Development of metabolic activity patterns in the somatosensory cortex of cats

1. The development of cortical responses to somatic stimulation was studied in kittens 2-5 wk of age using the 2-deoxyglucose (2DG) technique. During the 2DG experiment each kitten received an innocuous intermittent vertical displacement stimulus to the forepaw. 2. The pattern of metabolic activity was substantially different in young animals compared with adults. In the individual autoradiographs of the 2-wk-old kittens stimulus-evoked 2DG uptake in primary somatosensory cortex was localized to a small spot in the upper portion of the cortex, whereas in the adult the label extended vertically through the cortical layers and appeared more column-like. Individual patches of label were substantially smaller and less dense in young animals. Over a period of several weeks the evoked activity evolved to the more extensive adult pattern. The 2DG uptake displayed a mature distribution by approximately 4-5 wk of age. During this period, the cortical architecture also evolved from an immature to a mature arrangement. 3. The evoked activity was reconstructed into two-dimensional maps; the distribution of label > or = 1.5 SD above background was considered to be stimulus related. In the adult, the pattern appeared as a strip or strips of increased metabolic activity that extended in the rostrocaudal direction for approximately 1 mm. In contrast, the activity pattern in animals 2-4 wk old was less discretely organized into "strips" and was more diffusely spread over several mms of somatosensory cortex. The two-dimensional pattern gradually coalesced into a more localized strip by approximately 4-5 wk of age. Although the pattern of label was more widespread in the young animals, the absolute distance of the spread of activity did not vary substantially, regardless of the age of the animal. 4. Other measurements regarding the distribution of activity at different ages indicate that the amount of cortex activated increases in absolute terms, although the percent of cortex activated by the stimulus decreases. The overall intensity of the 2DG uptake as measured on the two-dimensional maps increases with age, as does the variability of the 2DG uptake; a wider range of intensity values is seen in the adult. Plots created from the individual two-dimensional reconstructions allowed a measure of "patch strength" at different ages. These histograms relate the most intense region of uptake in a given map to the spatial distribution of activity spreading in the medial and lateral directions.(ABSTRACT TRUNCATED AT 400 WORDS)

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Developmental regulation of plasticity in cat somatosensory cortex

Journal of Neurophysiology ◽

10.1152/jn.1994.72.4.1706 ◽

1994 ◽

Vol 72 (4) ◽

pp. 1706-1716 ◽

Cited By ~ 8

Author(s):

S. L. Juliano ◽

D. E. Eslin ◽

M. Tommerdahl

Keyword(s):

Somatosensory Cortex ◽

Sensory Input ◽

Developmental Regulation ◽

Normal Pattern ◽

Metabolic Pattern ◽

Somatosensory Cortices ◽

Experimental Side ◽

Adult Cats ◽

Evoked Activity ◽

The Individual

1. The neocortical response to deprivation of somatic sensory input in young animals of different ages was compared with the same manipulation in adults. The response was measured through the use of 2-deoxyglucose (2DG) mapping. Although several features of the cortical response were similar in animals of all ages, the metabolic patterns evoked by somatic stimulation differed substantially from each other at all ages. 2. When adult cats receive a digit amputation and survive from 2 to 8 wk, the pattern of stimulus-evoked metabolic uptake expands dramatically in the somatosensory cortex contralateral to the deprived forepaw. Comparisons between the normal and experimental somatosensory cortices reveal that the distribution of activity on the experimental side was roughly an expanded version of the normal pattern. 3. Unilateral digit amputations of digit 2 were conducted on kittens 2, 4, or 6 wk old. They survived until 3–4 mo and then received a 2DG experiment, during which digit 3 was stimulated bilaterally. Evaluation of the evoked metabolic pattern indicated substantial differences from the activity elicited in adults undergoing identical manipulations. 4. The individual patches of activity that made up the metabolic pattern were similar in intensity in both hemispheres when the digit amputation was conducted at either 2, 4, or 6 wk. After a digit amputation at 2 wk, the patches were significantly narrower in the experimental hemisphere; after a digit amputation at 6 wk, the patches were significantly wider in the hemisphere receiving from the deprived forepaw. 5. Two-dimensional maps of 2DG uptake in areas 3b and 1 of the somatosensory cortex reveal that after a digit amputation at 2, 4, or 6 wk, the distribution of activity in the hemisphere receiving from the digit amputation was more dispersed and widespread than in the normal hemisphere. The dispersed pattern of uptake was not an expanded version of the normal pattern, but scattered over a wider region of somatosensory cortex. This observation is similar to the normal pattern of evoked activity seen in developing animals. 6. The total area of 2DG uptake in the somatosensory cortex contralateral to a digit amputation conducted at 2 or 4 wk was not greater than that in the normal hemisphere, even though it was more widespread. After a digit amputation at 6 wk, however, the area of evoked activity was greater in the experimental hemisphere but not of the magnitude as the same manipulation in an adult.(ABSTRACT TRUNCATED AT 400 WORDS)

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Metabolic Activity Patterns in the Monkey Visual Cortex as Revealed by Spectral Analysis

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-199904000-00006 ◽

1999 ◽

Vol 19 (4) ◽

pp. 401-416 ◽

Cited By ~ 1

Author(s):

Yannis Dalezios ◽

Georgia G. Gregoriou ◽

Helen E. Savaki

Keyword(s):

Spectral Analysis ◽

Visual Cortex ◽

Metabolic Activity ◽

Activity Patterns ◽

Spatial Arrangement ◽

Spectral Amplitude ◽

Two Dimensional ◽

Reaching Task ◽

Area V2 ◽

Monkey Visual Cortex

The metabolic activity pattern of the monkey visual cortex was mapped quantitatively with [14C]-2-deoxyglucose during the performance of a visually guided reaching task. After bandpass filtering of the reconstructed two-dimensional metabolic maps of areas V1 and V2, alternating bands of high and low metabolic activity were apparent in control and experimental hemispheres. The spatial arrangement of active bands was studied with two-dimensional spectral analysis, and bands were found to be more organized in the experimental monkey. In area V1 of the control monkey the spectral amplitude was spread over a wider range of directions and frequencies than in the experimental subject. The finding that layer IV is characterized by more complex spectra than layers I through III suggests the coexistence of more than one active columnar system in the geniculorecipient layer. In area V2, stripes running almost perpendicular to the V1/V2 border were found along with superimposed patches of enhanced metabolic activity. In the experimental hemispheres, the corresponding spectra were extremely sharp yielding a constant periodicity. It is suggested that the well-organized columnar arrangement within areas V1 and V2 of the experimental hemispheres emerges from the diffusely organized background network of activity patterns in the control state.

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In VitroAnalyses of the Effects of Heparin and Parabens on Candida albicans Biofilms and Planktonic Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05061-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 148-153 ◽

Cited By ~ 15

Author(s):

Marisa H. Miceli ◽

Stella M. Bernardo ◽

T. S. Neil Ku ◽

Carla Walraven ◽

Samuel A. Lee

Keyword(s):

Candida Albicans ◽

Metabolic Activity ◽

Biofilm Formation ◽

High Dose ◽

Dependent Manner ◽

Planktonic Cells ◽

Content Type ◽

Heparin Sodium ◽

The Individual

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.

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The Concept of Accuracy Analysis of the Vertical Displacements Gained from the Hydrostatic Levelling Systems’ Measurements

Sensors ◽

10.3390/s21144842 ◽

2021 ◽

Vol 21 (14) ◽

pp. 4842

Author(s):

Waldemar Kamiński

Keyword(s):

Accuracy Assessment ◽

Theoretical Models ◽

Vertical Displacement ◽

Serial Connection ◽

Vertical Displacements ◽

Comprehensive Determination ◽

The One ◽

The Individual ◽

Reference Sensor

Nowadays, hydrostatic levelling is a widely used method for the vertical displacements’ determinations of objects such as bridges, viaducts, wharfs, tunnels, high buildings, historical buildings, special engineering objects (e.g., synchrotron), sports and entertainment halls. The measurements’ sensors implemented in the hydrostatic levelling systems (HLSs) consist of the reference sensor (RS) and sensors located on the controlled points (CPs). The reference sensor is the one that is placed at the point that (in theoretical assumptions) is not a subject to vertical displacements and the displacements of controlled points are determined according to its height. The hydrostatic levelling rule comes from the Bernoulli’s law. While using the Bernoulli’s principle in hydrostatic levelling, the following components have to be taken into account: atmospheric pressure, force of gravity, density of liquid used in sensors places at CPs. The parameters mentioned above are determined with some mean errors that influence on the accuracy assessment of vertical displacements. In the subject’s literature, there are some works describing the individual accuracy analyses of the components mentioned above. In this paper, the author proposes the concept of comprehensive determination of mean error of vertical displacement (of each CPs), calculated from the mean errors’ values of components dedicated for specific HLS. The formulas of covariances’ matrix were derived and they enable to make the accuracy assessment of the calculations’ results. The author also presented the subject of modelling of vertical displacements’ gained values. The dependences, enabling to conduct the statistic tests of received model’s parameters, were implemented. The conducted tests make it possible to verify the correctness of used theoretical models of the examined object treated as the rigid body. The practical analyses were conducted for two simulated variants of sensors’ connections in HLS. Variant no. I is the sensors’ serial connection. Variant no. II relies on the connection of each CPs with the reference sensor. The calculations’ results show that more detailed value estimations of the vertical displacements can be obtained using variant no. II.

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Studies on the structure and function of the mammalian testis V. Steroid metabolism by isolated interstitium and seminiferous tubules of the human testis

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1974.0041 ◽

1974 ◽

Vol 186 (1083) ◽

pp. 99-120 ◽

Cited By ~ 8

Keyword(s):

Metabolic Activity ◽

General Pattern ◽

Steroid Metabolism ◽

Human Testis ◽

Clinical Aspects ◽

Seminiferous Tubules ◽

Bicarbonate Buffer ◽

The Media ◽

The Individual ◽

And Function

Tissue was obtained from the testes of three men, two in the age range 72-75 years (subjects A and B) and one aged 25 years (subject C). Parts of the testes were dissected to obtain samples of interstitium and tubules. The individual components and whole tissue were each incubated with equimolar concentrations of [7 α - 3 H]pregnenolone and [4- 14 C]progesterone in Krebs-Ringer bicarbonate buffer pH 7.4, at 35 °C with the addition of glucose but without cofactors. Some incubations were carried out with the substrates [4- 14 C]androstenedione and [7 α - 3 H]testosterone. The media were extracted both at various time intervals throughout the incubation for a kinetic study of the metabolic activity and after a fixed interval of time at the end of the incubations. In some incubations with whole tissue both media and tissue were extracted. Both the tubules and interstitium displayed steroid metabolic activity. Qualitatively they yielded the same range of metabolites, one series leading to the formation of testosterone (∆ 5 pathway) and the other to a variety of C 21 compounds as represented by 5 α -pregnan-3 β -ol-20-one. With similar amounts of tissue there was little difference in the yields of the main products formed by the tubules as compared with those formed by the interstitium; in incubations with [4- 14 C]androstenedione the rate of conversion to [ 14 C ]testosterone by the tubules greatly exceeded that due to the interstitium. Marked differences were found in the pattern of steroid metabolism by whole tissue as compared to the general pattern presented by the corresponding tubules and interstitium. It is concluded that the seminiferous tubules and interstitium of the human testis are both capable of steroid metabolism and hence that whole tissue incubations alone are of limited value and could give rise to misleading data. Some clinical aspects of the results are briefly discussed.

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A STUDY OF TWO‐DIMENSIONAL HEAD WAVES IN FLUID AND SOLID SYSTEMS

Geophysics ◽

10.1190/1.1439230 ◽

1963 ◽

Vol 28 (4) ◽

pp. 563-581 ◽

Cited By ~ 7

Author(s):

John W. Dunkin

Keyword(s):

Half Space ◽

Vertical Displacement ◽

Point Of View ◽

Head Wave ◽

Apparent Velocity ◽

Two Dimensional ◽

Multiple Reflections ◽

Transient Wave ◽

Line Load ◽

Head Waves

The problem of transient wave propagation in a three‐layered, fluid or solid half‐plane is investigated with the point of view of determining the effect of refracting bed thickness on the character of the two‐dimensional head wave. The “ray‐theory” technique is used to obtain exact expressions for the vertical displacement at the surface caused by an impulsive line load. The impulsive solutions are convolved with a time function having the shape of one cycle of a sinusoid. The multiple reflections in the refracting bed are found to affect the head wave significantly. For thin refracting beds in the fluid half‐space the character of the head wave can be completely altered by the strong multiple reflections. In the solid half‐space the weaker multiple reflections affect both the rate of decay of the amplitude of the head wave with distance and the apparent velocity of the head wave by changing its shape. A comparison is made of the results for the solid half‐space with previously published results of model experiments.

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Fluorescence analysis of the metabolic activity patterns of a neuronal–glial network

Journal of Optical Technology ◽

10.1364/jot.79.000348 ◽

2012 ◽

Vol 79 (6) ◽

pp. 348 ◽

Cited By ~ 5

Author(s):

Yu. N. Zakharov ◽

E. V. Mitroshina ◽

M. V. Vedunova ◽

S. A. Korotchenko ◽

Ya. I. Kalintseva ◽

...

Keyword(s):

Metabolic Activity ◽

Activity Patterns ◽

Fluorescence Analysis

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Iron compounds in the heart-body of the terebellid polychaete Neoamphitrite figulus

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400054874 ◽

1965 ◽

Vol 45 (2) ◽

pp. 341-351 ◽

Cited By ~ 15

Author(s):

R. Phillips Dales

Keyword(s):

Metabolic Activity ◽

Iron Compounds ◽

Iron Protein ◽

Different Ages ◽

Different Seasons ◽

Haem Iron ◽

By Products

The heart-body contains haematins derived from by-products of haem synthesis. It also contains a non-haem iron protein and a flavin. Study of the relative amounts of these substances in worms of different ages and at different seasons suggests that the flavin plays some part in the metabolic activity of the organ and that the haematins accumulate throughout life. No evidence was found for the heart-body participating in any excretory activity or in haemoglobin breakdown.

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Quality Assessment of Globally Available Digital Elevation Model (DEM) for Mountainous Region

Journal of Geographical Studies ◽

10.21523/gcj5.21050102 ◽

2021 ◽

Vol 5 (1) ◽

pp. 11-21

Author(s):

Sangay Gyeltshen ◽

Krisha Kumar Subedi ◽

Laylo Zaridinova Kamoliddinovna ◽

Jigme Tenzin

Keyword(s):

Digital Elevation Model ◽

Vertical Displacement ◽

Satellite System ◽

Topographic Map ◽

Alos Palsar ◽

Aster Gdem ◽

Digital Elevation ◽

The Government ◽

Elevation Model ◽

The Individual

The study assessed the accuracies of globally available Digital Elevation Models (DEM’s) i.e., SRTM v3, ASTER GDEM v2 and ALOS PALSAR DEM with respect to Topo-DEM derived from topographic map of 5m contour interval. 100 ground control points of the elevation data were collected with the help of kinematic hand held GNSS (Global Navigation Satellite System), randomly distributed over the study area. The widely used RMSE statistic, NCC correlation and sub-pixel-based approach were applied to evaluate the erroneous, correlation, horizontal and vertical displacement in terms of pixels for the individual Digital Elevation Model. Following these evaluations, SRTM DEM was found to be highly accurate in terms of RMSE and displacement compared to other DEMs. This study is intended to provide the researchers, GIS specialists and the government agencies dealing with remote sensing and GIS, a basic clue on accuracy of the DEMs so that the best model can be selected for application on various purposes of the similar region.

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