RESUMO
The aim of this work was to examine the content of thioredoxin in fibroblasts of human dermis from the development until deep aging (from 20 weeks of pregnancy until 85 years old), and defining of a role of thioredoxin in age-dependent changes in the number of fibroblasts in the dermis. Thioredoxin, proliferating cells nuclear antigen (PCNA), marker of fibroblasts vimentin were detected with indirect immunohistochemical technique. Results showed that portion of fibroblasts with positive staining for thioredoxin in the dermis is increased from 20 weeks of pregnancy until 85 years old. Most expressed age related increase in portion of thioredoxin positive dermal fibroblasts (more than 9 times) is present form birth until 20 years as compared to antenatal period. General number and percent of PCNA positive fibroblasts in dermis are decreased with age with more expressed changes until 40 years old. Correlation analysis showed that age dependent decrease in the number of fibroblasts and their proliferative activity is significantly associated with increase in thioredoxin positive fibroblasts in dermis. Results allow to suggest that thioredoxin play a role in age dependent decrease in the number of fibroblasts and their proliferation in human dermis.
Assuntos
Derme , Fibroblastos , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Humanos , Gravidez , Antígeno Nuclear de Célula em Proliferação , Tiorredoxinas , VimentinaRESUMO
EEG power changes in anaesthetized and conscious rats were studied (under repeated experiments) in wide frequency band (0.1-200 Hz) during cortical spreading depression wave (SD). In anaesthetized rats the decrease of EEG spectral power was shown through all diapasons under consideration. The most pronounced decay of the EEG power was marked in the 30-40 Hz band (27.3 ± 18.5, p = 2.46 x 10-(11)). In other frequency ranges the power decrease was less but its significance remained high. In conscious rats the simultaneous decay of the EEG power from 20 to 100 Hz range was also the most informative index of SD wave. The maximum power loss was found for band 30-40 Hz (11.2 ± 7.8, p = 2.55 x 10(-7)). It was shown that besides of EEG power decay the development of SD wave was characterized by the appearance of high frequency activity in front of SD and at the end of it. The increase of high-frequency activity in front of SD wave appeared in the ipsilateral hemisphere and moved along the cortex with the velocity of the SD wave itself. However the bursts of high frequency activity at the end of unilateral SD occurred simultaneously in both hemispheres and lasted 1.5-2.5 min. Findings contribute to detection of SD wave on basis of EEG spectral analysis.
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Córtex Cerebral/fisiologia , Estado de Consciência/fisiologia , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Vigília/fisiologia , Anestésicos Intravenosos , Animais , Eletrodos Implantados , Eletroencefalografia , Ratos , Técnicas Estereotáxicas , TiopentalRESUMO
The author's exam diagnostic features standard X-ray im- aging, X-ray computed tomography and bronchoscopy of lung cancer diagnosis on basis of tests diagnostic information value (accuracy, sensitivity and specificity).
Assuntos
Broncoscopia , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The dominant centre is a zone of proof higher excitation of neurons in the cortex of the brain, resulting from long stimulation or effector (in our case of a forepaw of an animal) or direct cortical representations of this effector. Besides of higher excitation and the firmness of excitation neurones, the dominant centre has two more very important properties--ability to summation (addition) coming to a cortex and extending on cortical neural networks excitations and inertia. Last property is shown what even in some days after the termination of the stimulations which have formed a dominant, in reply to testing stimulus (earlier indifferent for an animal) the centre is activated and puts in action effector. By means of irritation of a paw of rabbits rhythmic impulses of a current of threshold force us had been formed a rhythmic defensive dominant. Interconnected (coincidence) neuronal activity of the sensorimotor cortex of rabbits, in which the rhythmic defensive dominanta has been created, was investigated. Temporal of sequences intervals between the coincidence impulses in peaks of crosscorrelation histograms (CCH) was analyzed. Frequency of occurrence of the coincidence impulses (intervals between impulses), forming CCH was defined by means of "secondary" autocorrelation histograms (ACH) in during a minute. Peaks on "secondary" ACH showed prevalent intervals between of the coincidence impulses. For the further analysis only those peaks of "secondary" ACH, which prevailed over an average level of the histogram with significance p < 0.05 was used. It has been found that in the formed locus of the defensive dominant the coincidence impulses appear not only in the rhythm of stimulation applied in experiment-- s, but also in multiple beat to it (4, 6 and 8 s). Registration and analysis of neuronal activity were done after creation of a rhythmic dominant. At the beginning of each experiment (i.e. before a presentation of testing stimulus) single 2 --econd peaks were mainly observed, but doubles peaks of coincidence im-ulses appeared with latency 2, 4 or 6 s, were absent or appeared a few case. During application of testing stimulus a significant increase doubles peaks was observed. It is supposed, that application of testing stimulus strengthens already created earlier latent focus of excitation, which begin proved as a compli-ation of rhythm:.
Assuntos
Condicionamento Psicológico/fisiologia , Potenciais Evocados Auditivos/fisiologia , Córtex Sensório-Motor/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , Estimulação Elétrica , Membro Anterior , Rede Nervosa , Periodicidade , CoelhosRESUMO
In the course of analysis of the conjugate unit activity of simultaneously recorded neurons in the sensorimotor cortex of rabbits, 22 closed neural circuits consisting of 3 or 4 neurons were considered. In the model of the defensive dominanta, 1-3 weeks after imposing rhythmic (2 s) activity to a rabbit, the distribution of coincident impulses was analyzed in real time. It was found out that the events when the coincident impulses of neural pairs were generated with two-second intervals could be shifted in time and space over a closed circuit of neurons in one direction. Two-second intervals between the coincident impulses of the neighboring pairs could be conjugate, i.e. the end of one interval in one pair coincided with the beginning of a two-second interval in the next pair. Conjugate intervals of the neighboring neural pairs could promote a pass-through of the information on the stimulus properties over the closed neuronal circuit, thus completing a full cycle. The longest passes-through lasted from 10 and 12 s. Also, more intricate variants of the information transfer were revealed. Thus, not only passes-through of the two- second intervals between the neuronal pairs were observed, but also, coincident impulses repeatedly occurred with this interval in some of the pairs of the circuits. The longest transitions lasted 16 and 22 s.
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Córtex Auditivo/fisiologia , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Eletrodos , Potenciais Evocados/fisiologia , Atividade Nervosa Superior/fisiologia , Masculino , Neurônios/fisiologia , Estimulação Física/métodos , Coelhos , Fatores de TempoRESUMO
Quantitative determination of the molecular orientation distribution function in samples of liquid crystals with a complex director geometry was performed using the numerical simulation of electron paramagnetic resonance (EPR) spectra of the spin probes in a liquid-crystalline medium. To achieve the quantitative agreement of experimental and simulated EPR spectra, the hierarchy of the orientation order was explicitly taken into account, namely, the local ordering of liquid crystal molecules by the mean-field potential of surrounding molecules, and the partial disordering of local directors within the sample. The samples under study are planar and twist LC cells with liquid crystal 8CB cooled from the nematic into the smectic A phase in the magnetic field. The presence of the magnetic field perpendicular to the cell director leads to distortion of the orientation of the liquid crystal in the cell. The spin probe technique was successfully employed for the reliable measurement of orientation distribution functions of the low nonorthorhombic symmetry. Orientation order parameters up to 12th rank were measured, including nonaxial and nonorthorhombic order parameters. It is shown that the presence of several contradicting aligning forces leads to the tilt of the preferential director toward the direction, which is a compromise between the orienting forces.
Assuntos
Cristais Líquidos , Simulação por Computador , Espectroscopia de Ressonância de Spin Eletrônica , Cristais Líquidos/química , Transição de FaseRESUMO
This review summarizes the results of the study of the provisionality phenomenon in the development of the organs of the urinary system (mesonephros, metanephros) in viviparous (human, rat) and oviparous (bird) amniotes, human organs of mixed origin (pituitary, ovary, stomodeum) reparative regeneration of supporting tissues (in humans and Syrian hamster), morphogenesis of primary hepatic cancer developing against the background of superinvasive opisthorchiasis. It is shown that during the development of tissues and organs, the stages of provisional and definitive histo- and organogenesis could be determined; saltatory mechanism is typical for embryonic organogenesis (formation of cartilaginous skeletal primordia, meso- and metanephrons) and foci of oncogenesis. Transformation zones of the type of tissue organization in the epithelium are located in the areas of contacts of the derivatives of different embryonic primordia. Mechanism of transformation of the epithelial layer of stomodeum and Rathke's pouch is provided by local activation of apoptosis and by the formation of the epithelial cells of a qualitatively new generation.
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Organogênese , Animais , Aves , Transformação Celular Neoplásica/patologia , Cricetinae , Epitélio/embriologia , Trato Gastrointestinal/embriologia , Humanos , Fígado/embriologia , Neoplasias Hepáticas/patologia , Mesocricetus , Hipófise/embriologia , Ratos , Sistema Urinário/embriologiaRESUMO
Coincident activity of pairs of neurons in the sensorimotor and visual areas of the cerebral cortex was studied in naive, learning, and trained rabbits during the formation of a hidden excitation focus in their central nervous system (a defensive dominanta) of the rhythmic nature. In the trained rabbits (as compared to the naive animals), percent of neuronal pairs (both neighboring and distant) in whose coincident activity the rhythm of stimulation prevailed was higher. In the visual cortex, percent of such pairs was significantly higher only for the distant neurons. Analysis of interaction between neurons in the visual and sensorimotor cortices revealed increasing the number of neuronal pairs with the driven rhythm while training. Such an increase was observed when both sensorimotor and visual neurons were considered as leading.
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Córtex Motor/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Córtex Visual/fisiologia , Animais , Masculino , Córtex Motor/citologia , Coelhos , Córtex Visual/citologiaRESUMO
Defensive dominanta was formed in rabbit CNS. Activity of the cortical neuronal network was investigated in these rabbits in the state of quiet wakefulness and in the intervals between the presentations of testing stimulus (light flashes). Statistical analysis of spike trains revealed some distinctions in neuronal functional organizations in the excitation focus (sensorimotor cortex) and in the visual cortex in the states of quiet wakefulness, before the movement of the paw, and before the omission of the reaction. The evidence of different roles in the network activity of sensorimotor neurons that responded and not responded to light was obtained.
Assuntos
Mecanismos de Defesa , Dominância Cerebral , Neocórtex/fisiologia , Córtex Somatossensorial/fisiologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Neurônios/fisiologia , Coelhos , VigíliaRESUMO
The interaction between neurons of sensorimotor and visual cortices was investigated by cross-correlation analysis. In this interaction, we examined the role of sensorimotor neurons responding to light. In rabbits with a hidden focus of excitation, neurons of the sensorimotor cortex responding to light significantly more often formed correlation joints with cells of the visual cortex than neurons not responding to light. On the other hand, neurons of the visual cortex significantly more often formed correlation joints with neurons of the sensorimotor cortex not responding to light.
Assuntos
Membro Anterior/fisiologia , Córtex Motor/fisiologia , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Córtex Visual/fisiologia , Animais , Estimulação Elétrica , Rede Nervosa/fisiologia , Estimulação Luminosa , CoelhosRESUMO
The latent excitation focus in the sensorimotor cortex of rabbits was formed by a series of pulses of the threshold current applied on a paw with 2-second intervals. After repeated applications of the routine immobilization procedure, besides the 2-second starts of the paw in response to testing stimulus, spontaneous starts appeared with the intervals close to 3 and 4 seconds. The analysis of the coincident (interconnected) activity of pairs of nearby neurons in the sensorimotor cortex of three rabbits repeatedly exposed to the immobilization procedure showed that (a) in situations when animals made movements with the intervals of 2 seconds, the 2-second rhythm prevailed in the coincident activity of neurons; (b) during movements made with the 3-second interval, a 3-second rhythm was more frequently revealed in the coincident activity of cells, (c) in the situations when the animals did not make movements, either 2-, or 3-second rhythms were equiprobably observed in the connected activity of nearby neurons. In all these three situations, the 2-second rhythm prevailed in the connected activity of distant neurons, i.e., the rhythm which was imposed to animals during formation of the latent center of excitation.
Assuntos
Atividade Motora , Córtex Motor/fisiologia , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Estimulação Elétrica , Resposta de Imobilidade Tônica , Periodicidade , Coelhos , Tempo de ReaçãoRESUMO
Temperature dependences of electron paramagnetic resonance (EPR) spectra of an imidazoline nitroxide biradical spin probe in a series of room-temperature ionic liquids in the temperature range 124-390 K have been quantitatively simulated. The unusual asymmetric EPR spectrum shape previously observed in these systems [Kokorin et al., Appl. Magn. Res. 48 (2016) 287] is shown to originate from anisotropic rotational diffusion of the probe molecule. All experimental spectra were quantitatively reproduced in simulation using a unified set of geometrical and magnetic parameters of the spin probe, which were found to be fully consistent with the biradical geometry obtained from density functional theory calculations. Temperature dependences of rotation diffusion coefficient of the probe characterize the molecular mobility of the ionic liquid, whereas the temperature dependences of the spin-exchange integral J and of the isotropic hyperfine interaction constant, aN, are shown to reflect the intramolecular conformation motions of the biradical probe.
RESUMO
A hidden excitation focus of the rhythmic nature (a rhythmic defensive dominant focus) was produced in the rabbit's CNS. The focus was formed by means of threshold electrodermal stimulation of the left forelimb by series of pulses consisting of 15-20 stimuli with 2 s intervals between the pulses. Correlated activity of cells in the sensorimotor cortex of the right and left brain hemispheres was analyzed. In cases when crosscorrelation histograms were constructed by the results of the analysis of discharges of the left-side cortical of neurons regarding high- and middle-amplitude pulses in a right hemisphere, 15 and 23 % of correlated neural pairs, respectively, revealed the prevalence of the rhythm identical or close to the initial rhythm of stimulation that formed the hidden excitation focus. In contrast, in cases when the same analysis was applied to the right-side cortical neurons regarding high- and middle-amplitude discharges in the left hemisphere, prevalence of the dominant 2-second rhythm was revealed in correlated activity of only 3 and 10% of neural pairs, respectively. After the exposure to "animal hypnosis" procedure, the distinctions between the brain in this parameter were eliminated.
Assuntos
Cérebro/fisiologia , Lateralidade Funcional/fisiologia , Resposta de Imobilidade Tônica/fisiologia , Córtex Motor/fisiologia , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Potenciais de Ação , Animais , Estimulação Elétrica , Periodicidade , CoelhosRESUMO
The article includes experience with treatment of 103 patients with the formed different large intestine anastomoses. Primary operations for cancer of the rectum were made on 76 patients, restorative operations--on 27 patients. The following techniques were used: manual formation of the large intestine anastomosis, apparatus anastomoses using AKA-2, "ETHICON CDH" and double apparatuses method using "CONTOUR" and "ETHICON CDH". It was found that the application of stitching apparatuses required shorter time necessary for applying large intestine anastomosis and for operation. When forming the large intestine anastomoses in the abdominal cavity the manual method should be preferred. The formation of anastomosis in the small pelvis cavity is accompanied by technical problems and requires using stitching apparatuses. The method using apparatuses "CONTOUR" and "ETHICON CDH" decreases the number of postoperative complications and can extend the list of indications for performing sphincter-sparing operations.
Assuntos
Competência Clínica/normas , Colectomia/métodos , Colo/cirurgia , Guias de Prática Clínica como Assunto , Neoplasias Retais/cirurgia , Reto/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/métodos , Colonoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Estudos Retrospectivos , Técnicas de Sutura/instrumentação , Resultado do TratamentoRESUMO
A model-free approach for simulation of EPR spectra of nitroxide spin probes in liquid-crystalline materials was suggested and used to obtain parameters of molecular orientation and rotational mobility. The developed method is based on experimental recording and numerical simulation of the angular dependence of EPR spectra, which is shown to be much more informative in comparison with a single EPR spectrum. Quantitative spectral simulations considering both local orientational ordering and distribution of local directors in the sample were used for discrimination of models of rotational mobility and orientational alignment. The method was applied for detailed quantitative characterization of axial, orthorhombic, and low-symmetry non-orthorhombic molecular orientation distributions. It is shown that the ordinarily used model of rotational diffusion in a mean-field potential is suitable for the description of molecular mobility and orientational ordering only for relatively low sample temperatures and low-mobility probe molecules with large sizes. In cases of high molecular mobility, the more realistic jump mechanism of molecular moves can be approximately described as quasi-librations. For ordered liquid crystals it was found that mostly the order parameters up to rank 12-14 are essential and easily determined. When well-aligned materials are described, the order parameters up to 18th rank or even higher become meaningful. Both molecular and sample biaxiality is analyzed and quantitatively characterized. The local molecular ordering and sample orientational alignment are quantitatively characterized separately.
RESUMO
A defensive dominant was created in rabbits using rhythmic electrocutaneous stimulation of the left forelimb at a frequency of 0.5 Hz. After stimulation ended, the latent excitation state was tested using sound stimuli. Animals responded either with increases in non-rhythmic paw muscle activity or with rhythmic twitching of the paw at a frequency close to that of the electrocutaneous stimulation. After hypnotization, the incidence of rhythmic responses to the stimulation testing the dominant focus increased, while the incidence of non-rhythmic responses decreased.
Assuntos
Condicionamento Clássico/fisiologia , Resposta de Imobilidade Tônica/fisiologia , Córtex Motor/fisiologia , Contração Muscular/fisiologia , Inibição Neural/fisiologia , Reconhecimento Fisiológico de Modelo/fisiologia , Animais , Estimulação Elétrica , Membro Anterior , Lateralidade Funcional/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Periodicidade , CoelhosRESUMO
Light microscopy methods were used to study the main stages in the organogenesis of the pituitary in human embryos at Carnegie stages (CS) 12-23. Rathke's pouch (RP) was shown to form as a traction fold over whole width of the roof of the stomodeum in embryos at CS 12 due to a flexure of the neural tube with which the epithelium had a tight anatomical relationship (the attached part of the anterior wall of the RP) in the median plane of the embryo. The rudiment of the hypothalamic infundibulum and neurohypophysis formed at CS 15, as a thickening of the posterior wall of the diencephalon. Transorientation of the positions of brain components, including the rudiment of the hypophysis, occurred at CS 20-23. The attached part of the anterior wall of the RP then formed the pars intermedia and pars tuberalis of the anterior lobe, while the epithelium of the orifice of the RP and its posterior wall formed the pars distalis. From CS 20 to 23, the RP epithelium formed the structural-functional units of the adenohypophysis, i.e., the epithelial cords, by invagination.
Assuntos
Hipófise/embriologia , Diencéfalo/anatomia & histologia , Diencéfalo/embriologia , Desenvolvimento Embrionário , Epitélio/embriologia , Feminino , Feto/anatomia & histologia , Humanos , Neurônios/fisiologia , Hipófise/citologia , Adeno-Hipófise/embriologia , Neuro-Hipófise/embriologia , GravidezRESUMO
A hidden excitation focus (dominanta focus) was produced in the rabbit's CNS by threshold electrical stimulation of the left forelimb with the frequency of 0.5 Hz. As a rule, after the formation of the focus, pairs of neurons with prevailing two-second rhythm in their correlated activity were revealed both in the left and right sensorimotor cortices (with equal probabilities 29.3 and 32.4%, respectively). After "animal hypnosis" induction, the total percent of neuronal pairs with the prevalent dominanta-induced rhythm decreased significantly only in the right hemisphere (21%). After the termination of the "animal hypnosis" state, percent of neuronal pairs in the right cortex with prevailing two-second rhythm significantly increasead if the neurons in a pair were neighboring and decreased if they were remote from each other. Similar changes after the hypnotization were not found in the left cortex. Analysis of correlated activity of neuronal pairs with regard to amplitude characteristics showed that for both the right and left hemispheres, the prevalence of the two-second rhythm was more frequently observed in crosscorrelation histograms constructed regarding discharges of neurons with the lowest spike amplitude (in the right hemisphere) or the lowest and mean amplitudes (in the left hemisphere) selected from multiunit records.