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1.
Averaging of EEG of interstimulus intervals in the process of study of habituation of auditory evoked potentials (EPs) in healthy subjects and patients with endogenous depression, revealed a rhythmic wave process (RWP) especially expressed in patients. RWP appeared and became stronger in successive averaging of 10 realizations completing each of four series of 30 clicks; often (especially in depressive patients) it was manifest in averaging of all 120 realizations with an amplitude comparable with that of main EPs components and even greater. A significant correlation was found of RWP parameters with characteristics of melancholic mood in both subgroups. It is suggested that RWP appears as a result of regular changes of EEG background during multiple stimuli repetition in connection with increased "slow" habituation and in a special manifestation of perceptive defence during depression including mechanisms of active isolation from external world.  相似文献   

2.
Sex differences of hemisphere asymmetry of homo- and heterotopic transcallosal responses in association cortex of 48 cats (24 male and 24 female) immobilized by tubocurarine have been studied by means of topographic EPs recordings in both hemispheres. In males left hemisphere dominates by the amplitude of homotopic and positive wave of heterotopic EPs and right hemisphere dominates by the amplitude of negative wave of heterotopic sensorimotor cortex EPs. The individual asymmetry of EPs has been observed in sensomotor cortex of females and in parietal cortex of animals of both sex. The interhemispheric asymmetry is expressed distinctly in females than in males. It is concluded that sex dimorphism is present in functional organization of associative system of (callosal and intracortical) connections in cat's neocortex projection and association areas which means its more expressed hemisphere lateralization in males with more expressed interhemispheric asymmetry of functional transcallosal connections in females.  相似文献   

3.
Modification of the viscerosensory evoked potentials (EPs) were studied during the sleep-wakefulness cycle of the rat. Electrical stimuli of various intensity were delivered either to the mucosal surface of a fistula of the small intestine or to the left splanchnic nerve during wakefulness (W), drowsiness (D), slow-wave-sleep (SWS), and paradoxical sleep (PS). The average EPs were recorded from the somatosensory (SI and SII) and associative (AS) areas of the cortex, the ventrobasal complex of the thalamus (VPL), the posterior hypothalamus (HPT) and the dorsal hippocampus (HPC). The amplitude of each component of the EPs in all explored structures were the largest in SWS and the smallest in W. A phasic increase in amplitude was observed in the EPs recorded immediately before the appearance of the spindles of SWS and during the REM episodes of PS. The peak latencies of the late components were the longest in SWS. These changes of the amplitudes and latencies were greater in the responses to weak stimulation than in EPs to strong ones. The possible synaptic events of the sleep-dependent control of viscerosensory activity are discussed.  相似文献   

4.
We have identified adenovirus type 2 (Ad2)-induced early polypeptides (EPs) and have attempted to determine which EPs are coded by each of the four early gene blocks. [35S]methionine-labeled EPs were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cycloheximide pretreatment followed by labeling in hypertonic medium (210 to 250 mM NaCl) facilitated the detection of EPs. Seven major (reproducible bands in autoradiograms) EPs were detected with molecular weights of 74,000 (74K), 21K, 19K, 15K, 13.5K, 11.5K, and 11K. Minor (weaker bands) EPs of 55K, 52K, 42K, 18K, 12K, 8.8K, and 8.3K were also often seen. To identify and map the genes for virus-coded EPs, we prepared antisera against five lines of adenovirus-transformed cells that retain different fractions of the viral genome. The lines were F17, 8617, F4, and T2C4 transformed by Ad2 virions and 5RK (clone I) transformed by transfection with the Ad5 HsuI-G fragment (map position 0 to 8). The early gene blocks retained and expressed (in part) as RNA in these cells were as follows: 5RK(I), block 1 (70% of left 8% of genome); F17, block 1; 8617, blocks 1 and 4; F4 blocks 1, 2, and 4; T2C4, blocks 1, 2, 3, and 4. The following major EPs were immunoprecipitated: 15K by all antisera; 53K and 14.5K by F17, T2C4, 8617, and F4 antisera; 11.5K by T2C4, 8617, and F4 antisera; 44K, 42K, 19K, and 13.5K by T2C4 antisera; 11K by 8617 antisera. Minor EPs of 28K, 18K, and 12K were precipitated by all antisera except 5RK(I). The 53K and 15K EPs were precipitated also from Ad2 early infected monkey cells by the F17 antiserum and by sera from hamsters bearing tumors induced by Ad1-simian virus 40. The relationships between some of the immunoprecipitated EPs were investigated by the partial proteolysis procedure. All 53K EPs are the "same" (i.e., highly related), all 15K EPs are the "same," and all 11.5K EPs are the "same." The 15K EP is highly related to the 14.5 K EP. Although less certain, all 28K EPs appeared related, as did all 18K EPs. The T2C4-specific 44K EP is probably a dimer of the 21K glycopolypeptide. The T2C4-specific 13.5K EP and the 8617-specific 11K EP appear unrelated to any other polypeptides. These immunoprecipitation data provide evidence that early gene block I (map position 1 to 11) may encode major 53K, 15K, and 14.5K polypeptides, and minor 28K, 18K, and 12K polypeptides, and that all or some of the gene for 15K and 14.5K lies within map position 1 to 8. The surprisingly complex pattern of polypeptides coded by early gene block I raises the possibility that some polypeptides may be coded by overlapping "spliced" mRNA's. The possible block locations of the genes for the 21K, 13.5K, and 11.5K polypeptides are discussed.  相似文献   

5.
Molecular subtyping is used to distinguish pathogenic bacterial strains during epidemiological surveys of infectious diseases and the discovery of novel pathogens. There is a need to standardize protocols involving Pulse-Field Gel Electrophoresis (PFGE), a crucial method in molecular subtyping, to make inter-laboratory results comparable and information exchange possible. The PFGE pattern varies with electrophoretic parameters (EPs), so it is important to select the parameter that can distinguish the patterns better. To optimize EPs of PFGE for Vibrio cholerae, we analyzed 24 isolates of V. cholerae O1 biotype El Tor and 26 isolates of O139 by PFGE with Not|. We used four different EPs and compared the similarity coefficients from the four groups by Friedman test. Based on the principle that the electrophoretic parameter producing smaller similarity in the PFGE patterns has higher level of discriminatory power, the one producing the smallest similarity coefficients is considered to be optimal. This method could be applied to determine the optimal molecular subtyping protocol for other bacteria.  相似文献   

6.
Somatosensory and visual evoked potentials (EPs) of the brain of 17 sensitive subjects (extrasenses) and 12 ordinary healthy subjects were studied. It was found that during extrasensory activity (direct impact, meditation) in comparison to rest values, the amplitude of intermediate and late components of visual and somatosensory EPs of both hemispheres and early components of somatosensory EPs of ipsilateral in relation to stimulation hemisphere diminished 2-4--fold. There was a recovery of these components after discontinuation of extrasensory activity. It is shown that ordinary subjects could not change their EPs when they tried their best to decrease EPs. It is shown that ordinary subjects could not change their EPs when they tried their best to decrease EPs. It is suggested that the ability of extrasenses for reversible changes of their mind by direct adjustment of the activity of the ascending nonspecific systems of the brain and by alterations of interhemispheric relations forms the basis of extrasensory activity.  相似文献   

7.
Following the bipolar stimulation of the vesico-urethral junction (VUJ), evoked potentials (EPs) with a late and prominent negativity (mean latency 91.4 ± 11.0 msec) were recorded from scalp in 22 male subjects. Although remarkable intersubject variations occurred, no peak variation could be seen in any given subject. Maximum amplitude of the EPs was recorded from Cz and CzP points. Stimuli with various frequencies did not lead to any differences in shape and latency of EPs.The differences between the EPs by bipolar stimulation of the VUJ and the responses elicited by distal urethal and pudendal nerve stimulation suggest that, during bipolar stimulation of VUJ, the somatic afferents were not excited. Therefore, these responses were most likely due to the excitement of the visceral afferents arising from the VUJ separately. This method may be a useful technique for evaluating the physiological condition of the afferent nerves arising from VUJ.  相似文献   

8.
Pelargonium sidoides is a medical herb and respective extracts are used very frequently for the treatment of respiratory tract infections. However, the effects of Pelargonium sidoides and a special extract prepared from its roots (EPs 7630) on human immune cells are not fully understood. Here we demonstrate that EPs 7630 induced a rapid and dose-dependent production of TNF-α, IL-6, and IL-10 by human blood immune cells. This EPs 7630-induced cytokine profile was more pro-inflammatory in comparison with the profile induced by viral or bacterial infection-mimicking agents. The search for EPs 7630 target cells revealed that T-cells did not respond to EPs 7630 stimulation by production of TNF-α, IL-6, or IL-10. Furthermore, pretreatment of T-cells with EPs 7630 did not modulate their TNF-α, IL-6, and IL-10 secretion during subsequent activation. In contrast to lymphocytes, monocytes showed clear intracellular TNF-α staining after EPs 7630 treatment. Accordingly, EPs 7630 predominantly provoked activation of MAP kinases and inhibition of p38 strongly reduced the monocyte TNF-α production. The pretreatment of blood immune cells with EPs 7630 lowered their secretion of TNF-α and IL-10 and caused an IL-6 dominant response during second stimulation with viral or bacterial infection-mimicking agents. In summary, we demonstrate that EPs 7630 activates human monocytes, induces MAP kinase-dependent pro-inflammatory cytokines in these cells, and specifically modulates their production capacity of mediators known to lead to an increase of acute phase protein production in the liver, neutrophil generation in the bone marrow, and the generation of adaptive Th17 and Th22 cells.  相似文献   

9.
Evoked responses (EPs) of the auditory and the sensorimotor cortical areas were studied in experiments on cats during formation of a positive food-procuring conditioned reflex to a rhythmic sequence of clicks and during formation of the differentiation inhibition in response to the clicks of the same parameters, but with different frequency. In the positive conditioned reflex the EPs amplitude in the sensorimotor cortex increases; they are enriched by late components and in their general configuration they become much similar to EPs in the auditory area. The EPs patterns both in the auditory and in the sensorimotor areas considerably change in response to the differentiation stimulus, but differently in each of the sites.  相似文献   

10.
In our companion paper, the physiological functions of pancreatic β cells were analyzed with a new β-cell model by time-based integration of a set of differential equations that describe individual reaction steps or functional components based on experimental studies. In this study, we calculate steady-state solutions of these differential equations to obtain the limit cycles (LCs) as well as the equilibrium points (EPs) to make all of the time derivatives equal to zero. The sequential transitions from quiescence to burst-interburst oscillations and then to continuous firing with an increasing glucose concentration were defined objectively by the EPs or LCs for the whole set of equations. We also demonstrated that membrane excitability changed between the extremes of a single action potential mode and a stable firing mode during one cycle of bursting rhythm. Membrane excitability was determined by the EPs or LCs of the membrane subsystem, with the slow variables fixed at each time point. Details of the mode changes were expressed as functions of slowly changing variables, such as intracellular [ATP], [Ca(2+)], and [Na(+)]. In conclusion, using our model, we could suggest quantitatively the mutual interactions among multiple membrane and cytosolic factors occurring in pancreatic β cells.  相似文献   

11.
The visual evoked potentials (EPs) in response to lateralized and central visual symbols under the conditions of involuntary (passive viewing) and selective attention (when one of the symbols was a target and required a rapid and precise motor reaction) are considered. The evoked potentials in the occipital, parietal, and frontal derivations were recorded in 20 healthy subjects. It was shown that the EP during selective attention are most pronounced and more alike in the parietal derivations. A strong positive correlation was revealed between the EP amplitude ([N1–P3] component) and the EP stability (correlation between the repeated EP). The involuntary and voluntary forms of attention supplement each other: the more expressed the involuntary attention (assessed by the [N1–P3] component) the higher the EP to target stimuli during voluntary attention and the shorter the reaction time. It is suggested that the role of visual attention consists in the increase and stabilization of cortical activity (primarily, the parietal regions) engaged in solving a visual task.  相似文献   

12.
Yang C  Liu X  Cao Q  Liang Q  Qiu X 《Life sciences》2011,88(5-6):201-205
Prostaglandin E receptors (EPs) are the G-protein-coupled receptors (GPCRs) that respond to type E(2) prostaglandin (PGE(2)). Data has shown that PGE(2) may function as an endogenous anti-inflammatory mediator by suppressing the production of cytokines. However, other studies have demonstrated that PGE(2), a pro-inflammatory mediator produced by various cell types within the wounded vascular wall, plays a crucial role in early atherosclerotic development. These contradictory results may be due to the versatility of EPs. Experimental data suggest an individual role for each PGE(2) receptor, such as EP(1), EP(2), EP(3) and EP(4), in atherosclerosis. In this review, the roles of EPs in atherosclerosis are summarized, and the value of EPs as new therapeutic targets for atherosclerosis is explored.  相似文献   

13.
The crystallized structure of adult zebra finch (Taeniopygia guttata) song is modifiable if sensory feedback is altered during sound production. Such song plasticity has been studied by examining acoustic modifications to the motif; however, the underlying changes to the vocal motor patterns of these acoustic modifications have not been addressed. Adult birds in two age categories (young=90-120 days or middle aged 150-250 days) that sang crystallized song were used in the experiment. Vocal motor patterns were monitored by recording respiratory air sac pressure before, during, and after song plasticity was induced by partial or complete reduction of phonation (i.e., "partial muting"). Birds were recorded until changes in air sac pressure patterns underlying the song structure were observed (up to 160 days). Young adult birds were more likely to insert shorter duration (<125 ms) expiratory pulses (EPs) into the motif than middle-aged adults. These shorter duration EPs were produced with a unique pressure pattern relative to the intact song, and therefore appeared to be generated by novel motor gestures. Stuttering (atypical repetition of an EP) was observed when these novel EPs were inserted into the motif, regardless of age. The EP of the distance call, which is also a learned vocalization in zebra finches, showed a similar reduction in duration if EPs were also shortened in the song. The emergence of shorter duration EPs was not related to sound production, or nonspecific effects of the surgical procedure, which suggests an age-dependent neural process for song plasticity.  相似文献   

14.
The crystallized structure of adult zebra finch (Taeniopygia guttata) song is modifiable if sensory feedback is altered during sound production. Such song plasticity has been studied by examining acoustic modifications to the motif; however, the underlying changes to the vocal motor patterns of these acoustic modifications have not been addressed. Adult birds in two age categories (young = 90–120 days or middle aged 150–250 days) that sang crystallized song were used in the experiment. Vocal motor patterns were monitored by recording respiratory air sac pressure before, during, and after song plasticity was induced by partial or complete reduction of phonation (i.e., “partial muting”). Birds were recorded until changes in air sac pressure patterns underlying the song structure were observed (up to 160 days). Young adult birds were more likely to insert shorter duration (<125 ms) expiratory pulses (EPs) into the motif than middle‐aged adults. These shorter duration EPs were produced with a unique pressure pattern relative to the intact song, and therefore appeared to be generated by novel motor gestures. Stuttering (atypical repetition of an EP) was observed when these novel EPs were inserted into the motif, regardless of age. The EP of the distance call, which is also a learned vocalization in zebra finches, showed a similar reduction in duration if EPs were also shortened in the song. The emergence of shorter duration EPs was not related to sound production, or nonspecific effects of the surgical procedure, which suggests an age‐dependent neural process for song plasticity. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2004  相似文献   

15.

Background

Non-invasive prenatal testing of trisomy 21 (T21) is being actively investigated using fetal-specific epigenetic markers (EPs) that are present in maternal plasma. Recently, 12 EPs on chromosome 21 were identified based on tissue-specific epigenetic characteristics between placenta and blood, and demonstrated excellent clinical performance in the non-invasive detection of fetal T21. However, the disease-specific epigenetic characteristics of the EPs have not been established. Therefore, we validated the disease-specific epigenetic characteristics of these EPs for use in non-invasive detection of fetal T21.

Methods

We performed a high-resolution tiling array analysis of human chromosome 21 using a methyl-CpG binding domain-based protein (MBD) method with whole blood samples from non-pregnant normal women, whole blood samples from pregnant normal women, placenta samples of normal fetuses, and placenta samples of T21 fetuses. Tiling array results were validated by bisulfite direct sequencing and qPCR.

Results

Among 12 EPs, only four EPs were confirmed to be hypermethylated in normal placenta and hypomethylated in blood. One of these four showed a severe discrepancy in the methylation patterns of T21 placenta samples, and another was located within a region of copy number variations. Thus, two EPs were confirmed to be potential fetal-specific markers based on their disease-specific epigenetic characteristics. The array results of these EPs were consisted with the results obtained by bisulfite direct sequencing and qPCR. Moreover, the two EPs were detected in maternal plasma.

Conclusions

We validated that two EPs have the potential to be fetal-specific EPs which is consistent with their disease-specific epigenetic characteristics. The findings of this study suggest that disease-specific epigenetic characteristics should be considered in the development of fetal-specific EPs for non-invasive prenatal testing of T21.  相似文献   

16.
Experiments were performed in 13 chloralose-anaesthetized, curarized cat preparations (monitoring of rectal temperature, heart rate, expired pCO2 and EEG), in order to ascertain whether, and to what extent, the reactivity to ipsilateral skin shocks of the neurones of the anterior ectosylvian and anterior suprasylvian gyri (AEG and ASG, respectively) is dependent on the callosal output of the somatosensory areas of the contralateral hemisphere. Indeed, we knew from previous experiments that a high proportion of AEG and ASG neurones having bilateral peripheral receptive fields (PRFs) can be excited by direct stimulation of the contralateral homonymous areas, and that the callosal fibres originating in the latter carry somesthetic impulses related to contralateral PRFs. A preliminary analysis was carried out on the amplitude and latency relationships between the evoked potentials (EP) recorded simultaneously from the two hemispheres and from the corpus callosum (CC) following stimulation of the forepaw of one side. The results obtained showed good correlations between the onset and development of the EPs picked up from the hemisphere ipsilateral to the stimulated skin, on the one hand, and onset and development of the EPs recorded from the contralateral hemisphere and the corpus callosum, on the other. At a further stage of the experiments, the EPs elicited upon ipsilateral and contralateral skin shocks in the AEG-ASG area have been recorded and averaged before, during and after the reversible inactivation of callosal somesthetic transmission. This was achieved by applying polarizing currents (0.2-1 mA) to the rostral portion of the CC, adequacy and reversibility of this method having been tested by observing, respectively, suppression and prompt restoration of transcallosal EPs and of the asynaptic spiking produced by cortical cells when antidromically invaded from contralateral homotopic cortex. It was seen that during CC blockade the EPs elicited in the AEG-ASG areas did not show any change either in amplitude or time-course if brought about by contralateral peripheral stimulation, whereas those evoked by ipsilateral skin shocks exhibited significant reduction, which was related to the strength of CC polarization and to the reduction of transcallosal EPs. In control experiments similar effects were observed after ablation of somatosensory areas of the hemisphere which send off somesthetic callosal impulses, whereas strychninization of these areas caused effects opposite in sign, i.e., enhancement of the ipsilateral but not of the contralateral EPs in the areas of the untreated hemisphere. By testing the effects of CC polarization on single AEG-ASG neurones, it was observed that the responses of units linked only with contralateral PRFs (Group I; 7 units tested) were unaffected by callosal polarization. The discharges of neurones provided with wide and bilateral PRFs (Group II; 27 units tested) were not affected if elicited by contralateral PRF shocks but were deeply impaired (in 11 neurones out the 27) when provoked by ipsilateral PRF stimulation. The effect consisted chiefly of the disappearance of the first high peak of the PSTHs, and when recording intracellularly graded events, it was mirrored by a large decrease of the postsynaptic excitatory potentials elicited in Group II neurones by ipsilateral PRF shocks. A late scattered histographic component was identified in the PSTHs of such cells, which did not appear to be significantly altered during CC blockade. These effects were observed on the ipsilateral responses of 11 out of the 27 Group II neurones so tested whereas the ipsilateral PSTHs of the remaining 16 Group II neurones either did not undergo significant changes during the callosal blockade or escaped evaluation because of high spontaneous shifts of neural responsiveness. The results are discussed mainly with a view to the possible functional role of the specific somesthetic callosal fibres in defining ipsilateral reactivity for the wide-field cells of the AEG-ASG area.  相似文献   

17.
Visual evoked potentials (EPs) of the left and right hemispheres in response to relevant and irrelevant stimuli in the structures of the left and right hemispheres have been studied in healthy young schoolchildren, learning-disabled (LD) children, and mentally retarded (MR) children. In healthy children, the largest EP variations depending on the stimulus relevancy have been found in associative structures of the left hemisphere. In LD children of the same age, the amplitude and temporal characteristics of left-hemispheric EPs to target and nontarget stimuli are the same. In MR children, EPs to relevant and irrelevant stimuli do not differ from each other in either the left or the right hemisphere. EP latencies are significantly longer in MR children than in healthy children. The results of simultaneous recording of EPs in the left and right hemispheres during isolated stimulation of the right and left visual half-fields indicate that interhemispheric interaction is impaired in children with deviations in mental development. The results of the study are discussed in terms of the psychological characteristics and learning ability of children.  相似文献   

18.
Activation of lipolysis by cyclic AMP in conditions with accelerated lipid mobilization was examined in subcutaneous adipose tissue incubated in vitro. In (a) 16 obese patients before and during therapeutic starvation, (b) 18 diabetics before and after antidiabetic treatment and (c) 11 hyperthyroid patients before and after anti-thyroid treatment, a positive correlation was found between stimulation of basal cyclic AMP accumulation and stimulation of basal glycerol release using either isopropyl noradrenaline or noradrenaline (r = 0.6-0.9). During antidiabetic treatment stimulation of lipolysis increased in relation to that of cyclic AMP accumulation (F = 10.1, p less than 0.01), whereas during antithyroid therapy there was a decrease (F = 95.2, p less than 0.01). Starvation did not alter the relationship between lipolysis and cyclic AMP in hypogastric adipose tissue whereas in femoral tissue stimulation of lipolysis decreased in relation to that of cyclic AMP accumulation (F = 9.6, p less than 0.01). It is concluded that the amount of cyclic AMP needed to promote lipolysis is increased during starvation and in diabetes mellitus but is decreased in hyperthyroidism. From the studies during starvation it appears that regional differences in the post-receptor activation of lipolysis exist in human adipose tissue.  相似文献   

19.
Selective attention can be focused either volitionally, by top-down signals derived from task demands, or automatically, by bottom-up signals from salient stimuli. Because the brain mechanisms that underlie these two attention processes are poorly understood, we recorded local field potentials (LFPs) from primary visual cortical areas of cats as they performed stimulus-driven and anticipatory discrimination tasks. Consistent with our previous observations, in both tasks, we found enhanced beta activity, which we have postulated may serve as an attention carrier. We characterized the functional organization of task-related beta activity by (i) cortical responses (EPs) evoked by electrical stimulation of the optic chiasm and (ii) intracortical LFP correlations. During the anticipatory task, peripheral stimulation that was preceded by high-amplitude beta oscillations evoked large-amplitude EPs compared with EPs that followed low-amplitude beta. In contrast, during the stimulus-driven task, cortical EPs preceded by high-amplitude beta oscillations were, on average, smaller than those preceded by low-amplitude beta. Analysis of the correlations between the different recording sites revealed that beta activation maps were heterogeneous during the bottom-up task and homogeneous for the top-down task. We conclude that bottom-up attention activates cortical visual areas in a mosaic-like pattern, whereas top-down attentional modulation results in spatially homogeneous excitation.  相似文献   

20.
The character of evoked potentials (EPs) dynamics to signal light stimulus during elaboration of avoidance reaction, allows to assert that during formation of adaptive activity functional balance is established of sensory and integrative-triggering brain parts or functional balance of "motor" and "sensory" integration regimes. Each of the studied subcortical structures is characterized by simultaneous but specific functioning both in the motor and sensory regimes; such conclusion is based on different dynamics of their EPs parameters: the changes of ones correspond to EPs dynamics in the visual cortical area, of the others--in the motor area. During chronic haloperidol administration, the reorganizations of intercentral relations are observed in 10--12 days after the beginning of drug administration. They may be considered as a succession of disturbances of functional balance between "sensory" and "motor" integration regimes: at first the sensory regime domination appears in which subcortical structures are chiefly and uniformly involved (ncd, pall and n. acc.); "motor" regime is weakened; then, as a result, a distortion of the "motor" regime of integration takes place. In this case a bradykinesia is developed.  相似文献   

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