitate intraoperative navigation.


Asunto(s)
Exoftalmia/cirugía , Órbita/cirugía , Neoplasias Orbitales/cirugía , Adolescente , Niño , Fosa Craneal Media , Exoftalmia/diagnóstico por imagen , Exoftalmia/etiología , Humanos , Imagenología Tridimensional , Procedimientos Quirúrgicos Mínimamente Invasivos , Procedimientos Neuroquirúrgicos , Órbita/diagnóstico por imagen , Neoplasias Orbitales/diagnóstico por imagen
3.
Artículo en Ruso | MEDLINE | ID: mdl-33864672

RESUMEN

Multiple gliomas are determined by synchronous two or more tumors located in different brain regions. It is important to distinguish multiple primary tumors and metastatic brain lesion. In the first case, tumor spread can`t be explained by dissemination along the cerebrospinal fluid pathways, commissural fibers or local metastases. Multiple primary tumors with different histological structures are called bidermal neoplasms. Surgery is preferred in these patients with severe symptoms. The purpose of surgery is maximum resection of tumor. Follow-up may be advisable for small tumors without clinical manifestations. Treatment of multiple gliomas includes surgery, radiotherapy and chemotherapy. Multiple tumor process in children is much more severe compared to a single neoplasia that requires neurological and neuroimaging control and determines treatment strategy. The authors report 3 children with multicentric gliomas, discuss the various aspects of diagnosis and treatment of multiple gliomas and formulate the recommendations for the treatment based on own clinical experience and literature data.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neurocirugia , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Niño , Glioma/diagnóstico por imagen , Glioma/cirugía , Humanos , Imagen por Resonancia Magnética , Procedimientos Neuroquirúrgicos
4.
Artículo en Ruso | MEDLINE | ID: mdl-33306301

RESUMEN

Currently, 3D-printing technologies are increasingly used in neurosurgery. Active development of this approach is valuable to improve preoperative planning, intraoperative navigation, and manufacturing of realistic training models. In this manuscript, the authors report an experience of the pediatric neurosurgical department of the Almazov National Medical Research Center regarding 3D-printing technologies in manufacturing of individual implants for skull defect closure. The main aspects of this technology, advantages and disadvantages are considered. Moreover, the authors describe several cases of creating individual implants for children with skull defects of various origins, dimensions and complexity.


Asunto(s)
Neurocirugia , Cráneo , Niño , Humanos , Procedimientos Neuroquirúrgicos , Impresión Tridimensional , Tecnología
5.
Artículo en Ruso | MEDLINE | ID: mdl-33095530

RESUMEN

OBJECTIVE: To analyze the causes of ineffective operations and the results of redo surgery in children with recurrent epileptic seizures. MATERIAL AND METHODS: The results of redo surgery were analyzed in 41 (10.6%) out of 387 children with drug resistant epilepsy treated surgically at the Russian Polenov Neurosurgical Institute for the period from 1994 to 2014. Patients with recurrent epilepsy after temporal resection (n=20), extratemporal resection (n=7), multifocal resection (n=6), callosotomy and stereotaxic destruction (n=8) were selected for analysis. RESULTS: Seizure-free period ranged from early postoperative period to 4 years. According to MRI data, lesions were not completely resected during primary surgery in 23 (56.1%) children. The causes of inefficiency of primary operations were inaccurate identification of epileptic focus in 15 (36.6%) patients; incomplete resection of epileptogenic and / or epileptic foci or incomplete disconnection of paroxysmal activity distribution pathways in 14 (34.1%) cases; epileptic foci de novo in 8 (19.5%) cases; inadequate surgical strategy in 4 (9.8%) patients. Redo surgery usually implied an extended previous resection in 34 (82.9%) patients. Engel I outcome after 3 years was achieved in 41.1% of patients, after 5 years - 38.3%, after 10 years - 36.4%. CONCLUSION: Redo surgery is quite effective and minimally traumatic. Therefore, patients with recurrent epileptic seizures should be considered as candidates for repeated operations if previous interventions turned out to be ineffective.


Asunto(s)
Epilepsia , Procedimientos Neuroquirúrgicos , Niño , Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Humanos , Federación de Rusia , Convulsiones , Resultado del Tratamiento
6.
Artículo en Ruso | MEDLINE | ID: mdl-32759925

RESUMEN

OBJECTIVE: To analyze the characteristics of paroxysmal syndrome in insular and temporal lobe tumors, to determine their relationship with the histological structure of tumor, to assess the effect of tumor growth nature on severity of disease. MATERIAL AND METHODS: A retrospective analysis enrolled 80 patients aged 11 - 80 years with insular and temporal lobe tumors and symptomatic epilepsy. All patients underwent surgery at the Polenov National Research Neurosurgery Center in Almazov National Medical Research Center for the period from 2012 to 2018. RESULTS: The main group consisted of 29 patients with tumors of temporal and insular lobes. Control group of 51 patients with temporal gliomas was formed for comparative analysis. It was found that involvement of insular lobe into paroxysmal syndrome is characterized by attacks with a motor component, somatosensory paroxysms, vegetative manifestations (respiratory attacks, salivation, nausea), speech disorders and taste hallucinations. Derealization, motor arrest and déjà vu/jamis vu paroxysms were more common in patients with temporal lobe lesion. Neoplastic lesion of the insular lobe shortens the period between manifestation of paroxysms and surgical treatment. Moreover, this type of disease is characterized by higher incidence of seizures compared to isolated temporal lobe tumors.


Asunto(s)
Epilepsia del Lóbulo Temporal/cirugía , Glioma , Neoplasias Supratentoriales , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Corteza Cerebral , Niño , Electroencefalografía , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estudios Retrospectivos , Lóbulo Temporal/diagnóstico por imagen , Adulto Joven
7.
Artículo en Ruso | MEDLINE | ID: mdl-30900691

RESUMEN

Epileptic seizures are some of the most frequent manifestations of cerebral AVMs in children. Poor control of seizures can significantly affect patients' quality of life. In this case, factors that are associated with the development of seizures and affect the efficacy of their control upon treatment of cerebral AVMs are not well understood. PURPOSE: The purpose of this study was to identify risk factors for the development of epileptic seizures as well as factors associated with a seizure-free outcome of AVM treatment in children. MATERIAL AND METHODS: We analyzed the results of examination and treatment in 89 patients with cerebral AVMs aged 1 to 17 years. RESULTS: Factors associated with the development of epileptic seizures in cerebral AVMs in children included male gender of the child, a large size of AVM and its superficial location, as well as localization of the pathology in the frontal and temporal lobes of the brain and draining varices. Regression of seizures after surgery was more often observed in the case of microsurgical and/or complex surgical treatment and complete exclusion of the AVM as well as in cases of rare attacks and a short course of the disease. CONCLUSION: Complex and microsurgical treatment of AVMs in children provides effective control of epileptic seizures, which is obviously associated with complete exclusion of the AVM and removal of the epileptic focus located near the AVM.


Asunto(s)
Malformaciones Arteriovenosas Intracraneales , Radiocirugia , Convulsiones , Adolescente , Niño , Preescolar , Humanos , Lactante , Masculino , Calidad de Vida , Factores de Riesgo , Resultado del Tratamiento
8.
Artículo en Ruso | MEDLINE | ID: mdl-29795084

RESUMEN

The use of catheterization cerebral angiography (CCA) to assess collateral blood flow through an indirect anastomosis is traumatic for children, uses a high radiation dose, and requires anesthetic care in most cases. AIM: we aimed to compare the capabilities of triplex ultrasound (TU) of vessels, magnetic resonance angiography (MRA), computed tomography angiography (CTA), and CCA in assessing the competence of indirect cerebral revascularization (ICR) in children. MATERIAL AND METHODS: ICR was performed in 18 children in 24 hemispheres (24 operations). The results were evaluated by Matsushima classification-based comparison of the data of preoperative and postoperative clinical examinations, TU of the superficial temporal artery, magnetic resonance imaging (MRI) and computed tomography (CT) of vessels, and selective cerebral angiography. RESULTS: After surgery, improvements in the neurological and neuropsychological status were assessed. Matsushima grade A collaterals were found in 12 (50%) cases, grade B collaterals were present in 3 (13%) cases, grade C collaterals were present in 7 (29%) cases, and grade D collaterals were detected in 1 (4%) case; in 1 (4%) case, the superficial temporal artery was not enhanced. MR angiography visualized 18 (75%) indirect anastomoses, CT angiography revealed 4 indirect anastomoses, and TU visualized 4 indirect anastomoses. Comparison of preoperative and postoperative TU data for the superficial temporal artery revealed significant changes in blood flow in the form of increased rate indices and a decreased resistance index; mean values of indices for each angiographic class of revascularization and significant differences in pre- and postoperative observations were calculated. CONCLUSION: Examination of ICR competence using CCA is necessary in the presence of persistent clinical signs of chronic cerebral circulatory insufficiency, absence of increased blood flow and decreased peripheral resistance in the superficial temporal artery, and lack of anastomosis according to MRA. The most optimal techniques for postoperative examination are MRA with perfusion and diffusion maps and TU.


Asunto(s)
Revascularización Cerebral , Enfermedad de Moyamoya , Anastomosis Quirúrgica , Angiografía Cerebral , Niño , Humanos , Angiografía por Resonancia Magnética
9.
Eur Phys J C Part Fields ; 77(5): 294, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28579921

RESUMEN

A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13[Formula: see text]. The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3[Formula: see text]. Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975[Formula: see text] are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400[Formula: see text] are excluded.

10.
Eur Phys J C Part Fields ; 77(4): 236, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28515665

RESUMEN

The WZ production cross section is measured by the CMS experiment at the CERN LHC in proton-proton collision data samples corresponding to integrated luminosities of 4.9[Formula: see text] collected at [Formula: see text], and 19.6[Formula: see text] at [Formula: see text]. The measurements are performed using the fully-leptonic WZ decay modes with electrons and muons in the final state. The measured cross sections for [Formula: see text] are [Formula: see text] [Formula: see text] and [Formula: see text] [Formula: see text]. Differential cross sections with respect to the [Formula: see text] boson [Formula: see text], the leading jet [Formula: see text], and the number of jets are obtained using the [Formula: see text] data. The results are consistent with standard model predictions and constraints on anomalous triple gauge couplings are obtained.

11.
Eur Phys J C Part Fields ; 77(4): 252, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28515669

RESUMEN

The nuclear modification factor [Formula: see text] and the azimuthal anisotropy coefficient [Formula: see text] of prompt and nonprompt (i.e. those from decays of b hadrons) [Formula: see text] mesons, measured from PbPb and pp collisions at [Formula: see text] [Formula: see text] at the LHC, are reported. The results are presented in several event centrality intervals and several kinematic regions, for transverse momenta [Formula: see text] [Formula: see text] and rapidity [Formula: see text], extending down to [Formula: see text] [Formula: see text] in the [Formula: see text] range. The [Formula: see text] of prompt [Formula: see text] is found to be nonzero, but with no strong dependence on centrality, rapidity, or [Formula: see text] over the full kinematic range studied. The measured [Formula: see text] of nonprompt [Formula: see text] is consistent with zero. The [Formula: see text] of prompt [Formula: see text] exhibits a suppression that increases from peripheral to central collisions but does not vary strongly as a function of either y or [Formula: see text] in the fiducial range. The nonprompt [Formula: see text] [Formula: see text] shows a suppression which becomes stronger as rapidity or [Formula: see text] increases. The [Formula: see text] and [Formula: see text] of open and hidden charm, and of open charm and beauty, are compared.

12.
Eur Phys J C Part Fields ; 77(3): 172, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28408859

RESUMEN

The cross section of top quark-antiquark pair production in proton-proton collisions at [Formula: see text] is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2[Formula: see text]. The measurement is performed by analyzing events in which the final state includes one electron, one muon, and two or more jets, at least one of which is identified as originating from hadronization of a b quark. The measured cross section is [Formula: see text], in agreement with the expectation from the standard model.

13.
Phys Rev Lett ; 118(12): 122301, 2017 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-28388204

RESUMEN

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p-Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range |η|<2.4, and a third particle measured in the hadron forward calorimeters (4.4<|η|<5). The observed differences between the same and opposite sign correlations, as functions of multiplicity and η gap between the two charged particles, are of similar magnitude in p-Pb and PbPb collisions at the same multiplicities. These results pose a challenge for the interpretation of charge-dependent azimuthal correlations in heavy ion collisions in terms of the chiral magnetic effect.

14.
Eur Phys J C Part Fields ; 77(1): 15, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28260978

RESUMEN

A measurement of the top quark pair production ([Formula: see text]) cross section in proton-proton collisions at the centre-of-mass energy of 8[Formula: see text] is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.6[Formula: see text]. This analysis is performed in the [Formula: see text] decay channels with one isolated, high transverse momentum electron or muon and at least four jets, at least one of which is required to be identified as originating from hadronization of a b quark. The calibration of the jet energy scale and the efficiency of b jet identification are determined from data. The measured [Formula: see text] cross section is [Formula: see text]. This measurement is compared with an analysis of 7[Formula: see text] data, corresponding to an integrated luminosity of 5.0[Formula: see text], to determine the ratio of 8[Formula: see text] to 7[Formula: see text] cross sections, which is found to be [Formula: see text]. The measurements are in agreement with QCD predictions up to next-to-next-to-leading order.

15.
Artículo en Ruso | MEDLINE | ID: mdl-28291213

RESUMEN

AIM: To analyze the efficacy and safety of 5-aminolevulinic acid for intraoperative fluorescence diagnosis (FD) during repeated surgery for recurrent neuroepithelial tumors (NETs) in children. MATERIAL AND METHODS: We performed a retrospective analysis of the results of recurrent NET resection in 13 children aged from 3 to 17 years in the period between December 2013 and May 2015. The source of 5-ALA was a drug "Alasens" that was administered at a dose of 20 mg/kg of body weight 4 h before the beginning of tumor resection. A visual scale was used to evaluate the fluorescence intensity. The drug was used with the informed consent of the child's parents and approval of the Polenov Neurosurgical Institute ethics committee. All patients underwent complex clinical and introscopic examination in the pre- and postoperative periods and a repeated histological tumor examination. RESULTS: There was no fluorescence in 4 cases (Gr I in 2 cases; Gr II in 2 cases). Grade 1 fluorescence (Gr II) was observed in one case, and grade 2-3 fluorescence was observed in the remaining 8 patients. Total and subtotal tumor resection was achieved in 11 (84.6%) of 13 patients. There were no clinically significant adverse effects. A transient increase in transaminases was observed in 2 patients. Two girls had an elevated photosensitivity to light for two days. CONCLUSION: FD is a safe technique in childhood and can improve intraoperative detection of NET during its repeated growth as well as differentiate the tumor from pathological tissues of non-tumorous nature, which increases completeness of blastomatous tissue removal. However, the character and intensity of fluorescence may change in recurrent NETs. Further research is required to investigate the FD effectiveness in various age patients with tumors of a different histological structure and malignancy in the case of both primary and recurrent lesions.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Neoplasias Encefálicas , Cuidados Intraoperatorios/métodos , Neoplasias Neuroepiteliales , Imagen Óptica/métodos , Adolescente , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Niño , Preescolar , Femenino , Humanos , Masculino , Neoplasias Neuroepiteliales/diagnóstico por imagen , Neoplasias Neuroepiteliales/cirugía
16.
Eur Phys J C Part Fields ; 77(2): 92, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28331430

RESUMEN

The production cross section of a W boson in association with two b jets is measured using a sample of proton-proton collisions at [Formula: see text] collected by the CMS experiment at the CERN LHC. The data sample corresponds to an integrated luminosity of 19.8[Formula: see text]. The W bosons are reconstructed via their leptonic decays, [Formula: see text], where [Formula: see text] or [Formula: see text]. The fiducial region studied contains exactly one lepton with transverse momentum [Formula: see text] and pseudorapidity [Formula: see text], with exactly two b jets with [Formula: see text] and [Formula: see text] and no other jets with [Formula: see text] and [Formula: see text]. The cross section is measured to be [Formula: see text]+[Formula: see text], in agreement with standard model predictions.

17.
Phys Rev Lett ; 118(2): 021802, 2017 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-28128610

RESUMEN

A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at sqrt[s]=8 TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5 fb^{-1}, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino.

18.
Eur Phys J C Part Fields ; 77(11): 751, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31999282

RESUMEN

Measurements of the associated production of a Z boson with at least one jet originating from a b quark in proton-proton collisions at s = 8 TeV are presented. Differential cross sections are measured with data collected by the CMS experiment corresponding to an integrated luminosity of 19.8 fb - 1 . Z bosons are reconstructed through their decays to electrons and muons. Cross sections are measured as a function of observables characterizing the kinematics of the b jet and the Z boson. Ratios of differential cross sections for the associated production with at least one b jet to the associated production with any jet are also presented. The production of a Z boson with at least two b jets is investigated, and differential cross sections are measured for the dijet system. Results are compared to theoretical predictions, testing two different flavour schemes for the choice of initial-state partons.

19.
Phys Rev Lett ; 117(5): 051802, 2016 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-27517765

RESUMEN

A search for the resonant production of high-mass photon pairs is presented. The analysis is based on samples of proton-proton collision data collected by the CMS experiment at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 3.3 fb^{-1}, respectively. The interpretation of the search results focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4 TeV and with widths, relative to the mass, between 1.4×10^{-4} and 5.6×10^{-2}. Limits are set on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. A modest excess of events compatible with a narrow resonance with a mass of about 750 GeV is observed. The local significance of the excess is approximately 3.4 standard deviations. The significance is reduced to 1.6 standard deviations once the effect of searching under multiple signal hypotheses is considered. More data are required to determine the origin of this excess.

20.
Artículo en Inglés | MEDLINE | ID: mdl-27471431

RESUMEN

The cross section for [Formula: see text] production in the all-jets final state is measured in pp collisions at a centre-of-mass energy of 8 [Formula: see text] at the LHC with the CMS detector, in data corresponding to an integrated luminosity of 18.4 [Formula: see text]. The inclusive cross section is found to be [Formula: see text] [Formula: see text]. The normalized differential cross sections are measured as a function of the top quark transverse momenta, [Formula: see text], and compared to predictions from quantum chromodynamics. The results are reported at detector, parton, and particle levels. In all cases, the measured top quark [Formula: see text] spectra are significantly softer than theoretical predictions.

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