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1.
Artículo en Ruso | MEDLINE | ID: mdl-38639150

RESUMEN

Within the framework of the «Health of Healthy¼ concept (A.N. Razumov) a medical, psychological and pedagogical «Sonatal-pedagogy¼ system (M.L. Lazarev) aimed at harmonizing the mental and physical development of children from the prenatal age has been developed In Russia. The system has been tested since 1983 on population of more than 70 thous. children. The results showed its high effectiveness and safety (in relation to pregnancy, childbirth, breastfeeding, somatic health, psychomotor development and children's abilities). Scaling of the Sonatal-pedagogy, in particular the system of prenatal education, will contribute to the sanitation of the Russian gene pool, demography improvement and formation of responsible parenthood.


Asunto(s)
Estado de Salud , Embarazo , Femenino , Humanos , Niño , Federación de Rusia
2.
J Environ Radioact ; 270: 107282, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37619406

RESUMEN

Fish in lakes situated within the Chornobyl exclusion zone have been highly contaminated since the accident and have not been utilized as food for humans. In the present study, field experiments with less-contaminated silver Prussian carp (Carassius gibelio (Bloch, 1782)) caged in contaminated lake within the Chornobyl exclusion zone was performed from June to October 2021 to investigate the effectiveness of clean feed containing potassium ferric hexacyanoferrate (KFCF) KFe[Fe(CN)6], a kind of Prussian Blue as a countermeasure to reduce 137Cs accumulation in fish. The addition of clean feed containing 0.1% or 1% KFCF resulted respectively in 2.4 ± 0.4 or 4.2 ± 0.7 times lower activity concentration of 137Cs in muscle tissue of the carp compared to control fish with clean feed without KFCF and in 7-16 or 12-27 times lower activities compared to fish without additional clean feeding. After 18 weeks exposure, 137Cs levels in all the caged fish except for the control group were below the European permissible level (600 Bq kg-1) for consumption. In contrast, KFCF did not affect the intake of 90Sr in fish, although additional feed increased the growth rate and thereby accumulation in bone tissues. Hence, the use of clean feed containing KFCF is judged to be an effective and inexpensive countermeasure to reduce the 137Cs contamination of edible fish muscles.


Asunto(s)
Accidente Nuclear de Chernóbil , Monitoreo de Radiación , Animales , Humanos , Lagos , Peces
3.
J Intern Med ; 283(6): 568-577, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29464806

RESUMEN

BACKGROUND: Use of the immune checkpoint inhibitor ipilimumab is sometimes complicated by ipilimumab-associated colitis (Ipi-AC), an immune-mediated colitis that mimics inflammatory bowel disease. OBJECTIVE: We sought to characterize the histopathologic and immunophenotypic features of Ipi-AC and to directly compare these features to ulcerative colitis (UC). METHODS: This is a retrospective cohort study of 22 patients with Ipi-AC, 12 patients with treatment-naïve UC and five controls with diarrhoea but normal endoscopic findings. Immunohistopathologic features were described, and quantitative immunohistochemistry (IHC) was performed for CD4, CD8, CD20, CD138 and FOXP3. RESULTS: Endoscopic findings in both the Ipi-AC and UC groups included ulcerated, oedematous and erythematous mucosa. Involvement of the GI tract was more diffuse in Ipi-AC. As compared to UC, a smaller proportion of Ipi-AC biopsies had basal plasmacytosis (14% for Ipi-AC vs. 92% for UC, P < 0.0001) and crypt distortion (23% for Ipi-AC vs. 75% for UC, P = 0.003), whereas Ipi-AC biopsies had more apoptotic bodies in the left colon (17.6 ± 15.3 for Ipi-AC vs. 8.2 ± 4.2 for UC, P = 0.011). Cryptitis, ulcerations and crypt abscesses were common in both groups. Biopsy specimens from Ipi-AC had a lower density of CD20-positive lymphocytes than UC (275.8 ± 253.3 cells mm-2 for Ipi-AC vs. 1173.3 ± 1158.2 cells mm-2 for UC, P = 0.022) but had a similar density of CD4, CD8, CD138 and FOXP3-positive cells. CONCLUSIONS: Ipi-AC is a distinct pathologic entity with notable clinical and histopathological differences compared to UC. These findings provide insights into the pathophysiology of immune-related adverse events (iAEs) from ipilimumab therapy.


Asunto(s)
Antineoplásicos Inmunológicos/efectos adversos , Colitis/inducido químicamente , Ipilimumab/efectos adversos , Adulto , Colitis/inmunología , Colitis/patología , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Diarrea/etiología , Femenino , Humanos , Inmunohistoquímica , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Estudios Retrospectivos
4.
Sci Rep ; 4: 3742, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24434734

RESUMEN

The structure of the [001]-oriented single crystalline tungsten probes sharpened in ultra-high vacuum using electron beam heating and ion sputtering has been studied using scanning and transmission electron microscopy. The electron microscopy data prove reproducible fabrication of the single-apex tips with nanoscale pyramids grained by the {011} planes at the apexes. These sharp, [001]-oriented tungsten tips have been successfully utilized in high resolution scanning tunneling microscopy imaging of HOPG(0001), SiC(001) and graphene/SiC(001) surfaces. The electron microscopy characterization performed before and after the high resolution STM experiments provides direct correlation between the tip structure and picoscale spatial resolution achieved in the experiments.

5.
Phys Rev Lett ; 101(7): 076602, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18764562

RESUMEN

We report a surprisingly long spin relaxation time of electrons in Mn-doped p-GaAs. The spin relaxation time scales with the optical pumping and increases from 12 ns in the dark to 160 ns upon saturation. This behavior is associated with the difference in spin relaxation rates of electrons precessing in the fluctuating fields of ionized or neutral Mn acceptors, respectively. For the latter, the antiferromagnetic exchange interaction between a Mn ion and a bound hole results in a partial compensation of these fluctuating fields, leading to the enhanced spin memory.

6.
Phys Rev Lett ; 93(21): 216402, 2004 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-15601037

RESUMEN

We report a large and unexpected suppression of the free electron spin-relaxation in lightly doped n-GaAs bulk crystals. The spin-relaxation rate shows a weak mobility dependence and saturates at a level 30 times less than that predicted by the Dyakonov-Perel theory. The dynamics of the spin-orbit field differs substantially from the usual scheme: although all the experimental data can be self-consistently interpreted as a precessional spin-relaxation induced by a random spin-orbit field, the correlation time of this random field, surprisingly, is much shorter than, and is independent of, the momentum relaxation time determined from transport measurements.

7.
Neuroimage ; 11(6 Pt 1): 624-33, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10860791

RESUMEN

Evidence of bilateral prefrontal activation during memory encoding and retrieval has increased attention given to anatomical subdivisions within the prefrontal cortex. The current study examined anterior and inferior aspects of the prefrontal cortex to determine their degree of functional and hemispheric overlap during encoding and recognition. Cerebral blood flow of 25 healthy volunteers was measured using PET (15)O-water methods during four conditions: resting baseline, sequential finger movement, word encoding, and word recognition. Resting and motor images were averaged to provide a single reference that was subtracted from encoding and recognition using statistical parametric mapping (SPM96). Memory conditions were also subtracted from each other to identify differences in regional activity. Subjects performed well (86% correct) and had a slightly conservative response bias. Baseline subtraction from encoding revealed focal activation of left inferior prefrontal cortex (area 45) without significant contralateral activation. Recognition minus baseline subtraction produced a focal right anterior prefrontal activation (areas 9 and 10) that was not present in the left hemisphere. Bilateral effects were seen in area 45 during recognition. Subtraction of memory tasks from each other did not reveal any areas of greater activity during encoding. However, the recognition task produced greater activation in right area 9 extending into the anterior cingulate. Greater activity during recognition was also observed in left insula and bilateral visual integration areas. These results are discussed in relation to the prevailing model of prefrontal hemispheric asymmetry during episodic memory.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Reconocimiento Visual de Modelos/fisiología , Corteza Prefrontal/fisiología , Lectura , Tomografía Computarizada de Emisión , Adulto , Circulación Cerebrovascular/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Corteza Prefrontal/diagnóstico por imagen , Valores de Referencia , Técnica de Sustracción , Conducta Verbal/fisiología
8.
Artículo en Inglés | MEDLINE | ID: mdl-10645739

RESUMEN

OBJECTIVE: We postulated that disruption of callosal pathways as occurs in Marchiafava-Bignami disease (MBD) is associated with marked impairment in brain functioning as measured by cognitive assessment and neuroimaging. BACKGROUND: MBD is considered to be a rare and severe complication of chronic alcoholism. It is characterized by necrosis and subsequent atrophy of the corpus callosum, which is the major brain structure connecting corresponding areas of both hemispheres. METHODS: We review the existing literature on MBD with respect to conceptualization, theories of pathogenesis, forms of the disease, and neuroimaging and neuropsychological findings. We then present the case of a middle-aged man with MBD who underwent extensive clinical, neuropsychological, and neuroimaging studies. RESULTS: Neuropsychological evaluation revealed a pattern of severe global dementia. Magnetic resonance imaging showed moderate atrophy of anterior callosal regions and severe atrophy of posterior callosal regions in the setting of cortical and subcortical atrophy. Resting metabolism positron emission tomography revealed decreased glucose metabolism most pronounced in subcortical and mesial frontal regions. The differential diagnosis, function of the corpus callosum, and potential limitations of our case study are discussed. CONCLUSIONS: On account of the history, clinical presentation, and results of magnetic resonance imaging of the brain, we diagnosed our patient with chronic MBD.


Asunto(s)
Trastornos Relacionados con Alcohol/fisiopatología , Cuerpo Calloso/efectos de los fármacos , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Tomografía Computarizada de Emisión , Trastornos Relacionados con Alcohol/diagnóstico , Atrofia , Cuerpo Calloso/patología , Cuerpo Calloso/fisiopatología , Etanol/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Síndrome
9.
Neuropsychology ; 12(3): 399-413, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9673996

RESUMEN

Schizophrenia affects prefrontal and temporal-limbic networks. These regions were examined by contrasting regional cerebral blood flow (rCBF) during executive (Wisconsin Card Sorting Test [WCST]), and declarative memory tasks (Paired Associate Recognition Test [PART]). The tasks, and a resting baseline, were administered to 15 patients with schizophrenia and 15 healthy controls during 10 min positron emission tomography 15O-water measures of rCBF. Patients were worse on both tasks. Controls activated inferior frontal, occipitotemporal, and temporal pole regions for both tasks. Similar results were obtained for controls matched to level of patient performance. Patients showed no activation of hypothesized regions during the WCST and activated the dorsolateral prefrontal cortex during the PART. On the PART, occipitotemporal activation correlated with better performance for controls only. Better WCST performance correlated with CBF increase in prefrontal regions for controls and in the parahippocampal gyrus for patients. Results suggest that schizophrenia may involve a breakdown in the integration of a frontotemporal network that is responsive to executive and declarative memory demands in healthy individuals.


Asunto(s)
Circulación Cerebrovascular/fisiología , Trastornos del Conocimiento/fisiopatología , Lóbulo Frontal/fisiopatología , Trastornos de la Memoria/fisiopatología , Esquizofrenia/fisiopatología , Lóbulo Temporal/fisiopatología , Adulto , Análisis de Varianza , Atención/fisiología , Mapeo Encefálico , Estudios de Casos y Controles , Trastornos del Conocimiento/diagnóstico por imagen , Formación de Concepto/fisiología , Femenino , Lóbulo Frontal/irrigación sanguínea , Lóbulo Frontal/diagnóstico por imagen , Humanos , Inhibición Psicológica , Sistema Límbico/irrigación sanguínea , Sistema Límbico/diagnóstico por imagen , Sistema Límbico/fisiopatología , Modelos Lineales , Masculino , Memoria/fisiología , Trastornos de la Memoria/diagnóstico por imagen , Memoria a Corto Plazo/fisiología , Pruebas Neuropsicológicas , Esquizofrenia/diagnóstico por imagen , Psicología del Esquizofrénico , Lóbulo Temporal/irrigación sanguínea , Lóbulo Temporal/diagnóstico por imagen , Tomografía Computarizada de Emisión , Aprendizaje Verbal/fisiología , Volición/fisiología
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