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Acoustic properties of buried graphitized layers in diamond formed by ion implantation followed by annealing were studied using the picosecond ultrasonic technique with spatial resolution. Two methods of elastic pulse generation were used: heating an aluminum film deposited on a diamond sample by femtosecond laser pulses and direct illumination of the graphitized layers by these pulses. We applied a multilayered model of the acousto-optical response to fit experimental results and estimate the distribution of the acoustical parameters (wave resistance, viscoelastic damping, and longitudinal sound speed) of the structures under study in depth. It was found that unique sets of spectral lines are present in the Fourier spectra of measured responses in regions with different internal structures. Mapping of the Fourier spectra made it possible to visualize regions with different internal structures. The combined use of depth profiling and mapping can serve as a tool for hypersound tomography.
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A piezoelectric force sensor is suggested for magnetic force microscopy (MFM) purposes. Added between the piezoelectric resonator and the magnetic probe is a mechanical force amplifier in the form of a thin, long resonant arm with an integral micro-rod whereby the amplitude of the force acting on the probe is amplified by a factor of 20 to 40 at a low noise level. When the sensor was operated in air, its noise floor was found to be 1.4 pN (RMS) at a bandwidth of 100 Hz. The piezoelectric sensor requires no repeated calibration; and it is capable of operating in a vacuum, and at cryogenic temperatures. By using this sensor we carried out the MFM of ultrathin (1.5- and 3-nm-thick) Ni79Fe21 permalloy films. The 1.5-nm-thick permalloy films studied have a nanoisland structure, whereas 3-nm-thick ones are contiouous. Domain structures were found in both. The MFM image was found to suffer substantial changes when the external magnetic field was altered by 1 Oe. The structures under study featured both "elastic" and "viscous" magnetic force components.
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AIM: To analyze clinical and genetic characteristics of PCDH19-associated epilepsy in a sample of patients from the Russian population. MATERIAL AND METHODS: The sample of patients with early epileptic encephalopathies included 16 people aged 10 month to 30 years. All patients underwent neurological examination according to standard methods, exome sequencing and EEG monitoring. RESULTS: Most of the identified mutations led to a shift in the reading frame or the formation of a termination codon. Six of them were duplications, four were deletions of one nucleotide, and three were nonsense mutations. Consistent with earlier studies, the authors identified the polymorphism of clinical manifestations of seizures that did not depend on the type of mutation and its localization. CONCLUSION: Based on the study of the clinical and genetic characteristics of the patients, the authors conclude that the so-called 'hot spots' are present in the PCDH19 gene, which are more common in the group of patients with mutations in this gene, and that the clinical picture of early infantile epileptic encephalopathy type 9 is variable.
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Cadherinas/genética , Epilepsia/genética , Epilepsia/fisiopatología , Mutación , Adolescente , Adulto , Niño , Preescolar , Bases de Datos Genéticas , Humanos , Lactante , Protocadherinas , Federación de Rusia , Adulto JovenRESUMEN
The impact of such factors as the shape of the applied voltage pulse, the friction force, and the mass of the movable part on the motor operation at low temperatures is experimentally investigated. Important added features in the motor design are support springs. These springs prevent one part of the slider clamp from shifting relative to the other during motion. The optimization of the factors listed above provided for reliable withdrawal of the microscope's fiber probe with a speed of up to 0.2 µm/step at a temperature of 5 K.
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PURPOSE: Developmental and epileptic encephalopathies (DEEs) are severe clinical conditions characterized by stagnation or decline of cognitive and behavioral abilities preceded, accompanied or followed by seizures. Because DEEs are clinically and genetically heterogeneous, next-generation sequencing, especially exome sequencing (ES), is becoming a first-tier strategy to identify the molecular etiologies of these disorders. METHODS: We combined ES analysis and international data sharing. RESULTS: We identified 11 unrelated individuals with DEE and de novo heterozygous truncating variants in the interferon regulatory factor 2-binding protein-like gene (IRF2BPL). The 11 individuals allowed for delineation of a consistent neurodevelopmental disorder characterized by mostly normal initial psychomotor development followed by severe global neurological regression and epilepsy with nonspecific electroencephalogram (EEG) abnormalities and variable central nervous system (CNS) anomalies. IRF2BPL, also known as enhanced at puberty protein 1 (EAP1), encodes a transcriptional regulator containing a C-terminal RING-finger domain common to E3 ubiquitin ligases. This domain is required for its repressive and transactivating transcriptional properties. The variants identified are expected to encode a protein lacking the C-terminal RING-finger domain. CONCLUSIONS: These data support the causative role of truncating IRF2BPL variants in pediatric neurodegeneration and expand the spectrum of transcriptional regulators identified as molecular factors implicated in genetic developmental and epileptic encephalopathies.
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Proteínas Portadoras/genética , Epilepsia/genética , Trastornos del Neurodesarrollo/genética , Proteínas Nucleares/genética , Convulsiones/genética , Adolescente , Adulto , Sistema Nervioso Central/diagnóstico por imagen , Sistema Nervioso Central/patología , Niño , Electroencefalografía , Epilepsia/diagnóstico por imagen , Epilepsia/fisiopatología , Femenino , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación , Trastornos del Neurodesarrollo/diagnóstico por imagen , Trastornos del Neurodesarrollo/fisiopatología , Fenotipo , Convulsiones/diagnóstico por imagen , Convulsiones/fisiopatología , Secuenciación del Exoma , Adulto JovenRESUMEN
Genetic epileptic encephalopathies are a rather wide spectrum of childhood epilepsies with onset of epilepsy in the first 1.5-2 years of life, regression or delayed psychomotor and speech development and 'massive' epileptiform activity on electroencephalogram (EEG). The review discusses the difficulties of choosing the optimal method of genetic examination, problems with the interpretation of the results obtained, the formulation of the diagnosis, the determination of the prognosis of the course and targeted therapy. It is emphasized that the interpretation of the identified genetic variants is not an easy task, requiring close interaction between specialists in molecular genetics, bioinformatics, neurology and clinical genetics. The possibilities of targeted treatment of genetic epileptic encephalopathies are still limited, but knowledge of the genetic cause of epilepsy allows making a more informed choice of the treatment.
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Epilepsia Generalizada/diagnóstico , Epilepsia Generalizada/terapia , Pruebas Genéticas , Neurólogos , Epilepsia Generalizada/genética , Humanos , PronósticoRESUMEN
This review presents the recently published revised classifications of epilepsies and seizure types developed by the International League Against Epilepsy (ILAE). The Classification of Epilepsies includes several diagnostic levels (steps): 1) from seizure type to epilepsy type (generalized/focal/combined generalized and focal/unknown), 2) diagnosis of epilepsy syndrome 3) etiology (genetic/ structural/ infectious/ metabolic/ immune/unknown). A clinician can use any level of the classification. Operational classification of seizure types is replaced by the previous classification that was grounded on the anatomical basis. Seizures are classified by the onset (focal, generalized or unknown). All types of seizures can be motor or non-motor. Focal seizure may evolve to bilateral tonic-clonic (previously called secondary-generalized). Atonic, clonic, tonic, myoclonic seizures and epileptic spasms can be either of focal or generalized onset. Unclassified type of seizure was introduced. New types of seizures (absence with eyelid myoclonia, myoclonic absence, myoclonic atonic and clonic-tonic-clonic seizures) were added. New terminology, definitions and some concepts developed by ILAE are presented.
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Actitud del Personal de Salud , Psiquiatría/tendencias , Predicción , HumanosRESUMEN
Epileptic encephalopathies (EE) are the group of progressive conditions with various etiologies that can produce neurocognitive deficit both per se and due to constant epileptiform discharges. Epileptic encephalopathies constitute about 15% of epilepsy in childhood and 40% of all seizures occurring in the first 3 years of life. Ten syndrome forms of EE are identified. Genetic factors contribute to 70-80% of all epileptic diseases and approximately 40% of idiopathic epilepsies have a monogenic mode of inheritance. Thirty-five genes of EE have been identified and the search is still continuing. The marked genetic heterogeneity of early EE, including 16 with autosomal-dominant-, 13 with autosomal-recessive-, 4 with X-linked recessive- and 2 with X-linked autosomal inheritance, was shown. The article describes differentiated approaches to the treatment of certain EE syndromes. Recent publications record the effectiveness of targeted therapy for certain forms of monogenic early EE (stiripentol in SCN1A mutations, diphenine in SCN8A mutations, levetiracetam in STXBP1 mutations). These results indicate the necessity for accurate diagnosis of genetic variants in early infantile EE for preventive actions in burdened families and for increasing the effectiveness of treatment.
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Mutación , Espasmos Infantiles/genética , Predisposición Genética a la Enfermedad , Humanos , Espasmos Infantiles/terapiaAsunto(s)
Maxilar/lesiones , Traumatismos del Cuello/etiología , Senos Paranasales/lesiones , Heridas por Arma de Fuego/complicaciones , Adolescente , Humanos , Masculino , Maxilar/cirugía , Traumatismo Múltiple , Traumatismos del Cuello/cirugía , Senos Paranasales/cirugía , Heridas y Lesiones/etiología , Heridas y Lesiones/cirugía , Heridas por Arma de Fuego/cirugíaRESUMEN
Season of activity of Aedes pullatus Coq. mosquitos in the Khibini mountains (the Murmansk region) was divided into 5 periods basing on their behaviour as well as on ecological and physiological pecularities. Seasonal activity periods for different years vary from the 1-2nd decade of July to the 2-3rd decade of September.
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Aedes , Animales , Estaciones del Año , U.R.S.S.Asunto(s)
Culicidae/fisiología , Animales , Culicidae/clasificación , Ecología , Densidad de Población , Federación de RusiaAsunto(s)
Cloroplastos/metabolismo , Fotosíntesis , Citocromos/análisis , Cinética , Plantas , Espectrofotometría , Factores de TiempoRESUMEN
According to its orographic characteristics and climate the Murmansk region represents a special landscape area of the Atlantic-Arctic zone with its peculiar zoogeographic characters. This specificity is clearly seen in the distribution of 19 species of bloodsucking mosquitoes over the above territory. Abundant and widely encountered are only two species, Aedes punctor and Ae. communis. 9 species, Culiseta alaskaensis, C. bergrothi, Aedes pullatus, Ae. excrucians, Ae. pionips, Ae. hexodontus, Ae. impiger, Ae. nigripes, Ae. diantaeus, are small in number and widely distributed. 8 species, Anopheles maculipennis, Aedes intrudens, Ae. cantans, Ae. cinereus, Ae. cataphylla, Ae. riparins, Ae. lencomelas, Culex pipiens pipiens, are rare and have a restricted distribution.