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Sample records for ca1 perforant path

  1. The role of the direct perforant path input to the CA1 subregion of the dorsal hippocampus in memory retention and retrieval.

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    Vago, David R; Bevan, Adam; Kesner, Raymond P

    2007-01-01

    Subregional analyses of the hippocampus have suggested a selective role for the CA1 subregion in intermediate/long-term spatial memory and consolidation, but not short-term acquisition or encoding processes. It remains unclear how the direct cortical projection to CA1 via the perforant path (pp) contributes to these CA1-dependent processes. It has been suggested that dopamine selectively modulates the pp projection to CA1 while having little to no effect on the Schaffer collateral (SC) projection to CA1. This series of behavioral and electrophysiological experiments takes advantage of this pharmacological dissociation to demonstrate that the direct pp inputs to CA1 are critical in CA1-dependent intermediate-term retention and retrieval function. Here we demonstrate that local infusion of the nonselective dopamine agonist, apomorphine (10, 15 microg), into the CA1 subregion of awake animals produces impairments in between-day retention and retrieval, sparing within-day encoding of a modified Hebb-Williams maze and contextual conditioning of fear. In contrast, apomorphine produces no deficits when infused into the CA3 subregion. To complement the behavioral analyses, electrophysiological data was collected. In anesthetized animals, local infusion of the same doses of apomorphine significantly modifies evoked responses in the distal dendrites of CA1 following angular bundle stimulation, but produces no significant effects in the more proximal dendritic layer following stimulation of the SC. These results support a modulatory role for dopamine in the EC-CA1, but not CA3-CA1 circuitry, and suggest the possibility of a more fundamental role for EC-CA1 synaptic transmission in terms of intermediate-term, but not short-term spatial memory.

  2. Disruption of the direct perforant path input to the CA1 subregion of the dorsal hippocampus interferes with spatial working memory and novelty detection.

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    Vago, David R; Kesner, Raymond P

    2008-06-03

    Subregional analyses of the hippocampus suggest CA1-dependent memory processes rely heavily upon interactions between the CA1 subregion and entorhinal cortex. There is evidence that the direct perforant path (pp) projection to CA1 is selectively modulated by dopamine while having little to no effect on the Schaffer collateral (SC) projection to CA1. The current study takes advantage of this pharmacological dissociation to demonstrate that local infusion of the non-selective dopamine agonist, apomorphine (10, 15 microg), into the CA1 subregion of awake animals produces impairments in working memory at intermediate (5 min), but not short-term (10 s) delays within a delayed non-match-to-place task on a radial arm maze. Sustained impairments were also found in a novel context with similar object-space relationships. Infusion of apomorphine into CA1 is also shown here to produce deficits in spatial, but not non-spatial novelty detection within an object exploration paradigm. In contrast, apomorphine produces no behavioral deficits when infused into the CA3 subregion or overlying cortex. These behavioral studies are supported by previous electrophysiological data that demonstrate local infusion of the same doses of apomorphine significantly modifies evoked responses in the distal dendrites of CA1 following angular bundle stimulation, but produces no significant effects in the proximal dendritic layer following stimulation of the SC. These results support a modulatory role for dopamine in EC-CA1, but not CA3-CA1 circuitry, and suggest the possibility of a fundamental role for EC-CA1 synaptic transmission in terms of detection of spatial novelty, and intermediate-term, but not short-term spatial working memory or object-novelty detection.

  3. Parvalbumin disappears from GABAergic CA1 neurons of the gerbil hippocampus with seizure onset while its presence persists in the perforant path.

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    Scotti, A L; Kalt, G; Bollag, O; Nitsch, C

    1997-06-20

    Mongolian gerbils are epilepsy prone animals, a trait observable at the behavioural level during the 2nd month of life. As a unique species difference, gerbils express the calcium-binding protein parvalbumin (PV) in the perforant path from the entorhinal cortex to the hippocampus. In this study, we determined the time of appearance of PV in the layer II neurons of the entorhinal cortex and the perforant path terminals in gerbils between post-natal days 30 and 50. Signs of low grade seizures were observed in few animals from P40 onward. PV stain in the entorhinal cortex and perforant path terminals was already detectable at P30, well before the onset of behavioural seizures and did not change with age. It is suggested that the presence of PV in this pathway may be related to the generation early in life of an epileptogenic focus in the limbic forebrain. Altered inhibitory hippocampal circuits have also been suggested as a cause of seizures in the gerbil. Therefore, we quantitated hippocampal GABA-immunoreactive neurons and the PV-immunoreactive subpopulation. A group of gerbils with a high density of stained pyramidal interneurons in CA1 and one lacking PV-stained perikarya could be distinguished at P40 and P50. The density of GABA-immunoreactive nerve cells however, remained the same in both groups and through the ages studied. Thus, perikaryal PV is lost from intact GABAergic nerve cells at the same time as behavioural seizures are observed. The loss of PV from GABAergic neurons may affect their functional properties and be instrumental for the maintainance of behavioural seizures.

  4. Perforant path transection induces complement C9 deposition in hippocampus.

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    Johnson, S a; Young-Chan, C S; Laping, N J; Finch, C E

    1996-04-01

    The presence of complement system proteins in amyloid plaques and the up-regulation of several complement mRNAs in neurons and glial cells in affected brain regions during Alzheimer disease (AD) provided a basis for further examination of complement protein expression in a rodent lesion model of AD. Perforant path transection in rats was used as a model for the degeneration of entorhinal cortex (EC) layer II neurons and the consequent deafferentation of the hippocampus that occurs during AD. Immunostaining for C9, a key terminal component of the complement cascade membrane attack complex (MAC), showed extracellular C9 deposition in parenchyma around the EC wound and in hippocampus as early as 1 day, and disappeared by 14 days postlesion. Apoptosis of EC layer II neurons was seen and was presumably due to severing of their axonal projections to the hippocampus by the transection lesion. However, apoptotic EC layer II neurons were not immunostained by anti-rat C9 antibody, suggesting complement was not involved in inducing apoptosis. In the deafferented hippocampus, extracellular C9 immunostaining was localized to the dentate gyrus middle molecular layer, a region of synaptic loss, dendritic degeneration, and early synaptogenesis. In addition, intracellular C9 immunostaining was seen only in select hippocampal interneurons. Dentate gyrus granule neurons and pyramidal neurons were not C9 immunostained. Clusterin (SGP-2), a soluble inhibitor of the MAC that is up-regulated in AD, was also detected in the wound area (extracellular), the dentate gyrus middle molecular layer (extracellular), and intracellularly in scattered hippocampal interneurons. The data support the hypothesis that the complement system generally participates in responses to brain injury, as well as in AD.

  5. Flow Behavior in Z-Path Fluidized-Moving Bed with Inclined Perforated Plate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The flow behaviors in a gas-solid contactor with inclined perforated plates that form a zigzag path were experimentally studied. In this contactor solid particles slide down along the inclined perforated plates by the upflowing gas. This structure, called as "z-path-moving bed", has some of the advantages of both moving and fluidized beds. The discharge rate of solid particles, inclination angle of the perforated plate, aperture ratio of the perforated plate, size of particles and gas velocity were chosen as parameters for experimental conditions. The stable operation conditions were certained for the particles and apparatus used. The pressure drop, bed height and residence time distribution of particles were measured versus gas velocity.

  6. Mnemonic discrimination relates to perforant path integrity: An ultra-high resolution diffusion tensor imaging study.

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    Bennett, Ilana J; Stark, Craig E L

    2016-03-01

    Pattern separation describes the orthogonalization of similar inputs into unique, non-overlapping representations. This computational process is thought to serve memory by reducing interference and to be mediated by the dentate gyrus of the hippocampus. Using ultra-high in-plane resolution diffusion tensor imaging (hrDTI) in older adults, we previously demonstrated that integrity of the perforant path, which provides input to the dentate gyrus from entorhinal cortex, was associated with mnemonic discrimination, a behavioral outcome designed to load on pattern separation. The current hrDTI study assessed the specificity of this perforant path integrity-mnemonic discrimination relationship relative to other cognitive constructs (identified using a factor analysis) and white matter tracts (hippocampal cingulum, fornix, corpus callosum) in 112 healthy adults (20-87 years). Results revealed age-related declines in integrity of the perforant path and other medial temporal lobe (MTL) tracts (hippocampal cingulum, fornix). Controlling for global effects of brain aging, perforant path integrity related only to the factor that captured mnemonic discrimination performance. Comparable integrity-mnemonic discrimination relationships were also observed for the hippocampal cingulum and fornix. Thus, whereas perforant path integrity specifically relates to mnemonic discrimination, mnemonic discrimination may be mediated by a broader MTL network.

  7. Coincidence detection of convergent perforant path and mossy fibre inputs by CA3 interneurons.

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    Calixto, Eduardo; Galván, Emilio J; Card, J Patrick; Barrionuevo, Germán

    2008-06-01

    We performed whole-cell recordings from CA3 s. radiatum (R) and s. lacunosum-moleculare (L-M) interneurons in hippocampal slices to examine the temporal aspects of summation of converging perforant path (PP) and mossy fibre (MF) inputs. PP EPSPs were evoked from the s. lacunosum-moleculare in area CA1. MF EPSPs were evoked from the medial extent of the suprapyramidal blade of the dentate gyrus. Summation was strongly supralinear when examining PP EPSP with MF EPSP in a heterosynaptic pair at the 10 ms ISI, and linear to sublinear at longer ISIs. This pattern of nonlinearities suggests that R and L-M interneurons act as coincidence detectors for input from PP and MF. Summation at all ISIs was linear in voltage clamp mode demonstrating that nonlinearities were generated by postsynaptic voltage-dependent conductances. Supralinearity was not detected when the first EPSP in the pair was replaced by a simulated EPSP injected into the soma, suggesting that the conductances underlying the EPSP boosting were located in distal dendrites. Supralinearity was selectively eliminated with either Ni2+ (30 microm), mibefradil (10 microm) or nimodipine (15 microm), but was unaffected by QX-314. This pharmacological profile indicates that supralinearity is due to recruitment of dendritic T-type Ca2+channels by the first subthreshold EPSP in the pair. Results with the hyperpolarization-activated (Ih) channel blocker ZD 7288 (50 microm) revealed that Ih restricted the time course of supralinearity for coincidently summed EPSPs, and promoted linear to sublinear summation for asynchronous EPSPs. We conclude that coincidence detection results from the counterbalanced activation of T-type Ca2+ channels and inactivation of Ih.

  8. Priming stimulation modifies synaptic plasticity in the perforant path of hippocampal slice in rat

    Institute of Scientific and Technical Information of China (English)

    Lian ZHANG; Hong-Mei XIAO; Yan-Xia ZHOU; Xiao-Ping LUO

    2006-01-01

    Objective The potential of all central nervous system synapses to exhibit long term potentiation (LTP) or long term depression (LTD) is subject to modulation by prior synaptic activity, a higher-order form of plasticity that has been termed metaplasticity. This study is designed to examine the plasticity and metaplasticity in the lateral perforant path of rat. Methods Field potential was measured with different priming and conditioning stimulation protocols. Results Ten-hertz priming, which does not affect basal synaptic transmission, caused a dramatic reduction in subsequent LTP at lateral perforant path synapses in vitro, and the reduced LTP lasted for at least 2 h. The LTD was unaffected. The reduction of LTP in the lateral perforant path was also readily induced by applying priming antidromically at the mossy fibers. Conclusion Priming with 10 Hz, which is within a frequency range observed during physiological activity, can cause potent,long-lasting inhibition of LTP, but not LTD. This form of metaplasticity adds a layer of complexity to the activity-dependent modification of synapses within the dentate gyrus.

  9. Increased synthesis of heparin affin regulatory peptide in the perforant path lesioned mouse hippocampal formation

    DEFF Research Database (Denmark)

    Poulsen, F R; Lagord, C; Courty, J

    2000-01-01

    axonal sprouting within the perforant path zones of the fascia dentata and hippocampus as well as axotomy-induced retrograde neuronal degeneration in the entorhinal cortex. Analysis of sham- and unoperated control mice showed that HARP mRNA is expressed in neurons and white and gray matter glial cells...... as well as vascular and pial cells throughout the normal, adult brain. Lesioning induced high levels of HARP mRNA in astroglial-like cells in the denervated zones of fascia dentata and hippocampus as soon as day 2 postlesion. This expression reached maximum at day 4, and declined toward normal at day 7....... Finally, the axotomized entorhinal layer II neurons, which expressed high levels of HARP mRNA in the normal brain, exhibited a marked decline in hybridization signal after axotomy. The induction of high levels of HARP mRNA and protein in astrocytes in the denervated areas of fascia dentata and hippocampus...

  10. Investigating the Anticonvulsant Effects of Repetitive Transcranial Magnetic Stimulation on Perforant Path Kindling Model in Rats

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    Ali Yadollahpour

    2015-02-01

    Full Text Available Background: Almost 20% of epileptics are drug resistant. Studies have shown that low frequency repetitive transcranial magnetic stimulation (rTMS is with therapeutic effects on epilepsy-affected laboratory models. Anticonvulsant effects of rTMS depend on several parameters among which radiation frequency is the most important one. In this study, the therapeutic impacts of 1 and 2 Hz rTMS on convulsing parameters in epileptic model of electrical kindling stimulation of the perforant path were investigated. Materials and Methods: In this experimental study 21 rats were randomly divided into three groups, namely ‘1 Hz treatment group’ and ‘2 Hz treatment group’ and ‘kindling group’. The kindling group only received kindling stimulations for seven days. One Hz and 2 Hz frequency treatment groups received maximally 5 min rTMS after termination of kindling stimulation per day for a week. Stimulation and stability electrodes had been placed, in turn, on perforant path and dentate gyrus. For quantifying the duration of the subsequent discharge waves, two-way ANOVA test and Bonferroni post-test were employed. In addition, for quantifying the convulsive behaviors, Kruskal-Wallis and the Mann-Whitney U tests were used. Results: The results showed that 1 Hz and 2 Hz frequency rTMS have considerable inhibitory impact on the development of convulsive phases. Anticonvulsive effect was observed from the first day after rTMS was undertaken. In addition, the animals did not show fourth and fifth convulsive stages, and a significant reduction was evident in their recorded peak discharge waves compared with kindle group. Conclusion: Low frequency rTMS possesses significant anticonvulsive effects which depend upon sTMS stimulation frequency.

  11. Chronic Fluoxetine Induces the Enlargement of Perforant Path-Granule Cell Synapses in the Mouse Dentate Gyrus.

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    Kitahara, Yosuke; Ohta, Keisuke; Hasuo, Hiroshi; Shuto, Takahide; Kuroiwa, Mahomi; Sotogaku, Naoki; Togo, Akinobu; Nakamura, Kei-ichiro; Nishi, Akinori

    2016-01-01

    A selective serotonin reuptake inhibitor is the most commonly prescribed antidepressant for the treatment of major depression. However, the mechanisms underlying the actions of selective serotonin reuptake inhibitors are not fully understood. In the dentate gyrus, chronic fluoxetine treatment induces increased excitability of mature granule cells (GCs) as well as neurogenesis. The major input to the dentate gyrus is the perforant path axons (boutons) from the entorhinal cortex (layer II). Through voltage-sensitive dye imaging, we found that the excitatory neurotransmission of the perforant path synapse onto the GCs in the middle molecular layer of the mouse dentate gyrus (perforant path-GC synapse) is enhanced after chronic fluoxetine treatment (15 mg/kg/day, 14 days). Therefore, we further examined whether chronic fluoxetine treatment affects the morphology of the perforant path-GC synapse, using FIB/SEM (focused ion beam/scanning electron microscopy). A three-dimensional reconstruction of dendritic spines revealed the appearance of extremely large-sized spines after chronic fluoxetine treatment. The large-sized spines had a postsynaptic density with a large volume. However, chronic fluoxetine treatment did not affect spine density. The presynaptic boutons that were in contact with the large-sized spines were large in volume, and the volumes of the mitochondria and synaptic vesicles inside the boutons were correlated with the size of the boutons. Thus, the large-sized perforant path-GC synapse induced by chronic fluoxetine treatment contains synaptic components that correlate with the synapse size and that may be involved in enhanced glutamatergic neurotransmission.

  12. Enduring medial perforant path short-term synaptic depression at high pressure

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    Adolfo E Talpalar

    2010-10-01

    Full Text Available The high pressure neurological syndrome develops during deep diving (> 1.1 MPa involving impairment of cognitive functions, alteration of synaptic transmission and increased excitability in cortico-hippocampal areas. The medial perforant path (MPP, connecting entorhinal cortex with the hippocampal formation, displays synaptic frequency-dependent-depression (FDD under normal conditions. Synaptic FDD is essential for specific functions of various neuronal networks. We used rat cortico-hippocampal slices and computer simulations for studying the effects of pressure and its interaction with extracellular Ca2+ ([Ca2+]o on FDD at the MPP synapses. At atmospheric pressure, high [Ca2+]o (4-6 mM saturated single MPP field EPSP (fEPSP and increased FDD in response to short trains at 50 Hz. High pressure (HP; 10.1 MPa depressed single fEPSPs by 50 %. Increasing [Ca2+]o to 4 mM at HP saturated synaptic response at a subnormal level (only 20 % recovery of single fEPSPs, but generated a FDD similar to atmospheric pressure. Mathematical model analysis of the fractions of synaptic resources used by each fEPSP during trains (normalized to their maximum and the total fraction utilized within a train indicate that HP depresses synaptic activity also by reducing synaptic resources. This data suggest that MPP synapses may be modulated, in addition to depression of single events, by reduction of synaptic resources and then may have the ability to conserve their dynamic properties under different conditions.

  13. The temporoammonic input to the hippocampal CA1 region displays distinctly different synaptic plasticity compared to the Schaffer collateral input in vivo: significance for synaptic information processing

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    Ayla eAksoy Aksel

    2013-08-01

    Full Text Available In terms of its sub-regional differentiation, the hippocampal CA1 region receives cortical information directly via the perforant (temporoammonic path (pp-CA1 synapse and indirectly via the tri-synaptic pathway where the last relay station is the Schaffer collateral-CA1 synapse (Sc-CA1 synapse. Research to date on pp-CA1 synapses has been conducted predominantly in vitro and never in awake animals, but these studies hint that information processing at this synapse might be distinct to processing at the Sc-CA1 synapse. Here, we characterized synaptic properties and synaptic plasticity at the pp-CA1 synapse of freely behaving adult rats. We established that field excitatory postsynaptic potentials at the pp-CA1 have longer onset latencies and a shorter time-to-peak compared to the Sc-CA1 synapse. LTP (> 24h was successfully evoked by tetanic afferent stimulation of pp-CA1 synapses. Low frequency stimulation evoked synaptic depression at Sc-CA1 synapses, but did not elicit LTD at pp-CA1 synapses unless the Schaffer collateral afferents to the CA1 region had been severed. Paired-pulse responses also showed significant differences. Our data suggest that synaptic plasticity at the pp-CA1 synapse is distinct from the Sc-CA1 synapse and that this may reflect its specific role in hippocampal information processing.

  14. The temporoammonic input to the hippocampal CA1 region displays distinctly different synaptic plasticity compared to the Schaffer collateral input in vivo: significance for synaptic information processing

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    Aksoy-Aksel, Ayla; Manahan-Vaughan, Denise

    2013-01-01

    In terms of its sub-regional differentiation, the hippocampal CA1 region receives cortical information directly via the perforant (temporoammonic) path (pp-CA1 synapse) and indirectly via the tri-synaptic pathway where the last relay station is the Schaffer collateral-CA1 synapse (Sc-CA1 synapse). Research to date on pp-CA1 synapses has been conducted predominantly in vitro and never in awake animals, but these studies hint that information processing at this synapse might be distinct to processing at the Sc-CA1 synapse. Here, we characterized synaptic properties and synaptic plasticity at the pp-CA1 synapse of freely behaving adult rats. We observed that field excitatory postsynaptic potentials at the pp-CA1 synapse have longer onset latencies and a shorter time-to-peak compared to the Sc-CA1 synapse. LTP (>24 h) was successfully evoked by tetanic afferent stimulation of pp-CA1 synapses. Low frequency stimulation evoked synaptic depression at Sc-CA1 synapses, but did not elicit LTD at pp-CA1 synapses unless the Schaffer collateral afferents to the CA1 region had been severed. Paired-pulse responses also showed significant differences. Our data suggest that synaptic plasticity at the pp-CA1 synapse is distinct from the Sc-CA1 synapse and that this may reflect its specific role in hippocampal information processing. PMID:23986697

  15. Reduction of rat hippocampal calcium-binding protein following commissural, amygdala, septal, perforant path, and olfactory bulb kindling.

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    Baimbridge, K G; Mody, I; Miller, J J

    1985-01-01

    The calcium-binding protein (CaBP) content of the hippocampal formation was determined by radioimmunoassay in control and kindled rats. Kindling of a number of different sites resulted in a reduction in the CaBP content of the hippocampal formation, which was shown immunohistochemically to be restricted to the dentate granule cells and their processes. The maximum decline in CaBP varied with the different kindling sites: perforant path, 33%; commissural path, 32%; septum, 30%; amygdala, 18%; and olfactory bulbs, 15%. There were no changes in the CaBP content of the stimulated areas themselves. In cases where the kindling stimulus was delivered unilaterally (perforant path and amygdala), the maximum decrease in hippocampal CaBP was observed ipsilateral to the site of stimulation when the criterion for full kindling was established (six consecutive stage 5 motor seizures). Further kindling trials were required to produce a similar magnitude decrease in the CaBP content of the contralateral hippocampus. These observations are discussed both in relation to the possible role of CaBP in the establishment of a seizure response to kindling and also as a potential compensatory mechanism that may serve to overcome the epileptogenic effects of kindling.

  16. Convergence of entorhinal and CA3 inputs onto pyramidal neurons and interneurons in hippocampal area CA1--an anatomical study in the rat.

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    Kajiwara, Riichi; Wouterlood, Floris G; Sah, Anupam; Boekel, Amber J; Baks-te Bulte, Luciënne T G; Witter, Menno P

    2008-01-01

    The entorhinal cortex (EC) conveys information to hippocampal field CA1 either directly by way of projections from principal neurons in layer III, or indirectly by axons from layer II via the dentate gyrus, CA3, and Schaffer collaterals. These two pathways differentially influence activity in CA1, yet conclusive evidence is lacking whether and to what extent they converge onto single CA1 neurons. Presently we studied such convergence. Different neuroanatomical tracers injected into layer III of EC and into CA3, respectively, tagged simultaneously the direct entorhino-hippocampal fibers and the indirect innervation of CA1 neurons by Schaffer collaterals. In slices of fixed brains we intracellularly filled CA1 pyramidal cells and interneurons in stratum lacunosum-moleculare (LM) and stratum radiatum (SR). Sections of these slices were scanned in a confocal laser scanning microscope. 3D-reconstruction was used to determine whether boutons of the labeled input fibers were in contact with the intracellularly filled neurons. We analyzed 12 pyramidal neurons and 21 interneurons. Perforant path innervation to pyramidal neurons in our material was observed to be denser than that from CA3. All pyramidal neurons and 17 of the interneurons received contacts of both perforant pathway and Schaffer input on their dendrites and cell bodies. Four interneurons, which were completely embedded in LM, received only labeled perforant pathway input. Thus, we found convergence of both projection systems on single CA1 pyramidal and interneurons with dendrites that access the layers where perforant pathway fibers and Schaffer collaterals end.

  17. Microglial reactivity correlates to the density and the myelination of the anterogradely degenerating axons and terminals following perforant path denervation of the mouse fascia dentata

    DEFF Research Database (Denmark)

    Jensen, M B; Hegelund, I V; Rom Poulsen, Frantz

    1999-01-01

    Transection of the entorhino-dentate perforant path is a well known model for lesion-induced axonal sprouting and glial reactions in the rat. In this study, we have characterized the microglial reaction in the dentate molecular layer of the SJL/J and C57Bl/6 mouse. The morphological transformatio...

  18. Testicular hormones do not regulate sexually dimorphic Pavlovian fear conditioning or perforant-path long-term potentiation in adult male rats.

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    Anagnostaras, S G; Maren, S; DeCola, J P; Lane, N I; Gale, G D; Schlinger, B A; Fanselow, M S

    1998-04-01

    We recently reported that Pavlovian fear conditioning and hippocampal perforant-path long-term potentiation (LTP) are sexually dimorphic in rats. Males show greater contextual fear conditioning, which depends on the hippocampus, as well as greater hippocampal LTP. In order to examine the role of circulating gonadal hormones in adult male rats, animals were castrated in two experiments, and Pavlovian fear conditioning and in vivo perforant-path LTP were examined. It was found that sexually-dimorphic LTP and fear conditioning are not regulated by the activational effects of testicular hormones in adult male rats. That is, in every respect, castrated male rats were similar to intact male rats in Pavlovian fear conditioning and hippocampal LTP. It is likely that sexual dimorphism in this system is established earlier in development by the organizational effects of gonadal hormones.

  19. Effect of low-frequency electrical stimulation parameters on its anticonvulsant action during rapid perforant path kindling in rat.

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    Shahpari, Marzieh; Mirnajafi-Zadeh, Javad; Firoozabadi, Seyed Mohammad P; Yadollahpour, Ali

    2012-03-01

    Low frequency stimulation (LFS) may be considered as a new potential therapy for drug-resistant epilepsy. However, the relation between LFS parameters and its anticonvulsant effects is not completely determined. In this study, the effect of some LFS parameters on its anticonvulsant action was investigated in rats. In all animals, stimulating and recording electrodes were implanted into the perforant path and dentate gyrus, respectively. In one group of animals, kindling stimulations were applied until rats achieved a fully kindled state. In other groups, different patterns of LFS were applied at the end of kindling stimulations during twenty consecutive days. In the first experiment the effect of LFS pulse numbers was investigated on its anticonvulsant action. Animals were divided randomly into three groups and 1, 4, and 8 packages of LFS (each pack contains 200 pulses, 0.1 ms pulse duration at 1 Hz) were applied five minutes after termination of kindling stimulations. Obtained results showed that 4 packages of LFS had the strongest anticonvulsant effects. Therefore, this pattern (4 packages) was used in the next experiment. In the second experiment, 4 packages of LFS were applied at intervals of 30 s and 30 min after termination of kindling stimulations. The strongest anticonvulsant effect was observed in the group received LFS at the interval of 30 s. Therefore, this pattern was selected for the third experiment. In the third experiment the effect of LFS at frequencies of 0.25 Hz and 5 Hz was investigated. The group of animals which received LFS at the frequency of 0.25 Hz showed somehow stronger anticonvulsant effect. The results indicate that different parameters of LFS have important role in induction of LFS anticonvulsant effects. Regarding this view, it seems that the slower LFS frequency and the shorter interval between LFS and kindling stimulations, the stronger anticonvulsant effect will be observed. But there is no direct relation between number of

  20. Distinct behavioral phenotypes in novel "fast" kindling-susceptible and "slow" kindling-resistant rat strains selected by stimulation of the hippocampal perforant path.

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    Langberg, Tomer; Dashek, Ryan; Mulvey, Bernard; Miller, Kimberly A; Osting, Susan; Stafstrom, Carl E; Sutula, Thomas P

    2016-01-01

    Kindling is a phenomenon of activity-dependent neural circuit plasticity induced by repeated seizures that results in progressive permanent increases in susceptibility to epilepsy. As the permanent structural and functional modifications induced by kindling include a diverse range of molecular, cellular, and functional alterations in neural circuits, it is of interest to determine if genetic background associated with seizure-induced plasticity might also influence plasticity in neural circuitry underlying other behaviors. Outbred Sprague-Dawley (SD) rats were selected and bred for ~15 generations for "fast' or "slow" rates of kindling development in response to stimulation of the perforant path input to the hippocampus. After 7-8 generations of selection and breeding, consistent phenotypes of "fast" and "slow" kindling rates were observed. By the 15th generation "fast" kindling rats referred to as Perforant Path Kindling Susceptible (PPKS) rats demonstrated a kindling rate of 10.7 ± 1.1 afterdischarges (ADs) to the milestone of the first secondary generalized (Class V) seizure, which differed significantly from "slow" kindling Perforant Path Kindling Resistant (PPKR) rats requiring 25.5 ± 2.0 ADs, and outbred SD rats requiring 16.8 ± 2.5 ADs (pkindling) strain with increased susceptibility to seizure-induced plasticity demonstrated statistically significant increases in motor exploratory activity in the open field test and reduced spatial learning the Morris water maze, but demonstrated normal fear conditioned learning comparable to outbred SD rats and the "slow" kindling-resistant PPKR strain. These results confirm that selection and breeding on the basis of responses to repeated pathway activation by stimulation can produce enduring modification of genetic background influencing behavior. These observations also suggest that genetic background underlying susceptibility or resistance to seizure-induced plasticity in hippocampal circuitry also differentially

  1. Brain-derived neurotrophic factor infusion delays amygdala and perforant path kindling without affecting paired-pulse measures of neuronal inhibition in adult rats.

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    Osehobo, P; Adams, B; Sazgar, M; Xu, Y; Racine, R J; Fahnestock, M

    1999-01-01

    Kindling is an animal model of human temporal lobe epilepsy in which excitability in limbic structures is permanently enhanced by repeated stimulations. Kindling also increases the expression of nerve growth factor, brain-derived neurotrophic factor, and brain-derived neurotrophic factor receptor messenger RNAs in both the hippocampus and cerebral cortex and causes structural changes in the hippocampus including hilar hypertrophy. We have recently shown that intraventricular nerve growth factor infusion enhances the development of kindling, whereas blocking nerve growth factor activity retards amygdaloid kindling. Furthermore, we have shown that nerve growth factor protects against kindling-induced hilar hypertrophy. The physiological role of brain-derived neurotrophic factor in kindling is not as clear. Acute injection of brain-derived neurotrophic factor increases neuronal excitability and causes seizures, whereas chronic brain-derived neurotrophic factor infusion in rats slows hippocampal kindling. In agreement with the latter, we show here that intrahilar brain-derived neurotrophic factor infusion delays amygdala and perforant path kindling. In addition, we show that brain-derived neurotrophic factor, unlike nerve growth factor, does not protect against kindling-induced increases in hilar area. To test the hypothesis that brain-derived neurotrophic factor suppresses kindling by increasing inhibition above normal levels, we performed paired-pulse measures in the perforant path-dentate gyrus pathway. Brain-derived neurotrophic factor infused into the hippocampus had no effect on the stimulus intensity function (input/output curves); there was also no significant effect on paired-pulse inhibition. We then kindled the perforant path 10 days after the end of brain-derived neurotrophic factor treatment. Once again, kindling was retarded, showing that the brain-derived neurotrophic factor effect is long-lasting. These results indicate that prolonged in vivo infusion

  2. Long-term fluoxetine treatment induces input-specific LTP and LTD impairment and structural plasticity in the CA1 hippocampal subfield.

    Directory of Open Access Journals (Sweden)

    Francisco J Rubio

    2013-05-01

    Full Text Available Antidepressant drugs are usually administered for long time for the treatment of major depressive disorder. However, they are also prescribed in several additional psychiatric conditions as well as during long term maintenance treatments. Antidepressants induce adaptive changes in several forebrain structures which include modifications at glutamatergic synapses. We recently found that repetitive administration of the selective serotonin reuptake inhibitor fluoxetine to naϊve adult male rats induced an increase of mature, mushroom-type dendritic spines in several forebrain regions. This was associated with an increase of GluA2-containing α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptors (AMPA-Rs in telencephalic postsynaptic densities. To unravel the functional significance of such a synaptic re-arrangement, we focused on glutamate neurotransmission in the hippocampus. We evaluated the effect of four weeks of treatment with 0.7 mg/kg of fluoxetine on long-term potentiation (LTP and long-term depression (LTD in the Schaffer collateral-CA1 synapses and the perforant path-CA1 synapses. Recordings in hippocampal slices revealed profound deficits in LTP and LTD at Schaffer collateral-CA1 synapses associated to increased spine density and enhanced presence of mushroom-type spines, as revealed by Golgi staining. However, the same treatment had neither an effect on spine morphology, nor on LTP and LTD at perforant path-CA1 synapses. Cobalt staining experiments revealed decreased AMPA-R Ca2+ permeability in the stratum radiatum together with increased GluA2-containing, Ca2+-impermeable AMPA-Rs. Therefore, 4 weeks of fluoxetine treatment promoted structural and functional adaptations in CA1 neurons in a pathway-specific manner that were selectively associated with impairment of activity-dependent plasticity at Schaffer collateral-CA1 synapses.

  3. Cholinergic modulation of excitatory synaptic input integration in hippocampal CA1.

    Science.gov (United States)

    McQuiston, A Rory

    2010-10-01

    During theta rhythm, the timing of inputs to hippocampal CA1 from the perforant path (PP) of the entorhinal cortex and the Schaffer collaterals (SCs) from individual CA3 pyramidal neurons can vary within an individual theta period. Importantly, during theta rhythms these interactions occur during elevated acetylcholine concentrations. Thus, I examined the effect that PP inputs have on SC inputs in hippocampal CA1 during cholinergic receptor activation. To do this I measured the impact that a single electrical stimulus of the stratum lacunosum-moleculare (SLM, which contains the PP) had on excitation evoked by stimulation of the stratum radiatum (SR, which contains the SC) using voltage-sensitive dye imaging, field excitatory postsynaptic potentials and whole cell patch clamping in rat hippocampal brain slices. My data showed that SLM stimulation one half a theta cycle or less (25-75 ms) before SR stimulation resulted in the summation of excitatory events in SR and SP of hippocampal CA1. The summation was unaffected by cholinergic receptor activation by carbachol. SLM stimulation one theta cycle (150-225 ms) preceding SR stimulation significantly suppressed excitatory events measured in SR and SP. This SLM stimulus inhibition of SR-driven excitatory events was augmented by carbachol application. The carbachol effect was blocked by atropine and SLM-driven suppression of excitatory events was blocked by the GABA(B) receptor antagonist CGP 54626. SR field EPSP slopes were unaffected by SLM prepulses. Carbachol increased the probability of SR input to drive action potential firing in CA1 pyramidal neurons, which was inhibited by SLM prepulses (150-225 ms). Together these data provide important information regarding the integration of inputs in hippocampal CA1 during theta rhythms. More specifically, SR inputs can be differentially gated by SLM feedforward inhibition at varying temporal intervals within a theta cycle.

  4. Regional differences in GABAergic modulation for TEA-induced synaptic plasticity in rat hippocampal CA1, CA3 and dentate gyrus.

    Science.gov (United States)

    Suzuki, Etsuko; Okada, Takashi

    2007-10-01

    Tetraethylammonium (TEA), a K(+)-channel blocker, reportedly induces long-term potentiation (LTP) of hippocampal CA1 synaptic responses, but at CA3 and the dentate gyrus (DG), the characteristics of TEA-induced plasticity and modulation by inhibitory interneurons remain unclear. This study recorded field EPSPs from CA1, CA3 and DG to examine the involvement of GABAergic modulation in TEA-induced synaptic plasticity for each region. In Schaffer collateral-CA1 synapses and associational fiber (AF)-CA3 synapses, bath application of TEA-induced LTP in the presence and absence of picrotoxin (PTX), a GABA(A) receptor blocker, whereas TEA-induced LTP at mossy fiber (MF)-CA3 synapses was detected only in the absence of GABA(A) receptor blockers. MF-CA3 LTP showed sensitivity to Ni(2+), but not to nifedipine. In DG, synaptic plasticity was modulated by GABAergic inputs, but characteristics differed between the afferent lateral perforant path (LPP) and medial perforant path (MPP). LPP-DG synapses showed TEA-induced LTP during PTX application, whereas at MPP-DG synapses, TEA-induced long-term depression (LTD) was seen in the absence of PTX. This series of results demonstrates that TEA-induced DG and CA3 plasticity displays afferent specificity and is exposed to GABAergic modulation in an opposite manner.

  5. Midbrain dopamine neurons bidirectionally regulate CA3-CA1 synaptic drive.

    Science.gov (United States)

    Rosen, Zev B; Cheung, Stephanie; Siegelbaum, Steven A

    2015-12-01

    Dopamine (DA) is required for hippocampal-dependent memory and long-term potentiation (LTP) at CA1 Schaffer collateral (SC) synapses. It is therefore surprising that exogenously applied DA has little effect on SC synapses, but suppresses CA1 perforant path (PP) inputs. To examine DA actions under more physiological conditions, we used optogenetics to release DA from ventral tegmental area inputs to hippocampus. Unlike exogenous DA application, optogenetic release of DA caused a bidirectional, activity-dependent modulation of SC synapses, with no effect on PP inputs. Low levels of DA release, simulating tonic DA neuron firing, depressed the SC response through a D4 receptor-dependent enhancement of feedforward inhibition mediated by parvalbumin-expressing interneurons. Higher levels of DA release, simulating phasic firing, increased SC responses through a D1 receptor-dependent enhancement of excitatory transmission. Thus, tonic-phasic transitions in DA neuron firing in response to motivational demands may cause a modulatory switch from inhibition to enhancement of hippocampal information flow.

  6. Perforating pilomatricoma.

    Science.gov (United States)

    Zulaica, A; Peteiro, C; Quintas, C; Pereiro, M; Toribio, J

    1988-12-01

    A case of perforating pilomatricoma is described. A few published cases have shared the following features: rapid development, reddish exophytic clinical appearance with surface alterations suggestive of perforation, relatively shallow location making contact with the epidermis, and the occurrence of transepithelial elimination phenomena.

  7. Septo-hippocampal deafferentation protects CA1 neurons against ischemic injury.

    Science.gov (United States)

    Buchan, A M; Pulsinelli, W A

    1990-03-26

    Excessive synaptic excitation caused by transient cerebral ischemia has been proposed to explain the greater vulnerability of specific neuronal populations to ischemic injury. We tested this hypothesis in rats by cutting, alone or in combination, the afferent fibers that travel in the fimbria/fornix, the perforant, or the Schäffer collateral pathways and innervate the right CA1 hippocampus. Seven to twelve days later the animals were subjected to 30 min of reversible forebrain ischemia. Irreversible damage to the CA1 neurons was assessed with the light microscope after 70-120 h of cerebral reperfusion. The left, unlesioned hippocampus served as a control. Simultaneous cutting of the 3 major afferent pathways significantly reduced CA1 neuronal damage compared to the unlesioned side (P less than 0.001) or to sham-lesioned controls (P less than 0.001). Selective lesions of the fimbria/fornix but not the perforant or the Schäffer collateral pathways also protected against ischemic CA1 damage. These data indicate that afferent fiber input modulates hippocampal damage caused by ischemia, but they are inconsistent with the hypothesis that excitatory afferent fibers, travelling in either the perforant or the Schäffer collateral pathways alone, play a major role. Neurotransmitters, other than those activating excitatory amino acid receptors or yet-to-be-identified synaptic events, may be invoked to explain the spatial and temporal sensitivity of hippocampal CA1 neurons to ischemia.

  8. Long-term fluoxetine treatment induces input-specific LTP and LTD impairment and structural plasticity in the CA1 hippocampal subfield.

    Science.gov (United States)

    Rubio, Francisco J; Ampuero, Estíbaliz; Sandoval, Rodrigo; Toledo, Jorge; Pancetti, Floria; Wyneken, Ursula

    2013-01-01

    Antidepressant drugs are usually administered for several weeks for the treatment of major depressive disorder. However, they are also prescribed in several additional psychiatric conditions as well as during long-term maintenance treatments. Antidepressants induce adaptive changes in several forebrain structures which include modifications at glutamatergic synapses. We recently found that repetitive administration of the selective serotonin reuptake inhibitor (SSRI) fluoxetine to naïve adult male rats induced an increase of mature, mushroom-type dendritic spines in several forebrain regions. This was associated with an increase of GluA2-containing α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptors (AMPA-Rs) in telencephalic postsynaptic densities. To unravel the functional significance of such a synaptic re-arrangement, we focused on glutamate neurotransmission in the hippocampus. We evaluated the effect of four weeks of 0.7 mg/kg fluoxetine on long-term potentiation (LTP) and long-term depression (LTD) in the CA1 hippocampal subfield. Recordings in hippocampal slices revealed profound deficits in LTP and LTD at Schaffer collateral-CA1 synapses associated to increased spine density and enhanced presence of mushroom-type spines, as revealed by Golgi staining. However, the same treatment had neither an effect on spine morphology, nor on LTP and LTD at perforant path-CA1 synapses. Cobalt staining and immunohistochemical experiments revealed decreased AMPA-R Ca(2+) permeability in the stratum radiatum (s.r.) together with increased GluA2-containing Ca(2+) impermeable AMPA-Rs. Therefore, 4 weeks of fluoxetine treatment promoted structural and functional adaptations in CA1 neurons in a pathway-specific manner that were selectively associated with impairment of activity-dependent plasticity at Schaffer collateral-CA1 synapses.

  9. Interlamellar CA1 network in the hippocampus

    OpenAIRE

    Yang, Sunggu; Yang, Sungchil; Moreira, Thais; Hoffman, Gloria; Carlson, Greg C.; Bender, Kevin J.; Alger, Bradley E.; Tang, Cha-Min

    2014-01-01

    It has generally been thought that CA1 cells form only negligible connections with each other along the longitudinal axis of the hippocampus. But if CA1 cells were interconnected in an effective autoassociational network, this information would add a critical new dimension to our understanding of cellular processing within this structure. Here, we report the existence of a well-organized, longitudinally projecting synaptic network among CA1 pyramidal neurons. We further show that synapses of ...

  10. Spontaneous external gallbladder perforation

    Energy Technology Data Exchange (ETDEWEB)

    Noeldge, G.; Wimmer, B.; Kirchner, R.

    1981-04-01

    Spontaneous perforation of the gallbladder is one complication of cholelithiasis. There is a greater occurence of free perforation in the peritoneal cavity with bilary pertonitis, followed by the perforation into the stomach, small intestine and colon. A single case of the nowadays rare spontaneous perforation in and through the abdominal wall will be reported. Spontaneous gallbladder perforation appears nearly asymptomatic in its clinical course because of absent biliary peritonitis.

  11. Reactive perforating collagenosis

    Directory of Open Access Journals (Sweden)

    Yadav Mukesh

    2009-01-01

    Full Text Available Reactive perforating collagenosis is a rare cutaneous disorder of unknown etiology. We hereby describe a case of acquired reactive perforating collagenosis in a patient of diabetes and chronic renal failure.

  12. Hippocampal CA1 Ripples as Inhibitory Transients.

    Directory of Open Access Journals (Sweden)

    Paola Malerba

    2016-04-01

    Full Text Available Memories are stored and consolidated as a result of a dialogue between the hippocampus and cortex during sleep. Neurons active during behavior reactivate in both structures during sleep, in conjunction with characteristic brain oscillations that may form the neural substrate of memory consolidation. In the hippocampus, replay occurs within sharp wave-ripples: short bouts of high-frequency activity in area CA1 caused by excitatory activation from area CA3. In this work, we develop a computational model of ripple generation, motivated by in vivo rat data showing that ripples have a broad frequency distribution, exponential inter-arrival times and yet highly non-variable durations. Our study predicts that ripples are not persistent oscillations but result from a transient network behavior, induced by input from CA3, in which the high frequency synchronous firing of perisomatic interneurons does not depend on the time scale of synaptic inhibition. We found that noise-induced loss of synchrony among CA1 interneurons dynamically constrains individual ripple duration. Our study proposes a novel mechanism of hippocampal ripple generation consistent with a broad range of experimental data, and highlights the role of noise in regulating the duration of input-driven oscillatory spiking in an inhibitory network.

  13. Hippocampal CA1 Ripples as Inhibitory Transients.

    Science.gov (United States)

    Malerba, Paola; Krishnan, Giri P; Fellous, Jean-Marc; Bazhenov, Maxim

    2016-04-01

    Memories are stored and consolidated as a result of a dialogue between the hippocampus and cortex during sleep. Neurons active during behavior reactivate in both structures during sleep, in conjunction with characteristic brain oscillations that may form the neural substrate of memory consolidation. In the hippocampus, replay occurs within sharp wave-ripples: short bouts of high-frequency activity in area CA1 caused by excitatory activation from area CA3. In this work, we develop a computational model of ripple generation, motivated by in vivo rat data showing that ripples have a broad frequency distribution, exponential inter-arrival times and yet highly non-variable durations. Our study predicts that ripples are not persistent oscillations but result from a transient network behavior, induced by input from CA3, in which the high frequency synchronous firing of perisomatic interneurons does not depend on the time scale of synaptic inhibition. We found that noise-induced loss of synchrony among CA1 interneurons dynamically constrains individual ripple duration. Our study proposes a novel mechanism of hippocampal ripple generation consistent with a broad range of experimental data, and highlights the role of noise in regulating the duration of input-driven oscillatory spiking in an inhibitory network.

  14. Strategies in Perforated Diverticulitis

    NARCIS (Netherlands)

    J. Vermeulen (Jefrey)

    2010-01-01

    textabstractAlthough diverticulitis is a common disease affecting the gastrointestinal tract, few is known about the optimal surgical treatment of its most severe form: perforated diverticulitis. Regardless of the selected operation, perforated diverticulitis is associated with mortality rates up to

  15. Pedicled perforator flaps

    DEFF Research Database (Denmark)

    Demirtas, Yener; Ozturk, Nuray; Kelahmetoglu, Osman;

    2009-01-01

    Described in this study is a surgical concept that supports the "consider and use a pedicled perforator flap whenever possible and indicated" approach to reconstruct a particular skin defect. The operation is entirely free-style; the only principle is to obtain a pedicled perforator flap to recon......Described in this study is a surgical concept that supports the "consider and use a pedicled perforator flap whenever possible and indicated" approach to reconstruct a particular skin defect. The operation is entirely free-style; the only principle is to obtain a pedicled perforator flap...... more practical and creative to use a free-style manner during pedicled perforator flap surgery, instead of being obliged to predefined templates for this type of procedure....

  16. Selective shunting of the NMDA EPSP component by the slow afterhyperpolarization in rat CA1 pyramidal neurons.

    Science.gov (United States)

    Fernández de Sevilla, David; Fuenzalida, Marco; Porto Pazos, Ana B; Buño, Washington

    2007-05-01

    Pyramidal neuron dendrites express voltage-gated conductances that control synaptic integration and plasticity, but the contribution of the Ca(2+)-activated K(+)-mediated currents to dendritic function is not well understood. Using dendritic and somatic recordings in rat hippocampal CA1 pyramidal neurons in vitro, we analyzed the changes induced by the slow Ca(2+)-activated K(+)-mediated afterhyperpolarization (sAHP) generated by bursts of action potentials on excitatory postsynaptic potentials (EPSPs) evoked at the apical dendrites by perforant path-Schaffer collateral stimulation. Both the amplitude and decay time constants of EPSPs (tau(EPSP)) were reduced by the sAHP in somatic recordings. In contrast, the dendritic EPSP amplitude remained unchanged, whereas tau(EPSP) was reduced. Temporal summation was reduced and spatial summation linearized by the sAHP. The amplitude of the isolated N-methyl-D-aspartate component of EPSPs (EPSP(NMDA)) was reduced, whereas tau(NMDA) was unaffected by the sAHP. In contrast, the sAHP did not modify the amplitude of the isolated EPSP(AMPA) but reduced tau(AMPA) both in dendritic and somatic recordings. These changes are attributable to a conductance increase that acted mainly via a selective "shunt" of EPSP(NMDA) because they were absent under voltage clamp, not present with imposed hyperpolarization simulating the sAHP, missing when the sAHP was inhibited with isoproterenol, and reduced under block of EPSP(NMDA). EPSPs generated at the basal dendrites were similarly modified by the sAHP, suggesting both a somatic and apical dendritic location of the sAHP channels. Therefore the sAHP may play a decisive role in the dendrites by regulating synaptic efficacy and temporal and spatial summation.

  17. REDUCTION OF ADENOSINE-A1-RECEPTORS IN THE PERFORANT PATHWAY TERMINAL ZONE IN ALZHEIMER HIPPOCAMPUS

    NARCIS (Netherlands)

    JAARSMA, D; SEBENS, JB; KORF, J

    1991-01-01

    The cells of origin of the perforant pathway are destroyed in Alzheimer's disease (AD). In rat the adenosine A1-receptors are specifically localized on the perforant path terminals in the molecular layer of the dentate gyrus. In the present study the density of A1-receptors in the hippocampus of Alz

  18. Spontaneous Perforation of Pyometra.

    Science.gov (United States)

    Sharma, Nalini; Singh, Ahanthem Santa; Bhaphiralyne, Wankhar

    2016-04-01

    Pyometra is collection of purulent material which occurs when there is interference with its normal drainage. It is an uncommon condition with incidence of 0.1 to 0.5% of all gynecological patients. Spontaneous rupture of uterus is an extremely rare complication of pyometra. A 65-year-old lady presented with pain abdomen and purulent vaginal discharge. Preoperative diagnosis of pyometra was made by magnetic resonance imaging (MRI). Laparotomy followed by peritoneal lavage and repair of perforation was performed. Although spontaneously perforated pyometra is rare, the condition must be borne in mind with regard to elderly women with acute abdominal pain. Preoperative diagnosis of perforated pyometra is absolutely essential. Computed tomography (CT) and MRI are diagnostic tools. In selected cases conservative approach at surgery can be opted.

  19. Perforated peptic ulcer

    DEFF Research Database (Denmark)

    Søreide, Kjetil; Thorsen, Kenneth; Harrison, Ewen M

    2015-01-01

    Perforated peptic ulcer is a common emergency condition worldwide, with associated mortality rates of up to 30%. A scarcity of high-quality studies about the condition limits the knowledge base for clinical decision making, but a few published randomised trials are available. Although Helicobacte...

  20. Topological organization of CA3-to-CA1 excitation.

    Science.gov (United States)

    Hongo, Yoshie; Ogawa, Koichi; Takahara, Yuji; Takasu, Keiko; Royer, Sebastien; Hasegawa, Minoru; Sakaguchi, Gaku; Ikegaya, Yuji

    2015-09-01

    The CA1-projecting axons of CA3 pyramidal cells, called Schaffer collaterals, constitute one of the major information flow routes in the hippocampal formation. Recent anatomical studies have revealed the non-random structural connectivity between CA3 and CA1, but little is known regarding the functional connectivity (i.e. how CA3 network activity is functionally transmitted downstream to the CA1 network). Using functional multi-neuron calcium imaging of rat hippocampal slices, we monitored the spatiotemporal patterns of spontaneous CA3 and CA1 burst activity under pharmacological GABAergic blockade. We found that spatially clustered CA3 activity patterns were transformed into layered CA1 activity sequences. Specifically, synchronized bursts initiated from multiple hot spots in CA3 ensembles, and CA1 neurons located deeper in the pyramidal cell layer were recruited during earlier phases of the burst events. The order of these sequential activations was maintained across the bursts, but the sequence velocity varied depending on the inter-burst intervals. Thus, CA3 axons innervate CA1 neurons in a highly topographical fashion.

  1. The Versatile Modiolus Perforator Flap

    DEFF Research Database (Denmark)

    Gunnarsson, Gudjon Leifur; Thomsen, Jorn Bo

    2016-01-01

    BACKGROUND: Perforator flaps are well established, and their usefulness as freestyle island flaps is recognized. The whereabouts of vascular perforators and classification of perforator flaps in the face are a debated subject, despite several anatomical studies showing similar consistency. In our....... The color Doppler ultrasonography study detected a sizeable perforator at the level of the modiolus lateral to the angle of the mouth within a radius of 1 cm. This confirms the anatomical findings of previous authors and indicates that the modiolus perforator is a consistent anatomical finding, and flaps...

  2. Inhibitory Gating of Input Comparison in the CA1 Microcircuit.

    Science.gov (United States)

    Milstein, Aaron D; Bloss, Erik B; Apostolides, Pierre F; Vaidya, Sachin P; Dilly, Geoffrey A; Zemelman, Boris V; Magee, Jeffrey C

    2015-09-23

    Spatial and temporal features of synaptic inputs engage integration mechanisms on multiple scales, including presynaptic release sites, postsynaptic dendrites, and networks of inhibitory interneurons. Here we investigate how these mechanisms cooperate to filter synaptic input in hippocampal area CA1. Dendritic recordings from CA1 pyramidal neurons reveal that proximal inputs from CA3 as well as distal inputs from entorhinal cortex layer III (ECIII) sum sublinearly or linearly at low firing rates due to feedforward inhibition, but sum supralinearly at high firing rates due to synaptic facilitation, producing a high-pass filter. However, during ECIII and CA3 input comparison, supralinear dendritic integration is dynamically balanced by feedforward and feedback inhibition, resulting in suppression of dendritic complex spiking. We find that a particular subpopulation of CA1 interneurons expressing neuropeptide Y (NPY) contributes prominently to this dynamic filter by integrating both ECIII and CA3 input pathways and potently inhibiting CA1 pyramidal neuron dendrites.

  3. Spontaneous Perforation of Pyometra

    OpenAIRE

    Sharma, Nalini; Singh, Ahanthem Santa; Bhaphiralyne, Wankhar

    2016-01-01

    Pyometra is collection of purulent material which occurs when there is interference with its normal drainage. It is an uncommon condition with incidence of 0.1 to 0.5% of all gynecological patients. Spontaneous rupture of uterus is an extremely rare complication of pyometra. A 65-year-old lady presented with pain abdomen and purulent vaginal discharge. Preoperative diagnosis of pyometra was made by magnetic resonance imaging (MRI). Laparotomy followed by peritoneal lavage and repair of perfor...

  4. Gastric conduit perforation.

    Science.gov (United States)

    Patil, Nilesh; Kaushal, Arvind; Jain, Amit; Saluja, Sundeep Singh; Mishra, Pramod Kumar

    2014-08-16

    As patients with carcinoma of the esophagus live longer, complications associated with the use of a gastric conduit are increasing. Ulcers form in the gastric conduit in 6.6% to 19.4% of patients. There are a few reports of perforation of a gastric conduit in the English literature. Almost all of these were associated with serious complications. We report a patient who developed a tension pneumothorax consequent to spontaneous perforation of an ulcer in the gastric conduit 7 years after the index surgery in a patient with carcinoma of the gastroesophageal junction. He responded well to conservative management. Complications related to a gastric conduit can be because of multiple factors. Periodic endoscopic surveillance of gastric conduits should be considered as these are at a higher risk of ulcer formation than a normal stomach. Long term treatment with proton pump inhibitors may decrease complications. There are no guidelines for the treatment of a perforated gastric conduit ulcer and the management should be individualized.

  5. Duodenal perforation in childhood dermatomyositis

    Energy Technology Data Exchange (ETDEWEB)

    Magill, H.L.; Hixson, S.D.; Whitington, G.; Igarashi, M.; Hannissian, A.

    1984-01-01

    Perforation of the duodenum is an uncommon, but serious complication which may occur in children with dermatomyositis. In this disease vasculitis may involve the bowel to a variable extent and result in radiologic manifestations of intestinal injury ranging from benign pneumatosis intestinalis to signs of bowel perforation. We report two children with dermatomyositis in whom perforation of the second portion of the duodenum occurred. This serious complication should be considered in any child with dermatomyositis when extraluminal gas is suspected on abdominal radiographs.

  6. Physiological and morphological diversity of immunocytochemically defined parvalbumin- and cholecystokinin-positive interneurones in CA1 of the adult rat hippocampus.

    Science.gov (United States)

    Pawelzik, Hannelore; Hughes, David I; Thomson, Alex M

    2002-02-18

    To investigate the electrophysiological properties, synaptic connections, and anatomy of individual parvalbumin-immunoreactive (PV-IR) and cholecystokinin-immunoreactive (CCK-IR) interneurones in CA1, dual intracellular recordings using biocytin-filled microelectrodes in slices of adult rat hippocampus were combined with fluorescence labelling of PV- and CCK-containing cells. Of 36 PV-IR cells, 29 were basket cells, with most of their axonal arbours in the stratum pyramidale (SP). Six were bistratified cells with axons ramifying throughout stratum oriens (SO) and stratum radiatum (SR). One was a putative axo-axonic cell with an axonal arbour confined to half of the SP and a narrow adjacent region of the SO. Of 27 CCK-IR neurones, 13 were basket cells, with most of their axonal arbours in the SP, and included basket cells with somata in the SP (6), SO (3), and SR (2) and at the border between the stratum lacunosum-moleculare (SLM) and the SR (2). In addition, several dendrite-targeting cell classes expressed CCK-IR: 4 of 9 bistratified cells with axons ramifying in the SO and SR; all five Schaffer-associated cells whose axons ramified extensively in the SR; both cells classified as quadrilaminar because their axons ramified in the SO, SP, SR, and SLM; one SO-SO cell whose dendritic and axonal arbours were contained within the SO; and one perforant path-associated cell with axonal and dendritic arbours within the distal SR and SLM. The majority (31 of 36) of PV-IR neurones recorded were fast-spiking, and most fast-spiking cells tested (25 of 29 basket, 1 axo-axonic, and 5 of 6 bistratified cells) were PV-IR. However, 1 of 6 regular-spiking basket, 1 of 4 regular-spiking bistratified, and 3 of 5 burst-firing basket cells were also PV-IR. In contrast, the majority (17 of 27) of the CCK-IR neurones recorded were regular-spiking, 3 were burst-firing, and 7 were fast-spiking. These data confirm that the majority of PV-IR and CCK-IR axon terminals innervate proximal

  7. Perforating disorders of the skin

    Directory of Open Access Journals (Sweden)

    Kalpana Arora

    2013-01-01

    Full Text Available Background: Perforating disorders of the skin, is an often overlooked entity characterized by transepidermal elimination of material from the upper dermis and are classified histopathologically according to the type of epidermal disruption and the nature of the eliminated material. They include Kyrle′s disease, perforating folliculitis, reactive perforating collagenosis, and elastosis perforans serpiginosa. Aim: The aim of this study was to delineate the clinical and histopathological features of perforating disorders of the skin. Materials and Methods: In our study, we reviewed last 2 years skin biopsies received by us. Hematoxylin and eosin sections were re-examined and histochemical stainings (elastic van Gieson and Masson trichrome stains were also used for histopathological evaluation. Results: We reviewed five cases of perforating disorders of skin which included two cases of Kyrle′s disease, two cases of reactive perforating collagenosis and a single case of perforating folliculitis. Two patients had family history of perforating dermatosis in their siblings and three had associated systemic disease. Conclusion: Perforating disorders of the skin should be considered when ulcer with keratotic plugs is found.

  8. [Perforating necrobiosis lipoidica].

    Science.gov (United States)

    Peteiro, C; Zulaica, A; Toribio, J

    1986-01-01

    This is the case history of a woman with a 6 year history of insulin-dependent diabetes mellitus and a 5 year history of tuberous lesions on the dorsal aspect of the metacarpophalangeal joints. Histological examination revealed multiple necrobiotic foci throughout the dermis and subcutaneous tissue, with varying degrees of degeneration, alternating with fibrotic areas. This picture is compatible with lipoid necrobiosis. The existence of various foci of epithelial perforation, manifested clinically by a point hyperkeratosis similar in appearance to blackheads, suggests transfollicular elimination. This would explain the total absence of a pilosebaceous follicles in the lesion.

  9. Spontaneous Perforation of Pyometra

    Directory of Open Access Journals (Sweden)

    Begüm Yildizhan

    2006-01-01

    Full Text Available Pyometra is the accumulation of purulent material in the uterine cavity. Its reported incidence is 0.01–0.5% in gynecologic patients; however, as far as elderly patients are concerned, its incidence is 13.6% [3]. The most common cause of pyometra is malignant diseases of genital tract and the consequences of their treatment (radiotherapy. Other causes are benign tumors like leiomyoma, endometrial polyps, senile cervicitis, cervical occlusion after surgery, puerperal infections, and congenital cervical anomalies. Spontaneous rupture of the uterus is an extremely rare complication of pyometra. To our knowledge, only 21 cases of spontaneous perforation of pyometra have been reported in English literature since 1980. This paper reports an additional case of spontaneous uterine rupture.

  10. Familial reactive perforating collagenosis

    Directory of Open Access Journals (Sweden)

    Bhat Yasmeen

    2009-01-01

    Full Text Available Background: Reactive perforating collagenosis (RPC is one of the rare forms of transepidermal elimination in which genetically altered collagen is extruded from the epidermis. This disease usually starts in early childhood as asymptomatic umbilicated papules on extremities, and the lesions become more conspicuous with age. Aims: The objective of our study was to determine the clinico-pathological features of RPC and the response to various treatment modalities. Methods: Ten patients of RPC, belonging to five different families, were studied clinically. Various laboratory investigations were carried out and diagnosis was made by histopathology of the lesions. Patients were given various topical and oral treatments. Results: RPC is familial in most cases without any definite inheritance pattern. It begins in childhood and the lesions are usually recurrent and become profuse and large with age. Systemic diseases have no role in the onset of lesions. Conclusion: Oral and topical retinoids in combination with emollients is the best treatment option.

  11. Rett syndrome and gastric perforation.

    Science.gov (United States)

    Shah, Malay B; Bittner, James G; Edwards, Michael A

    2008-04-01

    Rett Syndrome is associated with decreased peristaltic esophageal waves and gastric dysmotility, resulting in swallowing difficulties and gastric dilation. Rarely, gastric necrosis and perforation occur. Our case represents the third reported case of gastric necrosis and perforation associated with Rett Syndrome. A 31-year-old female after 11 hours of intermittent emesis and constant, sharp abdominal pain presented with evidence of multiorgan system failure including hypovolemic shock, metabolic acidosis, coagulopathy, and hepatorenal failure. A chest radiograph revealed intra-abdominal free air necessitating emergent laparotomy. During exploration, a severely dilated, thin-walled stomach with an area of necrosis and gross perforation was noted. Wedge resection of the necrotic tissue and primary closure were performed. Despite aggressive perioperative resuscitation and ventilation support, the patient died 3 hours postoperatively secondary to refractory shock and hypoxemia. Severe gastric dilation can occur with Rett Syndrome and may cause gastric necrosis and perforation. Prolonged elevated gastric pressures can decrease perfusion and may contribute to perforation. Timely decompression via percutaneous endoscopic or surgical gastrostomy could decrease the risk of perforation particularly when significant gastric distention is present. Consideration of gastric necrosis and perforation in patients with Rett Syndrome may lead to earlier intervention and decreased mortality.

  12. Perforated midgut diverticulitis: Revisited

    Institute of Scientific and Technical Information of China (English)

    Milan Spasojevic; Jens Marius Naesgaard; Dejan Ignjatovic

    2012-01-01

    AIM:To study and provide data on the evolution of medical procedures and outcomes of patients suffering from perforated midgut diverticulitis.METHODS:Three data sources were used:the Medline and Google search engines were searched for case reports on one or more patients treated for perforated midgut diverticulitis (Meckel's diverticulitis excluded)that were published after 1995.The inclusion criterion was sufficient individual patient data in the article.Both indexed and non-indexed journals were used.Patients treated for perforated midgut diverticulitis at Vestfold Hospital were included in this group.Data on symptoms,laboratory and radiology results,treatment modalities,surgical access,procedures,complications and outcomes were collected.The Norwegian patient registry was searched to find patients operated upon for midgut diverticulitis from 1999 to 2007.The data collected were age,sex,mode of access,surgical procedure performed and number of patients per year.Historical controls were retrieved from an article published in 1995 containing pertinent individual patient data.Statistical analysis was done with SPSS software.RESULTS:Group I:106 patients (48 men) were found.Mean age was 72.2 ± 13.1 years (mean ± SD).Age or sex had no impact on outcomes (P =0.057 and P =0.771,respectively).Preoperative assessment was plain radiography in 53.3% or computed tomography (CT)in 76.1%.Correct diagnosis was made in 77.1% with CT,5.6% without (P =0.001).Duration of symptoms before hospitalization was 3.6 d (range:1-35 d),but longer duration was not associated with poor outcome (P =0.748).Eighty-six point eight percent of patients underwent surgery,92.4% of these through open access where 90.1% had bowel resection.Complications occurred in 19.2% of patients and 16.3% underwent reoperation.Distance from perforation to Treitz ligament was 41.7 ± 28.1 cm.At surgery,no peritonitis was found in 29.7% of patients,local peritonitis in 47.5%,and diffuse

  13. Unusual presentation of gallbladder perforation

    OpenAIRE

    Jayasinghe, G.; Adam, J.; Abdul-Aal, Y.

    2016-01-01

    Introduction: Gall bladder perforation is associated with high mortality rates and therefore must be recognised and managed promptly. We present an unusual presentation of spontaneous gall bladder perforation. Case presentation: An elderly lady with multiple medical co-morbidities was admitted with sepsis following a fall. Initial assessment lead to a diagnosis of pneumonia, however a rapidly expanding right flank mass was incidentally noted during routine nursing care. Imaging studies wer...

  14. Helicobacter pylori in gastroduodenal perforation

    Directory of Open Access Journals (Sweden)

    Bharat B Dogra

    2014-01-01

    Full Text Available Background:peptic ulcers were earlier believed to be caused by dietary factors, gastric acid, and stress. However, in 1983, Warren and Marshall identified the correlation between Helicobacter pylori (H. pylori and peptic ulcers. It is now well established that most of the peptic ulcers occur as a result of H. pylori infection. But the co-relation between perforated peptic ulcer and H. pylori infection is not yet fully established. Aims and objectives : to study the prevalence of H. pylori infection in patients with perforated peptic ulcer. Materials and methods: this was a prospective study carried out in all cases of perforated peptic ulcer reporting in surgical wards of a medical college during 2008-2010. A total of 50 cases, presenting as acute perforation of duodenum and stomach during this period, formed the study group. After resuscitation, all the cases were subjected to emergency exploratory laparotomy. The exact site of perforation was identified, biopsy was taken from the ulcer margin from 2-3 sites and the tissue was sent for H. pylori culture and histopathological examination. Simple closure of perforation, omentoplasty, thorough peritoneal lavage and drainage was carried out. Results: out of the 50 cases of perforated peptic ulcer, 38 happened to be males, and only 12 were females. The age of the patients ranged from 20 to 70 years. All the patients underwent only emergency laparotomy. As many as 46 cases (92% turned out to be positive for H. pylori and only four cases (8% were negative for this infection. Postoperatively, patients who were found to be positive for H. pylori were put on anti-H. pylori treatment. Conclusion: there was a high prevalence of H. pylori infection in patients with perforated gastroduodenal ulcers.

  15. Spontaneous Perforation of Rectosigmoid Colon

    Directory of Open Access Journals (Sweden)

    Farhad Haj Sheikholeslami

    2010-12-01

    Full Text Available Spontaneous perforation of the sigmoid colon or rectom is definedas a sudden perforation of the colon in the absence of diseasessuch as tumors, diverticulosis or external injury. It is avery rare finding, and if neglected, results in severe peritonitisand high mortality. The causes of this rare condition are numerous,and in this case it might be due to the chronic constipationinduced by an anticholinergic antipsychotic.Iran J Med Sci 2010; 35(4: 339-341.

  16. Hippocampal CA1 interneurons: an in vivo intracellular labeling study.

    Science.gov (United States)

    Sik, A; Penttonen, M; Ylinen, A; Buzsáki, G

    1995-10-01

    Fast spiking interneurons in the CA1 area of the dorsal hippocampus were recorded from and filled with biocytin in anesthetized rats. The full extent of their dendrites and axonal arborizations as well as their calcium binding protein content were examined. Based on the spatial extent of axon collaterals, local circuit cells (basket and O-LM neurons) and long-range cells (bistratified, trilaminar, and backprojection neurons) could be distinguished. Basket cells were immunoreactive for parvalbumin and their axon collaterals were confined to the pyramidal layer. A single basket cell contacted more than 1500 pyramidal neurons and 60 other parvalbumin-positive interneurons. Commissural stimulation directly discharged basket cells, followed by an early and late IPSPs, indicating interneuronal inhibition of basket cells. The dendrites of another local circuit neuron (O-LM) were confined to stratum oriens and it had a small but high-density axonal terminal field in stratum lacunosum-moleculare. The fastest firing cell of all interneurons was a calbindin-immunoreactive bistratified neuron with axonal targets in stratum oriens and radiatum. Two neurons with their cell bodies in the alveus innervated the CA3 region (backprojection cells), in addition to rich axon collaterals in the CA1 region. The trilaminar interneuron had axon collaterals in strata radiatum, oriens and pyramidale with its dendrites confined to stratum oriens. Commissural stimulation evoked an early EPSP-IPSP-late depolarizing potential sequence in this cell. All interneurons formed symmetric synapses with their targets at the electron microscopic level. These findings indicate that interneurons with distinct axonal targets have differential functions in shaping the physiological patterns of the CA1 network.

  17. CLINICAL STUDY OF DUODENAL PERFORATION

    Directory of Open Access Journals (Sweden)

    Sambasiva Rao

    2016-04-01

    Full Text Available BACKGROUND The duodenal injury can pose a formidable challenge to the surgeon and failure to manage it properly may have devastating results. Over the centuries, there was little to offer the patient of acute abdomen beyond cupping, purgation and enemas, all of which did more harm than good. It was not until 1884 that Mikulicz made an attempt to repair a perforation. Recent statistics indicate roughly 10% of population develop gastric or duodenal ulcer in life time. Roughly 1-3% of population above the age of 20 years have some degree of peptic ulcer activity during any annual period. A detailed history with regards to the signs and symptoms of the patient, a meticulous examination, radiological and biochemical investigations help to arrive at a correct preoperative diagnosis. In this study, a sincere effort has been put to understand the demographic patterns, to understand the underlying aetiology and to understand the effectiveness of the standard methods of investigation and treatment in use today. METHODS This is a 24 months prospective study i.e., from September 2011 to September 2013 carried out at Dr. Pinnamaneni Siddhartha Institute of Medical Sciences & Research Foundation. The study included the patients presenting to Dr. Pinnamaneni Siddhartha Institute of Medical Sciences & Research Foundation to emergency ward with signs and symptoms of hollow viscus perforation. The sample size included 30 cases of duodenal perforation. RESULTS Duodenal ulcer perforation commonly occurs in the age group of 30-60 years, but it can occur in any age group. Majority of the patients were male. Smoking and alcohol consumption were risk factors in most cases (53.3% for the causation of duodenal ulcer perforation. Sudden onset of abdominal pain, situated at epigastrium and right hypochondrium was a constant symptom (100%. Vomiting, constipation and fever were not so common. CONCLUSION The emergency surgical management for perforated duodenal ulcer is by

  18. Posterior repair with perforated porcine dermal graft

    Directory of Open Access Journals (Sweden)

    G. Bernard Taylor

    2008-02-01

    Full Text Available OBJECTIVE: To compare postoperative vaginal incision separation and healing in patients undergoing posterior repair with perforated porcine dermal grafts with those that received grafts without perforations. Secondarily, the tensile properties of the perforated and non-perforated grafts were measured and compared. MATERIALS AND METHODS: This was a non-randomized retrospective cohort analysis of women with stage II or greater rectoceles who underwent posterior repair with perforated and non-perforated porcine dermal grafts (PelvicolTM CR Bard Covington, GA USA. The incidence of postoperative vaginal incision separation (dehiscence was compared. A secondary analysis to assess graft tensile strength, suture pull out strength, and flexibility after perforation was performed using standard test method TM 0133 and ASTM bending and resistance protocols. RESULTS: Seventeen percent of patients (21/127 who received grafts without perforations developed vaginal incision dehiscence compared to 7% (5/71 of patients who received perforated grafts (p = 0.078. Four patients with vaginal incision dehiscence with non-perforated grafts required surgical revision to facilitate healing. Neither tensile strength or suture pull out strength were significantly different between perforated and non-perforated grafts (p = 0.81, p = 0.29, respectively. There was no difference in the flexibility of the two grafts (p = 0.20. CONCLUSION: Perforated porcine dermal grafts retain their tensile properties and are associated with fewer vaginal incision dehiscences.

  19. Perforating Disseminated Necrobiosis Lipoidica Diabeticorum

    Directory of Open Access Journals (Sweden)

    Paula Lozanova

    2013-01-01

    Full Text Available Perforating necrobiosis lipoidica is a very rare clinical variant which consists of degeneration and transepidermal elimination of the collagen with few cases reported in the literature. In two-thirds of the patients it associates with diabetes, with no relation with the glucose control. We present a 42-year-old female patient with a 7-year history of diabetes on insulin therapy, referred to our clinic with a 3-year history of multiple asymptomatic firm plaques disseminated on the upper and lower extremities. The clinical and histological findings proved the diagnosis of perforating necrobiosis lipoidica.

  20. Triple gastric peptic ulcer perforation.

    Science.gov (United States)

    Radojkovic, Milan; Mihajlovic, Suncica; Stojanovic, Miroslav; Stanojevic, Goran; Damnjanovic, Zoran

    2016-03-01

    Patients with advanced or metastatic cancer have compromised nutritional, metabolic, and immune conditions. Nevertheless, little is known about gastroduodenal perforation in cancer patients. Described in the present report is the case of a 41-year old woman with stage IV recurrent laryngeal cancer, who used homeopathic anticancer therapy and who had triple peptic ulcer perforation (PUP) that required surgical repair. Triple gastric PUP is a rare complication. Self-administration of homeopathic anticancer medication should be strongly discouraged when evidence-based data regarding efficacy and toxicity is lacking.

  1. Temporal organization of GABAergic interneurons in the intermediate CA1 hippocampus during network oscillations.

    Science.gov (United States)

    Forro, Thomas; Valenti, Ornella; Lasztoczi, Balint; Klausberger, Thomas

    2015-05-01

    Travelling theta oscillations and sharp wave-associated ripples (SWRs) provide temporal structures to neural activity in the CA1 hippocampus. The contribution of rhythm-generating GABAergic interneurons to network timing across the septotemporal CA1 axis remains unknown. We recorded the spike-timing of identified parvalbumin (PV)-expressing basket, axo-axonic, oriens-lacunosum moleculare (O-LM) interneurons, and pyramidal cells in the intermediate CA1 (iCA1) of anesthetized rats in relation to simultaneously detected network oscillations in iCA1 and dorsal CA1 (dCA1). Distinct interneuron types were coupled differentially to SWR, and the majority of iCA1 SWR events occurred simultaneously with dCA1 SWR events. In contrast, iCA1 theta oscillations were shifted in time relative to dCA1 theta oscillations. During theta cycles, the highest firing of iCA1 axo-axonic cells was followed by PV-expressing basket cells and subsequently by O-LM together with pyramidal cells, similar to the firing sequence of dCA1 cell types reported previously. However, we observed that this temporal organization of cell types is shifted in time between dCA1 and iCA1, together with the respective shift in theta oscillations. We show that GABAergic activity can be synchronized during SWR but is shifted in time from dCA1 to iCA1 during theta oscillations, highlighting the flexible inhibitory control of excitatory activity across a brain structure.

  2. Intestinal perforation--a unique cause.

    Science.gov (United States)

    Kansal, G; Agrawal, V

    2000-04-01

    An illiterate, 65 years old, male attended surgery emergency with features of perforation peritonitis. Exploratory laparotomy revealed perforation in the terminal ileum and a sharp metallic object pointing at the perforation site. This, on removal, was found to be the sharp edge of a blister pack (with intact tablet within). The perforation was repaired. The abdomen was closed after leaving a drain. Postoperatively the patient had a morbid period and ultimately responded to management.

  3. Hyperbilirubinemia as a predictor for appendiceal perforation

    DEFF Research Database (Denmark)

    Burcharth, J; Pommergaard, Hans-Christian; Rosenberg, J;

    2013-01-01

    Delayed or wrong diagnosis in patients with appendicitis can result in perforation and consequently increased morbidity and mortality. Serum bilirubin may be a useful marker for appendiceal perforation. The purpose of this systematic review was to evaluate studies investigating elevated serum...... bilirubin as a predictor for appendiceal perforation....

  4. Early Management Experience of Perforation after ERCP

    Directory of Open Access Journals (Sweden)

    Guohua Li

    2012-01-01

    Full Text Available Background and Aim. Perforation after endoscopic retrograde cholangiopancreatography (ERCP is a rare complication, but it is associated with significant mortality. This study evaluated the early management experience of these perforations. Patients and Methods. Between November 2003 and December 2011, a total of 8504 ERCPs were performed at our regional endoscopy center. Sixteen perforations (0.45% were identified and retrospectively reviewed. Results. Nine of these 16 patients with perforations were periampullary, 3 duodenal, 1 gastric fundus, and 3 patients had a perforation of an afferent limb of a Billroth II anastomosis. All patients with perforations were recognized during ERCP by X-ray and managed immediately. One patient with duodenal perforation and three patients with afferent limb perforation received surgery, others received medical conservative treatment which included suturing lesion, endoscopic nasobiliary drainage (ENBD, endoscopic retrograde pancreatic duct drainage (ERPD, gastrointestinal decompression, fasting, broad-spectrum antibiotics, and so on. All patients with perforation recovered successfully. Conclusions. We found that: (1 the diagnosis of perforation during ERCP may be easy, but you must pay attention to it. (2 Most retroperitoneal perforations can recover with only medical conservative treatment in early phase. (3 Most peritoneal perforations need surgery unless you can close the lesion up under endoscopy in early phase.

  5. Path Dependency

    OpenAIRE

    Mark Setterfield

    2015-01-01

    Path dependency is defined, and three different specific concepts of path dependency – cumulative causation, lock in, and hysteresis – are analyzed. The relationships between path dependency and equilibrium, and path dependency and fundamental uncertainty are also discussed. Finally, a typology of dynamical systems is developed to clarify these relationships.

  6. The freestyle pedicle perforator flap

    DEFF Research Database (Denmark)

    Gunnarsson, Gudjon Leifur; Jackson, Ian T; Westvik, Tormod S;

    2015-01-01

    not widely performed by the general plastic surgeons. The aim of this paper is to present the simplicity of pedicled perforator flap reconstruction of moderate-sized defects of the extremities and torso. METHODS: We retrospectively reviewed the charts of 34 patients reconstructed using 34 freestyle pedicled...

  7. Perforation due to ileocaecal salmonellosis

    NARCIS (Netherlands)

    Willemsen, PJ

    2002-01-01

    A 54-year old male patient was admitted with a tentative diagnosis of biliary pancreatitis. After 3 days, he developed an acute abdomen with a pneumoperitoneum. A laparotomy was performed : multiple perforations of the terminal ileum and a necrotic gallbladder were found. A right hemicolectomy with

  8. Perforated Peptic Ulcer: new insights

    NARCIS (Netherlands)

    M.J.O.E. Bertleff (Marietta)

    2011-01-01

    textabstractMuch has been written on perforated peptic ulcer (PPU) during the last hundred years. In 1500, when necropsies were first allowed, often a small hole was found in the anterior wall of the stomach, giving an explanation for symptoms of acute abdominal pain, nausea, vomiting which often le

  9. Unusual duodenal perforation following endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Martin Kobborg

    2011-02-01

    Full Text Available Perforation is a known but rare complication to Endoscopic retrograde cholangiopancreatography (ERCP with endoscopic sphincterotomy (ES. Most of the perforations are located in the periampullary area due to ES. This report presents an unusual perforation in the third part of the duodenum following ES. The patient an eigthy-sixt-year-old man underwent ERCP with ES. The patient had Magnetic Resonance Cholangio-pancreatography (MRCP and Computerized Tomography (CT verified cholelithiasis and intra- and extrahepatic cholestasis. The perforation was not found under the ERCP procedure but was clinically revealed when the patient developed pneumoscrotum after the procedure. A CT-scan with oral contrast later confirmed the duodenal perforation.

  10. Local-moment formation and metal–nonmetal transition in Ca1-YVO3 and Ca1-YTiO3

    Indian Academy of Sciences (India)

    Y Nishihara; H Kawanaka; H Bando

    2002-05-01

    Electron-doped metallic states of Ca1-YVO3 and Ca1-YTiO3 change into nonmetallic states around ∼ 0.4 and 0.6, respectively. The residual resistivity in the metallic states increases with increasing effective magnetic moment or coefficient of 2 term of resistivity. The effective moment reaches ∼ 0.5 B/molecule in Ca1-YVO3 and also in Ca1-YTiO3 near the metal–nonmetal phase boundary. In these metallic states, ∼ 10% of 3 atoms seem to have large localized magnetic moments. In electron-doped metallic sample of Ca1-YVO3, the temperature dependence of resistance shows no resistance-minimum. However, weak negative magneto-resistance is observed for the sample with = 0.2 up to 50 Tesla at 4.2 K.

  11. Reverse stochastic resonance in a hippocampal CA1 neuron model.

    Science.gov (United States)

    Durand, Dominique M; Kawaguchi, Minato; Mino, Hiroyuki

    2013-01-01

    Stochastic resonance (SR) is a ubiquitous and counter- intuitive phenomenon whereby the addition of noise to a non-linear system can improve the detection of sub-threshold signals. The "signal" is normally periodic or deterministic whereas the "noise" is normally stochastic. However, in neural systems, signals are often stochastic. Moreover, periodic signals are applied near neurons to control neural excitability (i.e. deep brain stimulation). We therefore tested the hypothesis that a quasi-periodic signal applied to a neural network could enhance the detection of a stochastic neural signal (reverse stochastic resonance). Using computational methods, a CA1 hippocampal neuron was simulated and a Poisson distributed subthreshold synaptic input ("signal") was applied to the synaptic terminals. A periodic or quasi periodic pulse train at various frequencies ("noise") was applied to an extracellular electrode located near the neuron. The mutual information and information transfer rate between the output and input of the neuron were calculated. The results display the signature of stochastic resonance with information transfer reaching a maximum value for increasing power (or frequency) of the "noise". This result shows that periodic signals applied extracellularly can improve the detection of subthreshold stochastic neural signals. The optimum frequency (110 Hz) is similar to that used in patients with Parkinson's suggesting that this phenomenon could play a role in the therapeutic effect of high frequency stimulation.

  12. [Cocaine-related gastric perforation].

    Science.gov (United States)

    Ring, A; Stein, E; Stern, J

    2010-06-01

    Since the 1980s the abuse of cocaine has been -associated with gastroduodenal perforations in the United States. Here, we report the case of a 28-year-old man who came to our hospital with severe abdominal pain after smoking cocaine. Physical examination revealed generalised abdominal guarding. His X-ray did not show any free intraperitoneal air. However, there was a slightly elevated white blood cell count. Upon laparoscopic exploration of the abdomen, the -patient was found to have a generalised peritonitis secondary to a perforation of the prepyloric anterior wall. The operative procedure consisted of ulcer excision and primary closure with a pyloroplasty as well as an extensive abdominal irrigation after laparotomy.

  13. Combining rhinoplasty with septal perforation repair.

    Science.gov (United States)

    Foda, Hossam M T; Magdy, Emad A

    2006-11-01

    A combined septal perforation repair and rhinoplasty was performed in 80 patients presenting with septal perforations (size 1 to 5 cm) and external nasal deformities. The external rhinoplasty approach was used for all cases and the perforation was repaired using bilateral intranasal mucosal advancement flaps with a connective tissue interposition graft in between. Complete closure of the perforation was achieved in 90% of perforations of size up to 3.5 cm and in only 70% of perforations that were larger than 3.5 cm. Cosmetically, 95% were very satisfied with their aesthetic result. The external rhinoplasty approach proved to be very helpful in the process of septal perforation repair especially in large and posteriorly located perforations and in cases where the caudal septal cartilage was previously resected. Our results show that septal perforation repair can be safely combined with rhinoplasty and that some of the routine rhinoplasty maneuvers, such as medial osteotomies and dorsal lowering, could even facilitate the process of septal perforation repair.

  14. CT in acute perforated sigmoid diverticulitis

    Energy Technology Data Exchange (ETDEWEB)

    Lohrmann, Christian [Division of Diagnostic Radiology, Department of Radiology, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany)]. E-mail: lohrmann@mrs1.ukl.uni-freiburg.de; Ghanem, Nadir [Division of Diagnostic Radiology, Department of Radiology, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Pache, Gregor [Division of Diagnostic Radiology, Department of Radiology, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Makowiec, Frank [Department of Surgery, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Kotter, Elmar [Division of Diagnostic Radiology, Department of Radiology, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Langer, Mathias [Division of Diagnostic Radiology, Department of Radiology, University Hospital of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany)

    2005-10-01

    Background: To assess the value of computed tomography (CT) in patients with acute perforated sigmoid diverticulitis in correlation with the Hinchey classification of perforated diverticular disease. Methods: Thirty patients with acute perforated sigmoid diverticulitis underwent computed tomography prior to surgery. Computed tomography scans were compared with the surgical and histopathological reports, utilizing the Hinchey classification. Results: In 28 of the 30 (93%) patients examined, the Hinchey stage was correctly determined by means of computed tomography. One patient with Hinchey stage IV was falsely classified as Hinchey stage III, and one patient with Hinchey stage III as Hinchey stage II. Computed tomography revealed 12 out of 14 (86%) patients with perforation sites and 3 out of 3 (100%) patients with contained perforation. In one of 17 (6%) patients with surgically or histopathologically proven perforation or contained perforation, a bowel wall discontinuity was revealed by computed tomography. In 6 of the 17 (35%) patients with surgical or histopathological perforation or contained perforation, extraluminal contrast material was detected by computed tomography. Conclusions: Computed tomography is a valuable imaging tool for determining the degree of acute perforated sigmoid diverticulitis, by means of which patients can be stratified according to the severity of the disease; furthermore, this tool is of assistance in surgical planning.

  15. Colonic perforation in Behcet's syndrome

    Institute of Scientific and Technical Information of China (English)

    Catherine M Dowling; Arnold DK Hill; Carmel Malone; John J Sheehan; Shona Tormey; Kieran Sheahan; Enda McDermott; Niall J O'Higgins

    2008-01-01

    A 17-year-old gentleman was admitted to our hospital for headache, the differential diagnosis of which included Behcet's syndrome (BS). He developed an acute abdomen and was found to have air under the diaphragm on erect chest X-ray. Subsequent laparotomy revealed multiple perforations throughout the colon. This report describes an unusual complication of Behcets syndrome occurring at the time of presentation and a review of the current literature of reported cases.

  16. Colonic perforation in Behcet's syndrome.

    Science.gov (United States)

    Dowling, Catherine-M; Hill, Arnold-Dk; Malone, Carmel; Sheehan, John-J; Tormey, Shona; Sheahan, Kieran; McDermott, Enda; O'Higgins, Niall-J

    2008-11-14

    A 17-year-old gentleman was admitted to our hospital for headache, the differential diagnosis of which included Behcet's syndrome (BS). He developed an acute abdomen and was found to have air under the diaphragm on erect chest X-ray. Subsequent laparotomy revealed multiple perforations throughout the colon. This report describes an unusual complication of Behcets syndrome occurring at the time of presentation and a review of the current literature of reported cases.

  17. Perforating Disseminated Necrobiosis Lipoidica Diabeticorum

    OpenAIRE

    Paula Lozanova; Lyubomir Dourmishev; Snejina Vassileva; Ljubka Miteva; Maria Balabanova

    2013-01-01

    Perforating necrobiosis lipoidica is a very rare clinical variant which consists of degeneration and transepidermal elimination of the collagen with few cases reported in the literature. In two-thirds of the patients it associates with diabetes, with no relation with the glucose control. We present a 42-year-old female patient with a 7-year history of diabetes on insulin therapy, referred to our clinic with a 3-year history of multiple asymptomatic firm plaques disseminated on the upper and l...

  18. Intraperitoneal explosion following gastric perforation.

    Science.gov (United States)

    Mansfield, Scott K; Borrowdale, Roderick

    2014-04-01

    The object of this study is to report a rare case of explosion during laparotomy where diathermy ignited intraperitoneal gas from a spontaneous stomach perforation. Fortunately, the patient survived but the surgeon experienced a finger burn. A literature review demonstrates other examples of intraoperative explosion where gastrointestinal gases were the fuel source. Lessons learned from these cases provide recommendations to prevent this potentially lethal event from occurring.

  19. Perforated duodenal ulcer: Emerging pattern

    Directory of Open Access Journals (Sweden)

    Murtaza Ali Asger Calcuttawala

    2014-01-01

    Full Text Available Background: A total of 27 patients of perforated duodenal ulcer admitted in our institution between December 2010 and November 2012 were treated and studied. Materials and Methods: All patients were diagnosed on the basis of clinical and radiological findings, exploratory laparotomy was performed and simple closure of perforation with placement of Graham′s omental patch was carried out. This was followed by triple regimen for Helicobacter pylori eradication. Results: All patients were male, maximum incidence (61.54% was noted in the age group of 21-30, ′O′ +ve blood group was most commonly observed in our patients. Eight patients had history suggestive of acute acid peptic disease. Mean time interval between the start of symptoms and surgery was 43 h. No morbidity except minimal pleural effusion was seen in one case. There was no mortality in our series. Conclusion: We conclude that although a number of definitive surgeries have been described for acid peptic disease, but the requirement of such procedures has come down due to increasing use of H. pylori eradication therapy and proton pump inhibitors. However, surgery for complications especially for duodenal ulcer perforation has not reduced concomitantly. Incidence is greater in young males.

  20. Freestyle Local Perforator Flaps for Facial Reconstruction

    Directory of Open Access Journals (Sweden)

    Jun Yong Lee

    2015-01-01

    Full Text Available For the successful reconstruction of facial defects, various perforator flaps have been used in single-stage surgery, where tissues are moved to adjacent defect sites. Our group successfully performed perforator flap surgery on 17 patients with small to moderate facial defects that affected the functional and aesthetic features of their faces. Of four complicated cases, three developed venous congestion, which resolved in the subacute postoperative period, and one patient with partial necrosis underwent minor revision. We reviewed the literature on freestyle perforator flaps for facial defect reconstruction and focused on English articles published in the last five years. With the advance of knowledge regarding the vascular anatomy of pedicled perforator flaps in the face, we found that some perforator flaps can improve functional and aesthetic reconstruction for the facial defects. We suggest that freestyle facial perforator flaps can serve as alternative, safe, and versatile treatment modalities for covering small to moderate facial defects.

  1. Freestyle Local Perforator Flaps for Facial Reconstruction.

    Science.gov (United States)

    Lee, Jun Yong; Kim, Ji Min; Kwon, Ho; Jung, Sung-No; Shim, Hyung Sup; Kim, Sang Wha

    2015-01-01

    For the successful reconstruction of facial defects, various perforator flaps have been used in single-stage surgery, where tissues are moved to adjacent defect sites. Our group successfully performed perforator flap surgery on 17 patients with small to moderate facial defects that affected the functional and aesthetic features of their faces. Of four complicated cases, three developed venous congestion, which resolved in the subacute postoperative period, and one patient with partial necrosis underwent minor revision. We reviewed the literature on freestyle perforator flaps for facial defect reconstruction and focused on English articles published in the last five years. With the advance of knowledge regarding the vascular anatomy of pedicled perforator flaps in the face, we found that some perforator flaps can improve functional and aesthetic reconstruction for the facial defects. We suggest that freestyle facial perforator flaps can serve as alternative, safe, and versatile treatment modalities for covering small to moderate facial defects.

  2. Dimensions of stabident intraosseous perforators and needles.

    Science.gov (United States)

    Ramlee, R A; Whitworth, J

    2001-09-01

    Problems can be encountered inserting intraosseous injection needles through perforation sites. This in vitro study examined the variability and size compatibility of Stabident intraosseous injection components. The diameters of 40 needles and perforators from a single Stabident kit were measured in triplicate with a toolmakers microscope. One-way ANOVA revealed that mean needle diameter (0.411 mm) was significantly narrower than mean perforator diameter (0.427 mm) (p < 0.001). A frequency distribution plot revealed that needle diameter followed a normal distribution, indicating tight quality control during manufacture. The diameter of perforators was haphazardly distributed, with a clustering of 15% at the lower limit of the size range. However on no occasion was the diameter of a perforator smaller than that of an injection needle. We conclude that components of the Stabident intraosseous anaesthetic system are size-compatible, but there is greater and more haphazard variability in the diameter of perforators than injection needles.

  3. Diagnosis of perforated gastric ulcers by ultrasound.

    Science.gov (United States)

    Wallstabe, L; Veitt, R; Körner, T

    2002-10-01

    Patients with a perforation of the gastrointestinal tract need fast confirmation of diagnosis and early treatment to improve outcome. Plain abdominal x-ray does not always prove the perforation particularly at early stage. We report about a 62 year-old woman complaining of consistent abdominal pain with sudden onset. Ultrasound was taken as first diagnostic measure, revealing a perforation. The leakage was located in the stomach. Radiography confirmed the pneumoperitoneum without indicating the perforated location. During operation the perforated gastric ulcer was found and sutured. This case report points out the reliability of ultrasound in diagnosing a pneumoperitoneum. Additionally it provides a summary of ultrasound signs seen in perforated gastric and duodenal ulcers and a review of literature.

  4. Stercoral colonic diverticulum perforation with jejunal diverticulitis mimicking upper gastrointestinal perforation

    Institute of Scientific and Technical Information of China (English)

    BI Jing-tao; GUO Yan-tong; ZHAO Jing-ming; ZHANG Zhong-tao

    2012-01-01

    Stercoral perforation of the colon is an unusual pathological condition with fewer than 150 cases reported in the literature to date.We present a case of stercoral colonic perforation mimicking upper gastrointestinal perforation,which was diagnosed by computed tomography preoperatively.However,at laparotomy,stercoral colonic diverticulum perforation with jejunal diverticulitis became the most appropriate diagnosis.Colonic perforation is a severe complication in surgery.It is a rather uncommon event usually caused by malignancy,diverticular disease,trauma or ulcerative colitis.Stercoral perforation of the colon was reported by Berry1 in 1894.Fewer than 150 cases have been reported in the literature to date.2,3 We present a rare case of stercoral diverticulum colonic perforation with jejunal diverticulitis mimicking upper gastrointestinal (GI) perforation,which was correctly diagnosed at laparotomy.

  5. A CALCULUS CHOLECYSTITIS PERFORATING AT THE NECK

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    Jayashri

    2014-08-01

    Full Text Available Gallbladder perforation is a rare complication of cholecystitis and cholelithiasis. The high morbidity and mortality rates associated with this condition are due to delays in diagnosis and treatment since signs and symptoms of perforation do not differ significantly from those of uncomplicated cholecystitis. We report a case of 17 year old boy who presented with perforation at the neck of gall bladder with extrusion of a stone. It was associated with bile infected with S. typhi.

  6. Spontaneous ileal perforation complicating low anorectal malformation

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    TiJesuni Olatunji

    2015-01-01

    Full Text Available Anorectal malformation is a common anomaly in neonates. Although colorectal perforations have been reported as a complication, ileal perforation is rarely encountered. This is a report of a 2-day-old boy presenting with a low anorectal malformation, complicated with ileal perforation, necessitating laparotomy and ileal repair. Anoplasty was done for the low anomaly. Early presentation and prompt treatment of anorectal malformations is important to prevent such potential life threatening complication.

  7. Management of biliary perforation in children

    Directory of Open Access Journals (Sweden)

    Mirza Bilal

    2010-01-01

    Full Text Available Background: To study the aetiology, management and outcome of biliary perforations in paediatric age group. Patients and Methods: In a retrospective study, the records of patients presented with biliary peritonitis due to biliary perforations, managed from March 2006 to July 2009, are reviewed. Results: Eight male patients with biliary peritonitis due to biliary perforation were managed. These patients were divided in two groups, A and B. Group A, (n = 3 patients, had common bile duct (CBD perforation, and Group B (n=5 patients had gallbladder perforation. The presenting features were abdominal pain, fever, abdominal distension, vomiting, constipation, jaundice and signs of peritonism. The management of CBD perforations in Group A was by draining the site of perforation and biliary diversion (tube cholecystostomy. In Group B, the gallbladder perforations were managed by tube cholecystostomy in four patients and cholecystectomy in one patient, however, one patient had to be re-explored and cholecystectomy performed due to complete necrosis of gall bladder. There was no mortality in our series. All patients were asymptomatic on regular follow-up. Conclusion: Early optimal management of biliary perforations remarkably improved the very high mortality and morbidity that characterised this condition in the past.

  8. Input-to-output transformation in a model of the rat hippocampal CA1 network

    OpenAIRE

    Olypher, Andrey V; Lytton, William W; Prinz, Astrid A.

    2012-01-01

    Here we use computational modeling to gain new insights into the transformation of inputs in hippocampal field CA1. We considered input-output transformation in CA1 principal cells of the rat hippocampus, with activity synchronized by population gamma oscillations. Prior experiments have shown that such synchronization is especially strong for cells within one millimeter of each other. We therefore simulated a one-millimeter patch of CA1 with 23,500 principal cells. We used morphologically an...

  9. Altered network timing in the CA3-CA1 circuit of hippocampal slices from aged mice.

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    Daniel J Kanak

    Full Text Available Network patterns are believed to provide unique temporal contexts for coordinating neuronal activity within and across different regions of the brain. Some of the characteristics of network patterns modeled in vitro are altered in the CA3 or CA1 subregions of hippocampal slices from aged mice. CA3-CA1 network interactions have not been examined previously. We used slices from aged and adult mice to model spontaneous sharp wave ripples and carbachol-induced gamma oscillations, and compared measures of CA3-CA1 network timing between age groups. Coherent sharp wave ripples and gamma oscillations were evident in the CA3-CA1 circuit in both age groups, but the relative timing of activity in CA1 stratum pyramidale was delayed in the aged. In another sample of aged slices, evoked Schaffer collateral responses were attenuated in CA3 (antidromic spike amplitude and CA1 (orthodromic field EPSP slope. However, the amplitude and timing of spontaneous sharp waves recorded in CA1 stratum radiatum were similar to adults. In both age groups unit activity recorded juxtacellularly from unidentified neurons in CA1 stratum pyramidale and stratum oriens was temporally modulated by CA3 ripples. However, aged neurons exhibited reduced spike probability during the early cycles of the CA3 ripple oscillation. These findings suggest that aging disrupts the coordination of patterned activity in the CA3-CA1 circuit.

  10. Iatrogenic esophageal perforation in a newborn

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Mi; Yeon, Kyung Mo; Park, Won Soon; Choi, Jung Hwan [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    1990-07-15

    Esophagus and pharyngeal structures of newborn are very week and so vulnerable. When a parallel longitudinal tubular structure around (especially behind) the esophagus is seen, traumatic esophageal perforation must be differentiated. We report a case of esophageal perforation in a premature twin baby by nasogastric tube insertion.

  11. [Methods for sealing of corneal perforations].

    Science.gov (United States)

    Samoilă, O; Totu, Lăcrămioara; Călugăru, M

    2012-01-01

    A variety of corneal pathology can lead to corneal ulcers and perforations. A deep corneal ulcer may need surgical treatment to allow good volume restoration and reepithelisation. Corneal perforation must be sealed and when the perforation is large, the task of repairing the defect can be underwhelming. The elegant solution is the corneal transplant, but this is not always readily available, especially in undeveloped countries. We present here two cases with different solutions to seal the perforated cornea: the first one has a large peripheral defect and it is successfully sealed with scleral patch and the second one is central with small perforation and is successfully sealed with multilayered amniotic membrane. Both cases are followed for over 12 months and demonstrate good corneal restoration (both on clinical examination and corneal topography). Sclera and amniotic membrane can be used to seal corneal defects when corneal transplant is not readily available.

  12. Intestinal perforation secondary to metastasic lung carcinoma

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    M. C. Álvarez Sánchez

    2014-11-01

    Full Text Available Secondary symptomatic gastrointestinal metastases from lung primary tumor are rare. They can cause a variety of clinical conditions such as perforation, obstruction and bleeding. Intestinal perforations of intestinal metastases have a very poor prognosis. We present a case of a patient with metastatic lung cancer who presents with intestinal perforation and pneumoperitoneum. A 67 year old male, immunosuppressed and smoker is diagnosed with acute abdomen secondary to perforation of a tumor of the terminal ileum, as well as three other similar injuries. Resection and anastomosis. The patient died two months after surgery. The final pathological diagnosis supports epidermoidide poorly differentiated lung carcinoma. It was concluded that given an intestinal perforation in a patient diagnosed with lung carcinoma, it shouldn´t be excluded the metastases origen . Surgery is a purely palliative procedure.

  13. [Gastric perforation associated with Candida infection].

    Science.gov (United States)

    Bollo, Jesús; Carrilo, Elena; Lupu, Ion; Caballero, Ferran; Trias, Manel

    2009-01-01

    Notable causes of gastroduodenal ulcer are Helicobacter pylori infection, intake of non-steroidal anti-inflammatory agents, neoplastic disease, acid hypersecretory states and secondary peptic ulcer disease. There are case reports of healthy patients or those with risk factors for fungal infection who develop gastroduodenal ulcer perforation associated with the presence of fungi in ascitic fluid or gastroduodenal ulcer tissue but without the above-mentioned etiological factors. Thus, other factors and pathogens may be involved in the pathogenesis of perforation. The use of antifungal agents in patients following surgery for a perforated gastroduodenal ulcer is controversial. We report two cases of healthy patients who underwent surgery for perforated gastroduodenal ulcer, in whom the most frequent causes of perforation were excluded. Only the presence of Candida in the ulcer was found.

  14. Imidacloprid toxicity impairs spatial memory of echolocation bats through neural apoptosis in hippocampal CA1 and medial entorhinal cortex areas.

    Science.gov (United States)

    Hsiao, Chun-Jen; Lin, Ching-Lung; Lin, Tian-Yu; Wang, Sheue-Er; Wu, Chung-Hsin

    2016-04-13

    It has been reported that the decimation of honey bees was because of pesticides of imidacloprid. The imidacloprid is a wildly used neonicotinoid insecticide. However, whether imidacloprid toxicity interferes with the spatial memory of echolocation bats is still unclear. Thus, we compared the spatial memory of Formosan leaf-nosed bats, Hipposideros terasensis, before and after chronic treatment with a low dose of imidacloprid. We observed that stereotyped flight patterns of echolocation bats that received chronic imidacloprid treatment were quite different from their originally learned paths. We further found that neural apoptosis in hippocampal CA1 and medial entorhinal cortex areas of echolocation bats that received imidacloprid treatment was significantly enhanced in comparison with echolocation bats that received sham treatment. Thus, we suggest that imidacloprid toxicity may interfere with the spatial memory of echolocation bats through neural apoptosis in hippocampal CA1 and medial entorhinal cortex areas. The results provide direct evidence that pesticide toxicity causes a spatial memory disorder in echolocation bats. This implies that agricultural pesticides may pose severe threats to the survival of echolocation bats.

  15. CHEMICAL CAUTERISATION OF TYMPANIC MEMBRANE PERFORATIONS

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    Vikramjit Singh

    2015-04-01

    Full Text Available Cauterisation of 144 ear perforations ( R ight and L eft with 20 percent TCA ( T richloracetic acid was tried in patients having 2 to 6mm perforations . Per forations were dry for 3 weeks - 3 months or more. 30 patients were having traumatic perforations such as slap on face, blast injuries or associated with head injuries. Most of the patients were having perforations due to inflammation. Few of them had recent attack of otitis media which were effectively treated by suitable antibiotics, anti - histamines and subs equently taken for cauterization of perforation. Site of perforation was mostly on the anteroinferior quadrant, next the inferior quadrants. Still less number in the entire four quadrant, least no. in P. S. quadrant. Traumatic perforations were irr egular i n shape varying from 2 - 6 mm in size and were elliptical in shape. Hearing loss ranged from 15dB - 45dB ( D epending upon size and site of perforation. Main presenting symptoms in inflammation cases were intermittent discharge as well as deafness. In traumatic case history of pain and deafness was the main symptom. We did wait for 1 month in traumatic cases to achieve spontaneous closure. In inflammatory cases cautery was considered first line of treatment. It has to be done several times at 10 days interval. Mo st of the times closure of perforation was achieved with 3 attempts, inflammatory cases 5 th or 6 th attempt. In one case as many as 23 attempts. In 6 cases of perforation after partial take of graft in myringoplasty occurred after 3 months cauterization was attempted and we got closure in 5 of them. In one case re myringoplasty had to be done.

  16. Environmental novelty elicits a later theta phase of firing in CA1 but not subiculum.

    Science.gov (United States)

    Lever, Colin; Burton, Stephen; Jeewajee, Ali; Wills, Thomas J; Cacucci, Francesca; Burgess, Neil; O'Keefe, John

    2010-02-01

    The mechanism supporting the role of the hippocampal formation in novelty detection remains controversial. A comparator function has been variously ascribed to CA1 or subiculum, whereas the theta rhythm has been suggested to separate neural firing into encoding and retrieval phases. We investigated theta phase of firing in principal cells in subiculum and CA1 as rats foraged in familiar and novel environments. We found that the preferred theta phase of firing in CA1, but not subiculum, was shifted to a later phase of the theta cycle during environmental novelty. Furthermore, the amount of phase shift elicited by environmental change correlated with the extent of place cell remapping in CA1. Our results support a relationship between theta phase and novelty-induced plasticity in CA1.

  17. Numerical Simulation on New Perforator

    Institute of Scientific and Technical Information of China (English)

    姚志华; 王志军; 李德战; 付盟

    2011-01-01

    To study a new shaped charge of perforator, the jet formation and penetration processes in concrete targets are simulated numerically by using LS-DYNA finite element analysis software. The results show that the cylindrical liner can form jet and most materials on top of liner form the tip of jet, while the others form the tail of jet. The jet has a better continuity, and the ratio of cumulative jet length to the liner diameter can reach to 7.56. Furthermore, the ratio of bore diameter to the liner diameter is from 0. 36 and 1, and the ratio of penetration depth to the liner diameter can be up to 5.5.

  18. Diagnosis and treatment of gallbladder perforation

    Institute of Scientific and Technical Information of China (English)

    Hayrullah Derici; Cemal Kara; Ali Dogan Bozdag; Okay Nazli; Tugrul Tansug; Esra Akca

    2006-01-01

    AIM: To present our clinical experience with gallbladder perforation cases.METHODS: Records of 332 patients who received medical and/or surgical treatment with the diagnosis of acute cholecystitis in our clinic between 1997 and 2006 were reviewed retrospectively. Sixteen (4.8%) of those patients had gallbladder perforation. The parameters including age, gender, time from the onset of symptoms to the time of surgery, diagnostic procedures, surgical treatment, morbidity, and mortality were evaluated.RESULTS: Seven patients had type Ⅰ gallbladder perforation, 7 type Ⅱ gallbladder perforation, and 2 type Ⅲ gallbladder perforation according to Niemeier's classification. The patients underwent surgery after administration of intravenous electrolyte solutions, and were treated with analgesics and antibiotics within the first 36 h (mean 9 h) after admission. Two patients died of sepsis and multiple organ failure in the early postoperative period. Subhepatic abscess, pelvic abscess,pneumonia, pancreatitis, and acute renal failure were found in 6 patients.CONCLUSION: Early diagnosis and emergency surgical treatment of gallbladder perforation are of crucial importance. Upper abdominal computerized tomography for acute cholecystitis patients may contribute to the preoperative diagnosis of gallbladder perforation.

  19. Intestinal perforation by an ingested foreign body*

    Science.gov (United States)

    Nicolodi, Gabriel Cleve; Trippia, Cesar Rodrigo; Caboclo, Maria Fernanda F. S.; de Castro, Francisco Gomes; Miller, Wagner Peitl; de Lima, Raphael Rodrigues; Tazima, Leandro; Geraldo, Jamylle

    2016-01-01

    Objective To identify the computed tomography findings suggestive of intestinal perforation by an ingested foreign body. Materials and Methods This was a retrospective study of four cases of surgically proven intestinal perforation by a foreign body, comparing the computed tomography findings with those described in the literature. Results None of the patients reported having ingested a foreign body, all were over 60 years of age, three of the four patients used a dental prosthesis, and all of the foreign bodies were elongated and sharp. In all four patients, there were findings indicative of acute abdomen. None of the foreign bodies were identified on conventional X-rays. The computed tomography findings suggestive of perforation were thickening of the intestinal walls (in all four cases), increased density of mesenteric fat (in all four cases), identification of the foreign body passing through the intestinal wall (in three cases), and gas in the peritoneal cavity (in one case). Conclusion In cases of foreign body ingestion, intestinal perforation is more common when the foreign body is elongated and sharp. Although patients typically do not report having ingested such foreign bodies, the scenario should be suspected in elderly individuals who use dental prostheses. A computed tomography scan can detect foreign bodies, locate perforations, and guide treatment. The findings that suggest perforation are thickening of the intestinal walls, increased mesenteric fat density, and, less frequently, gas in the peritoneal cavity, often restricted to the point of perforation. PMID:27818542

  20. Intestinal perforation by an ingested foreign body

    Directory of Open Access Journals (Sweden)

    Gabriel Cleve Nicolodi

    Full Text Available Abstract Objective: To identify the computed tomography findings suggestive of intestinal perforation by an ingested foreign body. Materials and Methods: This was a retrospective study of four cases of surgically proven intestinal perforation by a foreign body, comparing the computed tomography findings with those described in the literature. Results: None of the patients reported having ingested a foreign body, all were over 60 years of age, three of the four patients used a dental prosthesis, and all of the foreign bodies were elongated and sharp. In all four patients, there were findings indicative of acute abdomen. None of the foreign bodies were identified on conventional X-rays. The computed tomography findings suggestive of perforation were thickening of the intestinal walls (in all four cases, increased density of mesenteric fat (in all four cases, identification of the foreign body passing through the intestinal wall (in three cases, and gas in the peritoneal cavity (in one case. Conclusion: In cases of foreign body ingestion, intestinal perforation is more common when the foreign body is elongated and sharp. Although patients typically do not report having ingested such foreign bodies, the scenario should be suspected in elderly individuals who use dental prostheses. A computed tomography scan can detect foreign bodies, locate perforations, and guide treatment. The findings that suggest perforation are thickening of the intestinal walls, increased mesenteric fat density, and, less frequently, gas in the peritoneal cavity, often restricted to the point of perforation.

  1. Path Sensitization

    Institute of Scientific and Technical Information of China (English)

    赵著行; 闵应骅; 等

    1997-01-01

    For different delay models,the concept of sensitization can be very different.Traditonal concepts of sensitization cannot precisely describe circuit behavior when the input vectors change very fast.Using Boolean process aporoach,this paper presents a new definition of sensitization for arbitrary input waveforms.By this new concept it is found that if the inputs of a combinational circuit can change at any time,and each gate's delay varies within an interval (bounded gate delay model),then every path,which is not necessarily a single topological path,is sensitizable.From the experimental results it can be seen that,all nonsensitizable paths for traditional concepts actually can propagate transitions along them for some input waveforms.However,specified time between input transitions(STBIT) and minimum permissible pulse width(ε)are two major factors to make some paths non-sensitizable.

  2. Nasal Septum Perforation due to Methamphetamine abuse

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    Mehdi Bakhshaee

    2012-07-01

    Full Text Available Introduction: Spontaneous Perforation of the nasal septum is an uncommon condition. Nasal inhalation of substances such as cocaine has long been linked to this Perforation. Case Report: This report describes the case of a 46-year-old woman who was addicted to methamphetamine and who presented with perforation of the nasal septum.This is the first reported case of nasal septal necrosis linked to nasal inhalation of methamphetamine. Conclusions: Patient history and assurance regardingillegal drug consumption and abuse is a key point for fast and accurate diagnosis. The pathophysiology of drug-induced sinunasal disease and a review of the literature are also presented.

  3. Septum nasal perforation: treatments and literature' review

    Directory of Open Access Journals (Sweden)

    Martinez Neto, Eulógio Emílio

    2010-03-01

    Full Text Available Introduction: The present study consists in a bibliographical' review concerning the articles related to the different manifestations and forms of the septum nasal perforation, with a main emphasis in the description of its techniques of surgical correction. As the etiology, that is fundamentally iatrogenic, accordingly surgical trauma. Other causes include exhibition to chemical industrial reagents, cocaine use, intranasal steroidal therapeutic, neoplasia and, infectious conditions. There is a few data concerning the prevalence of septum perforation in the general population. The decision making about surgical correction or medical treatment depend on the anatomic characteristics and of the pathogenesis of the septal perforation.

  4. Modelling of acoustic transmission through perforated layer

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    Lukeš V.

    2007-10-01

    Full Text Available The paper deals with modeling the acoustic transmission through a perforated interface plane separating two halfspaces occupied by the acoustic medium. We considered the two-scale homogenization limit of the standard acoustic problem imposed in the layer with the perforated periodic structure embedded inside. The homogenized transmission conditions govern the interface discontinuity of the acoustic pressure associated with the two halfspaces and the magnitude of the fictitious transversal acoustic velocity. By numerical examples we illustrate this novel approach of modeling the acoustic impedance of perforated interfaces.

  5. Traumatic prenatal sigmoid perforation due to amniocentesis

    Energy Technology Data Exchange (ETDEWEB)

    Fines, B.; Ben-Ami, T.E.; Yousefzadeh, D.K. [Dept. of Radiology, Univ. of Chicago, IL (United States)

    2001-06-01

    A variety of fetal injuries, including those inflicted to the gastrointestinal tract by amniocentesis, have been reported before. This brief report describes the first documented case of sigmoid perforation owing to the common procedure of amniocentesis that manifested as abdominal distention at birth. A potential link between this complication and a recent increased incidence of ''intrauterine spontaneous perforation'' of the gastrointestinal tract has been mentioned. Practicing radiologists are encouraged to inquire directly about the history of amniocentesis in unexplained cases of intrauterine intestinal perforation. (orig.)

  6. Effect of Perforation Area and Arrangement Pattern on Structural Behaviour of Nature Inspired Perforated Hollow Structure

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    Woo Yian Peen

    2013-01-01

    Full Text Available The Cholla cactus skeleton has been the inspiration source for this study, in our effort to search forlight and more structural effective structures. This woody skeleton of Cholla with oval shaped perforationsarranged in spiral pattern is found strong enough to support the cactus self weight. This research has beencarried out to investigate the effects of percentage of perforations and perforations arrangements on structuralbehaviour of cylindrical hollow section. A total of eleven models consisting of one cylindrical hollow sectionwithout perforation as the control model and ten simplified perforated cylindrical hollow sections have beenconstructed using a finite element method software. The perforated models have been assigned with 10 to 50percent of perforations area by fixing the number of perforations to twenty and altering the perforation size toachieve the percentage variable. Computational analyses have been carried out for three loading conditions:compressive, flexural and torsional. Findings have shown that the increment in percentage of perforationsproduces higher stresses to the cylindrical hollow section. This has effects on the structural capacity of thecylindrical hollow section. Array arrangement of the perforations shows better structural performance incompression and flexural loading conditions while spiral arrangement exhibits better structural performanceunder torsional loading condition.

  7. Stercoral perforation in a 17-year old.

    LENUS (Irish Health Repository)

    McHugh, S

    2009-04-02

    INTRODUCTION: Stercoral perforation is a rare cause of perforation. This is the first reported case where a partial eating disorder (ED) is the primary causative differential. CASE PRESENTATION: We present the case of a 17-year-old girl who presented to her local Emergency Department with a 24-h history of left-sided abdominal pain. She subsequently deteriorated and a computed tomography scan of her abdomen showed gross distension of the large bowel with a sigmoid perforation. She underwent total colectomy with end ileostomy. Histology reported stercoral perforation but normal bowel ganglia. While an inpatient she was reviewed by the Psychiatric team who were concerned she was suffering from a partial ED. CONCLUSION: This case highlights the importance of a multidisciplinary approach in optimally treating patients such as these. Aggressive medical management with involvement of a psychiatric team and dietetics addresses any underlying causative psychiatric issues and helps prevent recurrence.

  8. Diagnosis and management of iatrogenic endoscopic perforations

    DEFF Research Database (Denmark)

    Paspatis, Gregorios A; Dumonceau, Jean-Marc; Barthet, Marc

    2014-01-01

    This Position Paper is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the diagnosis and management of iatrogenic perforation occurring during diagnostic or therapeutic digestive endoscopic procedures. Main recommendations 1 ESGE recommends that ea...

  9. Laparoscopic Repair for Perforated Duodenal Ulcer

    Directory of Open Access Journals (Sweden)

    A. Cotirleţ

    2015-01-01

    Full Text Available Perforated peptic ulcer (PPU, despite antiulcer medication and Helicobacter eradication, is still the most common indication for emergency gastric surgery associated with high morbidity and mortality. Perforated peptic ulcer is a common abdominal disease that is treated by surgery. The development of laparoscopic surgery has changed the way to treat such abdominal surgical emergencies but there is no consensus on whether the benefits of laparoscopic closure of perforated peptic ulcer outweigh the disadvantages such as prolonged surgery time and greater expense. However we can say that laparoscopic repair is a viable and safe surgical option for patients with perforated peptic ulcer disease and should be considered with the necessary expertise available.

  10. Stercoral perforation in a 17-year old.

    LENUS (Irish Health Repository)

    McHugh, S

    2012-02-01

    INTRODUCTION: Stercoral perforation is a rare cause of perforation. This is the first reported case where a partial eating disorder (ED) is the primary causative differential. CASE PRESENTATION: We present the case of a 17-year-old girl who presented to her local Emergency Department with a 24-h history of left-sided abdominal pain. She subsequently deteriorated and a computed tomography scan of her abdomen showed gross distension of the large bowel with a sigmoid perforation. She underwent total colectomy with end ileostomy. Histology reported stercoral perforation but normal bowel ganglia. While an inpatient she was reviewed by the Psychiatric team who were concerned she was suffering from a partial ED. CONCLUSION: This case highlights the importance of a multidisciplinary approach in optimally treating patients such as these. Aggressive medical management with involvement of a psychiatric team and dietetics addresses any underlying causative psychiatric issues and helps prevent recurrence.

  11. Perforated peptic ulcer: How to improve outcome?

    DEFF Research Database (Denmark)

    Møller, Morten Hylander; Adamsen, Sven; Wøjdemann, Morten;

    2008-01-01

    Despite the introduction of histamine H(2)-receptor antagonists, proton-pump inhibitors and the discovery of Helicobacter pylori, both the incidence of emergency surgery for perforated peptic ulcer and the mortality rate for patients undergoing surgery for peptic ulcer perforation have increased...... with an emphasis on risks that are preventable. A systematic review including randomized studies was carried out. There are a limited number of studies of patients with peptic ulcer perforation. Most of these studies are of low evidential status. Only a few randomized, controlled trials have been published...... to improve the outcome of patients with peptic ulcer perforation, sepsis needs to be factored into the existing knowledge and treatment Udgivelsesdato: 2008/8/27...

  12. Place cells are more strongly tied to landmarks in deep than in superficial CA1

    Science.gov (United States)

    Geiller, Tristan; Fattahi, Mohammad; Choi, June-Seek; Royer, Sébastien

    2017-01-01

    Environmental cues affect place cells responses, but whether this information is integrated versus segregated in distinct hippocampal cell populations is unclear. Here, we show that, in mice running on a treadmill enriched with visual-tactile landmarks, place cells are more strongly controlled by landmark-associated sensory inputs in deeper regions of CA1 pyramidal layer (CA1d). Many cells in CA1d display several firing fields correlated with landmarks, mapping positions slightly before or within the landmarks. Supporting direct involvement of sensory inputs, their firing fields show instantaneous responses to landmark manipulations, persist through change of context, and encode landmark identity and saliency. In contrast, cells located superficially in the pyramidal layer have single firing fields, are context specific and respond with slow dynamics to landmark manipulations. These findings suggest parallel and anatomically segregated circuits within CA1 pyramidal layer, with variable ties to landmarks, allowing flexible representation of spatial and non-spatial information. PMID:28218283

  13. Freestyle Local Perforator Flaps for Facial Reconstruction

    OpenAIRE

    Jun Yong Lee; Ji Min Kim; Ho Kwon; Sung-No Jung; Hyung Sup Shim; Sang Wha Kim

    2015-01-01

    For the successful reconstruction of facial defects, various perforator flaps have been used in single-stage surgery, where tissues are moved to adjacent defect sites. Our group successfully performed perforator flap surgery on 17 patients with small to moderate facial defects that affected the functional and aesthetic features of their faces. Of four complicated cases, three developed venous congestion, which resolved in the subacute postoperative period, and one patient with partial necrosi...

  14. Gall bladder perforation in acalculous cholecystitis

    OpenAIRE

    Dayananda Srinivasan; Sujith Sherigar; Durganna Thimmappa

    2014-01-01

    Acute acalculous cholecystitis is relatively rare as compared to the calculous cholecystitis. But complications like gangrenous changes and Gall bladder (GB) perforation is more common with acalculous variety than calculous cholecystitis.GB perforation following acalculous cholecystitis has a mortality of 10-50 % as compared to that of 1% following calculous cholecystitis. The literarature pertaining to this is very few and does not conclude a standard mangement in such cases. ...

  15. Ventriculoperitoneal shunt perforations of the gastrointestinal tract.

    Science.gov (United States)

    Thiong'o, Grace Muthoni; Luzzio, Christopher; Albright, A Leland

    2015-07-01

    OBJECT The purposes of this study were to evaluate the frequency with which children presented with ventriculoperitoneal (VP) shunt perforations of the gastrointestinal (GI) tract, to determine the type of shunts that caused the perforations, and to compare the stiffness of perforating catheters with the stiffness of catheters from other manufacturers. METHODS Medical records were reviewed of 197 children who were admitted with VP shunt malfunction. Catheter stiffness was evaluated by measuring relative resistance to cross-sectional compression, resistance to column buckling, and elasticity in longitudinal bending. Catheter frictional force was measured per unit length. RESULTS Six children were identified whose VP shunts had perforated the GI tract; 2 shunts subsequently protruded through the anal orifice, 1 protruded through the oral cavity, and 3 presented with subcutaneous abscesses that tracked upward from the intestine to the chest. All perforating shunts were Chhabra shunts. Catheter stiffness and resistance to bending were greatest with a Medtronic shunt catheter, intermediate with a Codman catheter, and least with a Chhabra catheter. Frictional force was greatest with a Chhabra catheter and least with a Medtronic catheter. CONCLUSIONS The frequency of perforations by Chhabra shunts appears to be higher than the frequency associated with other shunts. The increased frequency does not correlate with their stiffness but may reflect their greater frictional forces.

  16. Perforated duodenal ulcer in Asir central hospital

    Directory of Open Access Journals (Sweden)

    Jastaniah Suleiman

    1997-01-01

    Full Text Available In a study of 27 cases of perforated duodenal ulcer seen at Asir Central Hospital over a period of seven years, two patients were females and 25 males. The highest incidence was in the fourth decade and the average age was 36.3 years. The Saudi-foreigner ratio was 1:2.9 in an area where the Saudi-foreigner population ratio was 1:3. Nine patients (33.3% were previously diagnosed as having peptic ulcer and had received treatment at one time or the other before perforation. Eighteen patients (66.7% were first diagnosed to peptic ulcer after the perforation. All the identified perforations were located anteriorly and anterosuperiorly. Only one case occurred in the second part of duodenum. The rest occurred in the first part. Two patients were treated successfully conservatively. The month perforations occurred most was the month of Shaaban. The fasting period during the month of Ramadhan did not show any increase in the prevalence of perforation in this hospital.

  17. Surgical treatment of perforated gastric ulcer

    Directory of Open Access Journals (Sweden)

    Korica Milan

    2002-01-01

    Full Text Available Introduction Peptic ulcer perforation is a complication of ulcer disease which requires urgent surgical treatment. The aim of this paper was to point out our experience in surgical treatment of perforated peptic ulcer. Material and methods This retrospective study analyzes results of surgical treatment in 365 patients with perforated peptic ulcer during the period January 1996 to December 2000. Results During the last 5-year period 365 patients were treated following peptic ulcer perforation. The average age was 43.53±8.26, with the span from 18 to 86. The most frequent surgical procedures in treatment of peptic ulcer perforation were: simple closure with biopsy (55.88%, excision of the ulcer with a pyloroplasty and vagotomy (35.29% as nonresection surgical procedures and stomach resection after Billroth II (8.83%. The postoperative mortality was 4.41%. Conclusions The methods of choice in surgical treatment of gastric ulcer perforation are nonresection surgical procedures with drug therapy and eradication of Helicobacter pylori, if present.

  18. Fat graft myringoplasty in small central perforations

    Directory of Open Access Journals (Sweden)

    Chandni Sharma

    2014-01-01

    Full Text Available Background: Perforations of the tympanic membrane (TM are treated with various surgical techniques and materials. Although autologous temporalis fascia is the most common material used for the closure of TM perforations, however for a dry, small central perforation the fat graft myringoplasty (FM is a good alternative as it is a simple and cost-effective technique. Objectives: The aim of this study was to determine the efficacy of FM for repair of small central perforations. Suggestions for optimizing the outcome of FM are presented. Material and Methods: Twenty patients (10 males and 10 females who had uncomplicated dry small central perforation, which was confined to one quadrant of the pars tensa underwent FM. The outcome was evaluated after 1-week, 1-month, and 3 months. Results: After 3 months of follow-up, a closure rate of 80% was achieved. Mean preoperative air-bone (AB gap was 22.90 ± 6.54 dB and mean postoperative AB gap was 21.80 ± 6.28 dB. Mean improvement in AB gap postoperatively was 1.1 ± 2.63 dB. Conclusion: Fat graft myringoplasty, with its ease of technique and good graft uptake rate justifies its use in the closure of small dry central TM perforations.

  19. Input-to-output transformation in a model of the rat hippocampal CA1 network.

    Science.gov (United States)

    Olypher, Andrey V; Lytton, William W; Prinz, Astrid A

    2012-01-01

    Here we use computational modeling to gain new insights into the transformation of inputs in hippocampal field CA1. We considered input-output transformation in CA1 principal cells of the rat hippocampus, with activity synchronized by population gamma oscillations. Prior experiments have shown that such synchronization is especially strong for cells within one millimeter of each other. We therefore simulated a one-millimeter ıt patch of CA1 with 23,500 principal cells. We used morphologically and biophysically detailed neuronal models, each with more than 1000 compartments and thousands of synaptic inputs. Inputs came from binary patterns of spiking neurons from field CA3 and entorhinal cortex (EC). On average, each presynaptic pattern initiated action potentials in the same number of CA1 principal cells in the patch. We considered pairs of similar and pairs of distinct patterns. In all the cases CA1 strongly separated input patterns. However, CA1 cells were considerably more sensitive to small alterations in EC patterns compared to CA3 patterns. Our results can be used for comparison of input-to-output transformations in normal and pathological hippocampal networks.

  20. UCP3 Regulates Single-Channel Activity of the Cardiac mCa1.

    Science.gov (United States)

    Motloch, Lukas J; Gebing, Tina; Reda, Sara; Schwaiger, Astrid; Wolny, Martin; Hoppe, Uta C

    2016-08-01

    Mitochondrial Ca(2+) uptake (mCa(2+) uptake) is thought to be mediated by the mitochondrial Ca(2+) uniporter (MCU). UCP2 and UCP3 belong to a superfamily of mitochondrial ion transporters. Both proteins are expressed in the inner mitochondrial membrane of the heart. Recently, UCP2 was reported to modulate the function of the cardiac MCU related channel mCa1. However, the possible role of UCP3 in modulating cardiac mCa(2+) uptake via the MCU remains inconclusive. To understand the role of UCP3, we analyzed cardiac mCa1 single-channel activity in mitoplast-attached single-channel recordings from isolated murine cardiac mitoplasts, from adult wild-type controls (WT), and from UCP3 knockout mice (UCP3(-/-)). Single-channel registrations in UCP3(-/-) confirmed a murine voltage-gated Ca(2+) channel, i.e., mCa1, which was inhibited by Ru360. Compared to WT, mCa1 in UCP3(-/-) revealed similar single-channel characteristics. However, in UCP3(-/-) the channel exhibited decreased single-channel activity, which was insensitive to adenosine triphosphate (ATP) inhibition. Our results suggest that beyond UCP2, UCP3 also exhibits regulatory effects on cardiac mCa1/MCU function. Furthermore, we speculate that UCP3 might modulate previously described inhibitory effects of ATP on mCa1/MCU activity as well.

  1. Path Dependence

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    Begrebet Path Dependence blev oprindelig udviklet inden for New Institutionel Economics af bl.a. David, Arthur og North. Begrebet har spredt sig vidt i samfundsvidenskaberne og undergået en udvikling. Dette paper propagerer for at der er sket så en så omfattende udvikling af begrebet, at man nu kan...... tale om 1. og 2. generation af Path Dependence begrebet. Den nyeste udvikling af begrebet har relevans for metodologi-diskusionerne i relation til Keynes...

  2. Spectrum of perforation peritonitis in Pakistan: 300 cases Eastern experience

    Directory of Open Access Journals (Sweden)

    Ur-Rahman Shafiq

    2008-11-01

    Full Text Available Abstract Background Perforation peritonitis is the most common surgical emergency encountered by the surgeons all over the world as well in Pakistan. The spectrum of etiology of perforation peritonitis in tropical countries continues to differ from its western counter part. This study was conducted at Dow University of health sciences and Civil Hospital Karachi (DUHS & CHK Pakistan, designed to highlight the spectrum of perforation peritonitis in the East and to improve its outcome. Methods A prospective study includes three hundred consecutive patients of perforation peritonitis studied in terms of clinical presentations, Causes, site of perforation, surgical treatment, post operative complications and mortality, at (DUHS&CHK Pakistan, from 1st September 2005 – 1st March 2008, over a period of two and half years. All patients were resuscitated underwent emergency exploratory laparotomy. On laparotomy cause of perforation peritonitis was found and controlled. Results The most common cause of perforation peritonitis noticed in our series was acid peptic disease 45%, perforated duodenal ulcer (43.6% and gastric ulcer 1.3%. followed by small bowel tuberculosis (21% and typhoid (17%. large bowel perforation due to tuberculosis 5%, malignancy 2.6% and volvulus 0.3%. Perforation due to acute appendicitis (5%. Highest number of perforations has seen in the duodenum 43.6%, ileum37.6%, and colon 8%, appendix 5%, jejunum 3.3%, and stomach 2.3%. Overall mortality was (10.6%. Conclusion The spectrum of perforation peritonitis in Pakistan continuously differs from western country. Highest number of perforations noticed in the upper part of the gastrointestinal tract as compared to the western countries where the perforations seen mostly in the distal part. Most common cause of perforation peritonitis is perforated duodenal ulcer, followed by small bowel tuberculosis and typhoid perforation. Majority of the large bowel perforations are also tubercular

  3. Pseudo-random tool paths for CNC sub-aperture polishing and other applications.

    Science.gov (United States)

    Dunn, Christina R; Walker, David D

    2008-11-10

    In this paper we first contrast classical and CNC polishing techniques in regard to the repetitiveness of the machine motions. We then present a pseudo-random tool path for use with CNC sub-aperture polishing techniques and report polishing results from equivalent random and raster tool-paths. The random tool-path used - the unicursal random tool-path - employs a random seed to generate a pattern which never crosses itself. Because of this property, this tool-path is directly compatible with dwell time maps for corrective polishing. The tool-path can be used to polish any continuous area of any boundary shape, including surfaces with interior perforations.

  4. Differentiation of Acute Perforated from Non-Perforated Appendicitis: Usefulness of High-Resolution Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Gyu Chang [Dept. of Radiology, Gumi Hospital, Soonchunhyang University College of Medicine, Gumi (Korea, Republic of)

    2011-07-15

    To evaluate the usefulness of high-resolution ultrasonography (US) for the differentiation of acute perforated appendicitis from non-perforated appendicitis. The high-resolution US features in 96 patients (49 males, 47 females; mean age, 33.8 years; age range, 4-80 years) with pathologically proven acute appendicitis were evaluated. The following US findings were evaluated for differentiation of acute perforated appendicitis from non-perforated appendicitis: circumferential loss of the echogenic submucosal layer, periappendiceal fluid collection, disruption of the serosal layer, asymmetrical wall thickening, maximum overall diameter > 10.5 mm, and the presence of appendicoliths. The sensitivity and specificity of the US features in the diagnosis of acute perforated appendicitis were calculated. All of the US findings, except for appendicoliths, were significantly more common in the acute perforated appendicitis group (p < 0.001). The sensitivity of circumferential loss of the echogenic submucosal layer, periappendiceal fluid collection, disruption of the serosal layer, asymmetrical wall thickening, maximum overall diameter > 10.5 mm, and the presence of appendicoliths was 85.4, 73.2, 68.3, 70.7, 80.5, and 36.6%, respectively, while the specificity was 65.5, 89.1, 96.4, 98.2, 81.8, and 80.0%, respectively. High-resolution US was found to be useful for differentiating acute perforated appendicitis from non-perforated appendicitis.

  5. Gastrointestinal tract perforation: evaluation of MDCT according to perforation site and elapsed time

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Cheol; Yang, Dal Mo; Kim, Sang Won [Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Department of Radiology, Seoul (Korea, Republic of); Park, Seong Jin [Kyung Hee University Hospital, College of Medicine, Kyung Hee University, Department of Radiology, Seoul (Korea, Republic of)

    2014-06-15

    To evaluate mutidetector computed tomography (MDCT) for the prediction of perforation site according to each gastrointestinal (GI) tract site and elapsed time. One hundred and sixty-eight patients who underwent MDCT before laparotomy for GI tract perforation were enrolled and allocated to an early or late lapse group based on an elapsed time of 7 h. Two reviewers independently evaluated the perforation site and assessed the following CT findings: free air location, mottled extraluminal air bubbles, focal bowel wall discontinuity, segmental bowel wall thickening, perivisceral fat stranding and localised fluid collection. The overall diagnostic accuracy was 91.07 % and 91.67 % for reviewers 1 and 2, respectively, with excellent agreement (kappa 0.86). Accuracies (98.97 % and 97.94 %) and agreements (kappa 0.894) for stomach and duodenum perforation were higher than for other perforation sites. Strong predictors of perforation at each site were: focal bowel wall discontinuity for stomach, duodenal bulb and left colon, mottled extraluminal air bubbles for retroperitoneal duodenum and right colon, and segmental bowel wall thickening for small bowel. The diagnostic accuracy was not different between the early- and late-lapse groups. MDCT can accurately predict upper GI tract perforation with high reliability. Elapsed time did not affect the accuracy of perforation site prediction. (orig.)

  6. Coronary perforation and covered stents: An update and review

    Directory of Open Access Journals (Sweden)

    Mohammed Al-Mukhaini

    2011-01-01

    Full Text Available Coronary perforation is a rare complication of percutaneous coronary intervention. We present two different types of coronary intervention, but both ending with coronary perforation. However, these perforations were tackled successfully by covered stents. This article reviews the incidence, causes, presentation, and management of coronary perforation in the present era of aggressive interventional cardiology. Coronary perforations are classified as type I (extraluminal crater, II (myocardial or pericardial blushing, and III (contrast streaming or cavity spilling. Types I and II coronary perforations are caused by stiff or hydrophilic guidewires. Type I has a benign prognosis, whereas type II coronary perforations have the potential to progress to tamponade. Type III coronary perforations are caused by balloons, stents, or other intracoronary devices and commonly lead to cardiac tamponade necessitating pericardial drainage. However, type III perforations can be managed with covered stents without need for surgical intervention.

  7. Ischemic Preconditioning Mediates Neuroprotection against Ischemia in Mouse Hippocampal CA1 Neurons by Inducing Autophagy.

    Directory of Open Access Journals (Sweden)

    Chunlin Gao

    Full Text Available The hippocampal CA1 region is sensitive to hypoxic and ischemic injury but can be protected by ischemic preconditioning (IPC. However, the mechanism through which IPC protects hippocampal CA1 neurons is still under investigation. Additionally, the role of autophagy in determining the fate of hippocampal neurons is unclear. Here, we examined whether IPC induced autophagy to alleviate hippocampal CA1 neuronal death in vitro and in vivo with oxygen glucose deprivation (OGD and bilateral carotid artery occlusion (BCCAO models. Survival of hippocampal neurons increased from 51.5% ± 6.3% in the non-IPC group (55 min of OGD to 77.3% ± 7.9% in the IPC group (15 min of OGD, followed by 55 min of OGD 24 h later. The number of hippocampal CA1 layer neurons increased from 182 ± 26 cells/mm2 in the non-IPC group (20 min of BCCAO to 278 ± 55 cells/mm2 in the IPC group (1 min × 3 BCCAO, followed by 20 min of BCCAO 24 h later. Akt phosphorylation and microtubule-associated protein light chain 3 (LC3-II/LC3-I expression were increased in the preconditioning group. Moreover, the protective effects of IPC were abolished only by inhibiting the activity of autophagy, but not by blocking the activation of Akt in vitro. Using in vivo experiments, we found that LC3 expression was upregulated, accompanied by an increase in neuronal survival in hippocampal CA1 neurons in the preconditioning group. The neuroprotective effects of IPC on hippocampal CA1 neurons were completely inhibited by treatment with 3-MA. In contrast, hippocampal CA3 neurons did not show changes in autophagic activity or beneficial effects of IPC. These data suggested that IPC may attenuate ischemic injury in hippocampal CA1 neurons through induction of Akt-independent autophagy.

  8. Ischemic Preconditioning Mediates Neuroprotection against Ischemia in Mouse Hippocampal CA1 Neurons by Inducing Autophagy.

    Science.gov (United States)

    Gao, Chunlin; Cai, Ying; Zhang, Xuebin; Huang, Huiling; Wang, Jin; Wang, Yajing; Tong, Xiaoguang; Wang, Jinhuan; Wu, Jialing

    2015-01-01

    The hippocampal CA1 region is sensitive to hypoxic and ischemic injury but can be protected by ischemic preconditioning (IPC). However, the mechanism through which IPC protects hippocampal CA1 neurons is still under investigation. Additionally, the role of autophagy in determining the fate of hippocampal neurons is unclear. Here, we examined whether IPC induced autophagy to alleviate hippocampal CA1 neuronal death in vitro and in vivo with oxygen glucose deprivation (OGD) and bilateral carotid artery occlusion (BCCAO) models. Survival of hippocampal neurons increased from 51.5% ± 6.3% in the non-IPC group (55 min of OGD) to 77.3% ± 7.9% in the IPC group (15 min of OGD, followed by 55 min of OGD 24 h later). The number of hippocampal CA1 layer neurons increased from 182 ± 26 cells/mm2 in the non-IPC group (20 min of BCCAO) to 278 ± 55 cells/mm2 in the IPC group (1 min × 3 BCCAO, followed by 20 min of BCCAO 24 h later). Akt phosphorylation and microtubule-associated protein light chain 3 (LC3)-II/LC3-I expression were increased in the preconditioning group. Moreover, the protective effects of IPC were abolished only by inhibiting the activity of autophagy, but not by blocking the activation of Akt in vitro. Using in vivo experiments, we found that LC3 expression was upregulated, accompanied by an increase in neuronal survival in hippocampal CA1 neurons in the preconditioning group. The neuroprotective effects of IPC on hippocampal CA1 neurons were completely inhibited by treatment with 3-MA. In contrast, hippocampal CA3 neurons did not show changes in autophagic activity or beneficial effects of IPC. These data suggested that IPC may attenuate ischemic injury in hippocampal CA1 neurons through induction of Akt-independent autophagy.

  9. Case Report: Delayed Perforation after Definitive Treatment of Focal Intestinal Perforation with a Peritoneal Drain

    Directory of Open Access Journals (Sweden)

    Brian G. A. Dalton

    2012-01-01

    Full Text Available Focal intestinal perforation (FIP has long been described in the pediatric literature. Peritoneal drainage (PD is widely used as treatment for focal intestinal perforation. Here we report a premature infant that underwent PD on day of life 9 for a FIP. The infant recovered well from this episode and was discharged home without known sequelae. Subsequently, the same patient presented 16 months later with peritonitis. A perforation was discovered at laparotomy without evidence of surrounding necrosis. Given this finding, we believe this second episode of perforation was at the same site as the initial episode of FIP. The finding of FIP has been described without findings of surrounding necrosis. However, we believe this to be the first report of delayed perforation greater than 1 year from initial presentation after FIP treated definitively with peritoneal drain.

  10. Acquired perforating dermatosis in a patient with chronic renal failure*

    Science.gov (United States)

    Fernandes, Karen de Almeida Pinto; Lima, Lourenço de Azevedo; Guedes, Juliana Chaves Ruiz; Lima, Ricardo Barbosa; D'Acri, Antônio Macedo; Martins, Carlos José

    2016-01-01

    Perforating dermatoses are a group of skin diseases characterized by transepidermal elimination of dermal material. The disease is divided into two groups: the primary group and the secondary group. The classical or primary perforating dermatoses are subdivided into four types according to the eliminated dermal materials: Kyrle disease, perforating reactive collagenosis, elastosis perforans serpiginosa, and perforating folliculitis. The secondary form is known as acquired perforating dermatosis. The term was proposed in 1989 by Rapini to designate the perforating dermatoses affecting adult patients with systemic disease, regardless of the dermal materials eliminated. This report describes a case of the disease with elimination of collagen and elastic fibers in a patient with chronic renal failure.

  11. Suggesting a possible role of CA1 histaminergic system in harmane-induced amnesia.

    Science.gov (United States)

    Nasehi, Mohammad; Mashaghi, Elham; Khakpai, Fatemeh; Zarrindast, Mohammad-Reza

    2013-11-27

    A number of tremorogenic β-carboline alkaloids such as harmane are naturally present in the human food chain. They are derived from medicinal plants such as Peganum harmala that have been used as folk medicine in anticancer therapy. In the present study, effects of the histaminergic system of the dorsal hippocampus (CA1) on harmane-induced amnesia were examined. One-trial step-down was used to assess memory retention in adult male mice. The results showed that pre-training intra-CA1 administration of histamine (5μg/mouse), ranitidine (H2 receptor antagonist; at the doses of 0.25 and 0.5μg/mouse) and pyrilamine (H1 receptor antagonist; at the dose of 5μg/mouse) decreased memory formation. Pre-training intraperitoneal (i.p.) administration of harmane (12mg/kg) also decreased memory formation. Moreover, pre-training intra-CA1 injection of a sub-threshold dose of histamine (2.5μg/mouse) could reverse harmane (12mg/kg, i.p.)-induced impairment of memory. On the other hand, pre-training intra-CA1 injection of sub-threshold doses of ranitidine (0.0625μg/mouse) and pyrilamine (2.5μg/mouse) increased harmane-induced impairment of memory. In conclusion, the present findings suggest the involvement of the CA1 histaminergic system in harmane-induced impairment of memory formation.

  12. Surgical Treatment of Perforation Esophageal Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Depu Duan; Jihua Zou; Zhigang Cai; Shengyong Wu; Haibo Xiao; Yiyong Zhou; Xiang Liang; Dekui Sun; Songchang Wu

    2006-01-01

    OBJECTIVE To determine the ideal method of surgical preoperative treatment for perforation with esophageal carcinoma.METHODS 36 cases of perforation with esophageal carcinoma were treated surgically in this series.Perforations occurred into the right lung in14 cases ,the mediastinum in 17 cases and trachea in 5 cases.Open thoracic surgery was performed in 34 cases,in which the right thoracic approach using a 3-incision method was applied in 16 cases,and operation by stages in 15 cases.Of the 34 cases,retrosternal substitution of the esophagus with stomach or colon was performed in 26 cases.RESULTS Surgery was successful in 31 cases and operative death occurred in 3 cases.The postoperative follow up study was from 3~72months.Of these cases 15 wree alive at 7~12 months, 2 at 24 months,and 1 at 72 months. The results can be considered satisfactory.CONCLUSION The therapeutic results of surgical treatment of perforation with esophageal carcinoma were markedly superior to that of conventional conservative treatment. The authors suggest that surgical intervention without delay should be undertaken for patients having a perforation with carcinoma of the esophagus. A right thoracic approach with a 3-incision method (retrosternal replacement of esophagus with stomach or colon) or operation by stages is preferable.

  13. Contact lens rehabilitation following repaired corneal perforations

    Directory of Open Access Journals (Sweden)

    Sreenivas V

    2006-03-01

    Full Text Available Abstract Background Visual outcome following repair of post-traumatic corneal perforation may not be optimal due to presence of irregular keratometric astigmatism. We performed a study to evaluate and compare rigid gas permeable contact lens and spectacles in visual rehabilitation following perforating corneal injuries. Method Eyes that had undergone repair for corneal perforating injuries with or without lens aspiration were fitted rigid gas permeable contact lenses. The fitting pattern and the improvement in visual acuity by contact lens over spectacle correction were noted. Results Forty eyes of 40 patients that had undergone surgical repair of posttraumatic corneal perforations were fitted rigid gas permeable contact lenses for visual rehabilitation. Twenty-four eyes (60% required aphakic contact lenses. The best corrected visual acuity (BCVA of ≥ 6/18 in the snellen's acuity chart was seen in 10 (25% eyes with spectacle correction and 37 (92.5% eyes with the use of contact lens (p Conclusion Rigid gas permeable contact lenses are better means of rehabilitation in eyes that have an irregular cornea due to scars caused by perforating corneal injuries.

  14. Path Creation

    DEFF Research Database (Denmark)

    Karnøe, Peter; Garud, Raghu

    2012-01-01

    This paper employs path creation as a lens to follow the emergence of the Danish wind turbine cluster. Supplier competencies, regulations, user preferences and a market for wind power did not pre-exist; all had to emerge in a tranformative manner involving multiple actors and artefacts. Competenc......This paper employs path creation as a lens to follow the emergence of the Danish wind turbine cluster. Supplier competencies, regulations, user preferences and a market for wind power did not pre-exist; all had to emerge in a tranformative manner involving multiple actors and artefacts....... Competencies emerged through processes and mechanisms such as co-creation that implicated multiple learning processes. The process was not an orderly linear one as emergent contingencies influenced the learning processes. An implication is that public policy to catalyse clusters cannot be based...

  15. Membrane Potential Dynamics of CA1 Pyramidal Neurons during Hippocampal Ripples in Awake Mice.

    Science.gov (United States)

    Hulse, Brad K; Moreaux, Laurent C; Lubenov, Evgueniy V; Siapas, Athanassios G

    2016-02-17

    Ripples are high-frequency oscillations associated with population bursts in area CA1 of the hippocampus that play a prominent role in theories of memory consolidation. While spiking during ripples has been extensively studied, our understanding of the subthreshold behavior of hippocampal neurons during these events remains incomplete. Here, we combine in vivo whole-cell and multisite extracellular recordings to characterize the membrane potential dynamics of identified CA1 pyramidal neurons during ripples. We find that the subthreshold depolarization during ripples is uncorrelated with the net excitatory input to CA1, while the post-ripple hyperpolarization varies proportionately. This clarifies the circuit mechanism keeping most neurons silent during ripples. On a finer timescale, the phase delay between intracellular and extracellular ripple oscillations varies systematically with membrane potential. Such smoothly varying delays are inconsistent with models of intracellular ripple generation involving perisomatic inhibition alone. Instead, they suggest that ripple-frequency excitation leading inhibition shapes intracellular ripple oscillations.

  16. Postsynaptic blockade of inhibitory postsynaptic currents by plasmin in CA1 pyramidal cells of rat hippocampus.

    Science.gov (United States)

    Mizutani, A; Tanaka, T; Saito, H; Matsuki, N

    1997-06-27

    We have shown previously that plasmin facilitated the generation of long-term potentiation (LTP) in CA1 and dentate region of rat hippocampus. In the present study, we investigated the effects of plasmin on postsynaptic currents in CA1 pyramidal neurons of rat hippocampal slices. Plasmin (100 nM) had no effect on NMDA nor on non-NMDA receptor-mediated excitatory postsynaptic currents. However, plasmin significantly decreased GABA(A) receptor-mediated inhibitory postsynaptic currents. This effect of plasmin disappeared when intracellular Ca2+ was strongly chelated with BAPTA. Furthermore, plasmin attenuated the GABA-induced currents in CA1 pyramidal cells. These results suggest that the STP-enhancing effect of plasmin is due to a blockade of postsynaptic GABA(A) responses and that an increase in intracellular Ca2+ by plasmin may be involved in its mechanism.

  17. Traumatic Forefoot Reconstructions With Free Perforator Flaps.

    Science.gov (United States)

    Zhu, Yue-Liang; He, Xiao-Qing; Wang, Yi; Lv, Qian; Fan, Xin-Yv; Xu, Yong-Qing

    2015-01-01

    The forefoot is critical to normal walking; thus, any reconstruction of forefoot defects, including the soft tissues, must be carefully done. The free perforator flap, with its physiologic circulation, lower donor site morbidity, and minimal thickness is the most popular technique in plastic and microsurgery, and is theoretically the most suitable for such forefoot reconstruction. However, these flaps are generally recognized as more difficult and time-consuming to create than other flaps. In 41 patients with traumatic forefoot defects, we reconstructed the forefoot integument using 5 types of free perforator flaps. The overall functional and cosmetic outcomes were excellent. Three flaps required repeat exploration; one survived. The most common complications were insufficient perfusion and the need for second debulking. The key to our success was thoroughly debriding devitalized bone and soft tissue before attaching the flap. Forefoot reconstruction with a free perforator flap provides better function, better cosmesis, better weightbearing, and better gait than the other flaps we have used.

  18. Traumatic oesophageal perforation due to haematoma

    DEFF Research Database (Denmark)

    Grønhøj Larsen, Christian; Brandt, Bodil

    2014-01-01

    INTRODUCTION: Traumatic oesophageal perforation is a rare, life-threatening emergency that requires early recognition and prompt surgical management. PRESENTATION OF CASE: We present an unusual case of a patient on warfarin treatment developed an intramural oesophageal haematoma following blunt......; or the intramural hematoma gradually lysed and causing late perforation. CONCLUSION: Although extremely rare, an oesophageal haematoma and late complications must be considered in patients on anti-coagulant therapy following blunt thoracic trauma and complaining only of chest pain....... thoracic trauma leading to perforation on the 18th day. DISCUSSION: In treatment of oesophageal haematoma in patients on vitamin-K antagonists, strict control of the International Normalized Ratio (INR) is essential along with total parenteral nutrition therapy and refrainment through nasogastric tubes...

  19. Transient increase in Zn2+ in hippocampal CA1 pyramidal neurons causes reversible memory deficit.

    Directory of Open Access Journals (Sweden)

    Atsushi Takeda

    Full Text Available The translocation of synaptic Zn(2+ to the cytosolic compartment has been studied to understand Zn(2+ neurotoxicity in neurological diseases. However, it is unknown whether the moderate increase in Zn(2+ in the cytosolic compartment affects memory processing in the hippocampus. In the present study, the moderate increase in cytosolic Zn(2+ in the hippocampus was induced with clioquinol (CQ, a zinc ionophore. Zn(2+ delivery by Zn-CQ transiently attenuated CA1 long-term potentiation (LTP in hippocampal slices prepared 2 h after i.p. injection of Zn-CQ into rats, when intracellular Zn(2+ levels was transiently increased in the CA1 pyramidal cell layer, followed by object recognition memory deficit. Object recognition memory was transiently impaired 30 min after injection of ZnCl(2 into the CA1, but not after injection into the dentate gyrus that did not significantly increase intracellular Zn(2+ in the granule cell layer of the dentate gyrus. Object recognition memory deficit may be linked to the preferential increase in Zn(2+ and/or the preferential vulnerability to Zn(2+ in CA1 pyramidal neurons. In the case of the cytosolic increase in endogenous Zn(2+ in the CA1 induced by 100 mM KCl, furthermore, object recognition memory was also transiently impaired, while ameliorated by co-injection of CaEDTA to block the increase in cytosolic Zn(2+. The present study indicates that the transient increase in cytosolic Zn(2+ in CA1 pyramidal neurons reversibly impairs object recognition memory.

  20. EFFECTS OF GLUTAMATE ON SODIUM CHANNEL IN ACUTELY DISSOCIATED HIPPOCAMPAL CA1 PYRAMIDAL NEURONS OF RATS

    Institute of Scientific and Technical Information of China (English)

    高宾丽; 伍国锋; 杨艳; 刘智飞; 曾晓荣

    2011-01-01

    Objective To observe the effects of glutamate on sodium channel in acutely dissociated hippocampal CA1 pyramidal neurons of rats.Methods Voltage-dependent sodium currents (INa) in acutely dissociated hippocampal CA1 pyramidal neurons of neonate rats were recorded by whole-cell patchclamp of the brain slice technique when a series of doses of glutamate (100-1000μmol/L) were applied.Results Different concentrations of glutamate could inhibit INa,and higher concentration of glutamate affected greater inhibitio...

  1. Synthesis and spectroscopic characterization of Yb3+ in Ca1-XYbXF2+X crystals

    Science.gov (United States)

    Ito, M.; Goutaudier, C.; Guyot, Y.; Lebbou, K.; Fukuda, T.; Boulon, G.

    2004-11-01

    Ca1-XYbXF2+X crystals were grown by two different methods: simple melting under CF{4} atmosphere and laser heated pedestal growth (LHPG) method under Ar atmosphere. Spectroscopic characterization has been carried out to separate different crystallographic site in Ca1-XYbXF2+X crystals and to identify Stark's levels of Yb3+ transitions. Experimental decay time dependence of Yb3+ concentration was analyzed by using concentration gradient fiber in order to understand concentration quenching mechanisms. Energy transfer to unexpected rare earth impurities observed by up-conversion emission spectra in visible region under IR Yb3+ ion pumping seems to be an efficient process.

  2. Novel nootropic dipeptide Noopept increases inhibitory synaptic transmission in CA1 pyramidal cells.

    Science.gov (United States)

    Kondratenko, Rodion V; Derevyagin, Vladimir I; Skrebitsky, Vladimir G

    2010-05-31

    Effects of newly synthesized nootropic and anxiolytic dipeptide Noopept on inhibitory synaptic transmission in hippocampal CA1 pyramidal cells were investigated using patch-clamp technique in whole-cell configuration. Bath application of Noopept (1 microM) significantly increased the frequency of spike-dependant spontaneous IPSCs whereas spike-independent mIPSCs remained unchanged. It was suggested that Noopept mediates its effect due to the activation of inhibitory interneurons terminating on CA1 pyramidal cells. Results of current clamp recording of inhibitory interneurons residing in stratum radiatum confirmed this suggestion.

  3. Preoperative staging of perforated diverticulitis by computed tomography scanning

    NARCIS (Netherlands)

    M.P.M. Gielens; I.M. Mulder (Irene); E. van der Harst (Erwin); M.P. Gosselink (Martijn Pieter); K.J. Kraal; H.T. Teng; J.F. Lange (Johan); J. Vermeulen (Jefrey)

    2012-01-01

    textabstractBackground: Treatment of perforated diverticulitis depends on disease severity classified according to Hinchey's preoperative classification. This study assessed the accuracy of preoperative staging of perforated diverticulitis by computerized tomography (CT) scanning. Methods: All patie

  4. Pseudo-skin model for gravel-filled perforations

    Energy Technology Data Exchange (ETDEWEB)

    Onyekonwu, M.O. [Laser Engineering Consultants/Uniport, Port Harcourt (Nigeria); Okonkwo, F.C. [University of Port Harcourt Uniport, Port Harcourt (Nigeria)

    1997-11-05

    This paper discusses pressure losses due to flow in perforations filled with gravel or with formation material. These pressure losses are added to the pressure losses caused by convergence to perforations to obtain the pseudo-skin due to gravel-filled perforations. Calculation of the pressure loss due to convergence to perforation is discussed elsewhere. The flow in the perforation tunnel could be turbulent or laminar. Therefore, we calculated the pressure losses in a gravel-filled perforation using Forchheimer`s equation or Darcy`s law. However, we expect that the flow in such tunnels will be turbulent. Results from our model agree with experimental data published elsewhere. Also, our results show that pressure losses during flow through gravel-filled perforations could be substantial. Therefore, productivities of gravel pack completions may differ significantly from perforated completions in competent formation without gravel pack

  5. Duodenal Perforation Precipitated by Scrub Typhus.

    Science.gov (United States)

    Rajat, Raghunath; Deepu, David; Jonathan, Arul Jeevan; Prabhakar, Abhilash Kundavaram Paul

    2015-01-01

    Scrub typhus is an acute febrile illness usually presenting with fever, myalgia, headache, and a pathognomonic eschar. Severe infection may lead to multiple organ failure and death. Gastrointestinal tract involvement in the form of gastric mucosal erosions and ulcerations owing to vasculitis resulting in gastrointestinal bleeding is common. This process may worsen a pre-existent asymptomatic peptic ulcer, causing duodenal perforation, and present as an acute abdomen requiring surgical exploration. We report the case of a patient with no previous symptoms or risk factors for a duodenal ulcer, who presented with an acute duodenal perforation, probably precipitated by scrub typhus infection.

  6. Duodenal perforation precipitated by scrub typhus

    Directory of Open Access Journals (Sweden)

    Raghunath Rajat

    2015-01-01

    Full Text Available Scrub typhus is an acute febrile illness usually presenting with fever, myalgia, headache, and a pathognomonic eschar. Severe infection may lead to multiple organ failure and death. Gastrointestinal tract involvement in the form of gastric mucosal erosions and ulcerations owing to vasculitis resulting in gastrointestinal bleeding is common. This process may worsen a pre-existent asymptomatic peptic ulcer, causing duodenal perforation, and present as an acute abdomen requiring surgical exploration. We report the case of a patient with no previous symptoms or risk factors for a duodenal ulcer, who presented with an acute duodenal perforation, probably precipitated by scrub typhus infection.

  7. Right-Sided Sigmoid Diverticular Perforation

    Directory of Open Access Journals (Sweden)

    Andrew Little

    2012-04-01

    Full Text Available Diverticulosis is a common disorder among geriatric patients, of whom 10% to 25% go on to develop diverticulitis. Known complications of diverticulitis include formation of phlegmon, fistula, bowel obstruction, bleeding, perforation, and colonic abscess. A less common complication is perforation with formation of an extra-abdominal necrotizing abscess. This case is a report of an 83-year-old female who presented to the emergency department with a necrotizing abdominal wall abscess secondary to right-sided diverticular microperforation. [West J Emerg Med. 2012;13(1:103–105.

  8. Pneumoperitoneum Secondary to Spontaneously Perforated Pyometra

    Directory of Open Access Journals (Sweden)

    Benjamin A. Raymond

    2017-01-01

    Full Text Available Pyometra, by definition, is a collection of purulent fluid within the uterine cavity. Incidence has been estimated to range from 0.1% to 0.5%. Typically, this is linked to postmenopausal women; however, it has been linked to premenopausal women with concordant use of intrauterine devices. Based on our knowledge, there have been less than 50 recorded cases reported in the English literature regarding perforation of pyometra resulting in acute abdomen and fewer than 25 resulting in pneumoperitoneum. We report a patient who was evaluated for diffuse peritonitis caused by perforated pyometra who was successfully treated with surgical intervention.

  9. Perforated diverticulitis presenting as necrotising fasciitis of the leg

    Directory of Open Access Journals (Sweden)

    Talbot Robert

    2008-02-01

    Full Text Available Abstract Diverticulosis of the colon is a common condition of increasing age. Complications of diverticulitis including stricture, perforation and fistula formation often require surgery. Perforated diverticulitis may rarely present with spreading superficial sepsis. We describe for the first time, to our knowledge, a case of retroperitoneal diverticula perforation presenting as necrotising fasciitis of the leg necessitating hind-quarter amputation.

  10. Spontaneous perforation of a pyometra presenting as generalized peritonitis.

    Science.gov (United States)

    Hosking, S. W.

    1985-01-01

    Eleven cases of spontaneous perforation of a pyometra have previously been reported. All were associated with, and probably secondary to, cervical occlusion. A further case is described, but differs in that the cervical canal was patent. In the absence of other possible causes of uterine perforation, the aetiology of the perforation in this case remains uncertain. Images Figure 1 PMID:4040634

  11. Extended studies on the effect of glutamate antagonists on ischemic CA-1 damage

    DEFF Research Database (Denmark)

    Diemer, Nils Henrik; Balchen, T; Bruhn, T;

    1996-01-01

    Glutamate receptors are numerous on the ischemia vulnerable CA-1 pyramidal cells. Postischemic use of the AMPA antagonist NBQX has shown up to 80% protection against cell death. Three aspects of this were studied: In the first study, male Wistar rats were given NBQX (30 mg/kg x 3) either 20 hours...

  12. Circadian rhythm modulates long-term potentiation induced at CA1 in rat hippocampal slices.

    Science.gov (United States)

    Nakatsuka, Hiroki; Natsume, Kiyohisa

    2014-03-01

    Circadian rhythm affects neuronal plasticity. Consistent with this, some forms of synaptic long-term potentiation (LTP) are modulated by the light/dark cycle (LD cycle). For example, this type of modulation is observed in hippocampal slices. In rodents, which are nocturnal, LTP is usually facilitated in the dark phase, but the rat hippocampal CA1 is an exception. The reason why LTP in the dark phase is suppressed in CA1 remains unknown. Previously, LTP was induced with high-frequency stimulation. In this study, we found that in the dark phase, theta-burst stimulation-induced LTP is indeed facilitated in CA1, similar to other regions in the rodent brain. Population excitatory postsynaptic potentials (pEPSP)-LTP and population spikes (PS)-LTP were recorded at CA1. The magnitude of PS-LTP in dark-phase slices was significantly larger than in light-phase slices, while that of pEPSP-LTP was unchanged. Using antidromic-orthodromic stimulation, we found that recurrent inhibition is suppressed in the dark phase. Local gabazine-application to stratum pyramidale in light-phase slices mimicked this disinhibition and facilitated LTP in dark-phase slices. These results suggest that the disinhibition of a GABAA recurrent inhibitory network can be induced in the dark phase, thereby facilitating LTP.

  13. Electrical conductivity of the hippocampal CA1 layers and application to current-source-density analysis

    NARCIS (Netherlands)

    Holsheimer, J.

    1987-01-01

    The microstructure of the layers in the hippocampal CA1 area suggests that differences may exist between the electrical conductivities of these layers. In order to quantify these differences a sinusoidal current was applied to hippocampal slices in a bathing medium and potential differences were mea

  14. Dendrosomal nanocurcumin prevents morphine self-administration behavior in rats despite CA1 damage.

    Science.gov (United States)

    Norozi, Jalaleden; Hassanpour-Ezatti, Majid; Alaei, Hojjat A

    2017-01-25

    Dendrosomal nanocurcumin (DNC) is fabricated from esterification of oleic acid and polyethylene glycol residues with curcumin. DNC has shown antioxidant, neuroprotective, and neurogenesis-enhancing effects. In addition, it can attenuate morphine tolerance. Morphine self-administration is associated with neurodegenerative changes of CA1 neurons in the adult hippocampus. The present study evaluated the effect of DNC pretreatment on morphine self-administration and hippocampal damage. Rats were pretreated with DNC (5 and 10 mg/kg, intraperitoneally) 30 min before a morphine self-administration paradigm performed in 2-h/sessions for 12 days under a FR-1 schedule. Pretreatment with both doses of DNC markedly suppressed morphine intake. Morphine self-administration resulted in a 71% reduction in the number of hippocampal CA1 neurons. DNC (5 mg/kg) pretreatment only marginally improved (by 22%) neuronal loss in this area. The data suggest that the effect of DNC on morphine self-administration is largely independent of the CA1 area. A functional restoration and regulation of reward circuit activity by DNC may reduce the motivation for morphine despite CA1 damage.

  15. Parvalbumin-positive CA1 interneurons are required for spatial working but not for reference memory

    OpenAIRE

    Murray, Andrew J.; Sauer, Jonas-Frederic; Riedel, Gernot; McClure, Christina; Ansel, Laura; Cheyne, Lesley; Bartos, Marlene; Wisden, William; Wulff, Peer

    2011-01-01

    Parvalbumin-positive GABAergic interneurons in cortical circuits are hypothesized to control cognitive function. To test this idea directly, we functionally removed parvalbumin-positive interneurons selectively from hippocampal CA1 in mice. We found that parvalbumin-positive interneurons are dispensable for spatial reference, but are essential for spatial working memory.

  16. Parvalbumin-positive CA1 interneurons are required for spatial working but not for reference memory.

    Science.gov (United States)

    Murray, Andrew J; Sauer, Jonas-Frederic; Riedel, Gernot; McClure, Christina; Ansel, Laura; Cheyne, Lesley; Bartos, Marlene; Wisden, William; Wulff, Peer

    2011-03-01

    Parvalbumin-positive GABAergic interneurons in cortical circuits are hypothesized to control cognitive function. To test this idea directly, we functionally removed parvalbumin-positive interneurons selectively from hippocampal CA1 in mice. We found that parvalbumin-positive interneurons are dispensable for spatial reference, but are essential for spatial working memory.

  17. Distinguishing linear vs. nonlinear integration in CA1 radial oblique dendrites: it’s about time

    Directory of Open Access Journals (Sweden)

    José Francisco eGómez González

    2011-11-01

    Full Text Available It was recently shown that multiple excitatory inputs to CA1 pyramidal neuron dendrites must be activated nearly simultaneously to generate local dendritic spikes and superlinear responses at the soma; even slight input desynchronization prevented local spike initiation (Gasparini, 2006;Losonczy, 2006. This led to the conjecture that CA1 pyramidal neurons may only express their nonlinear integrative capabilities during the highly synchronized sharp waves and ripples that occur during slow wave sleep and resting/consummatory behavior, whereas during active exploration and REM sleep (theta rhythm, inadequate synchronization of excitation would lead CA1 pyramidal cells to function as essentially linear devices. Using a detailed single neuron model, we replicated the experimentally observed synchronization effect for brief inputs mimicking single synaptic release events. When synapses were driven instead by double pulses, more representative of the bursty inputs that occur in vivo, we found that the tolerance for input desynchronization was increased by more than an order of magnitude. The effect depended mainly on paired pulse facilitation of NMDA receptor-mediated responses at Schaffer collateral synapses. Our results suggest that CA1 pyramidal cells could function as nonlinear integrative units in all major hippocampal states.

  18. Determination of the Fundamental Frequency of Perforated Rectangular Plates: Concentrated Negative Mass Approach for the Perforation

    Directory of Open Access Journals (Sweden)

    Kiran D. Mali

    2013-01-01

    Full Text Available This paper is concerned with a vibration analysis of perforated rectangular plates with rectangular perforation pattern of circular holes. The study is particularly useful in the understanding of the vibration of sound absorbing screens, head plates, end covers, or supports for tube bundles typically including tube sheets and support plates used in the mechanical devices. An energy method is developed to obtain analytical frequencies of the perforated plates with clamped edge, support conditions. Perforated plate is considered as plate with uniformly distributed mass. Holes are considered as concentrated negative masses. The analytical procedure using the Galerkin method is adopted. The deflected surface of the plate is approximated by the cosine series which satisfies the boundary conditions. Finite element method (FEM results have been used to illustrate the validity of the analytical model. The comparisons show that the analytical model predicts natural frequencies reasonably well for holes of small size.

  19. Ischemia-induced degeneration of CA1 pyramidal cells decreases seizure severity in a subgroup of epileptic gerbils and affects parvalbumin immunoreactivity of CA1 interneurons.

    Science.gov (United States)

    Winkler, D T; Scotti, A L; Nitsch, C

    2001-04-01

    Mongolian gerbils are epilepsy-prone animals. In adult gerbils two major groups can be differentiated according to their seizure behavior: Highly seizure-sensitive gerbils exhibit facial and forelimb clonus or generalized tonic-clonic seizures from the first test on, while kindled-like gerbils are seizure free for the first three to six consecutive tests, later develop forelimb myoclonus, and eventually progress to generalized tonic-clonic seizures. In the hippocampus, seizure history of the individual animal is mirrored in the intensity in which GABAergic neurons are immunostained for the calcium-binding protein parvalbumin: they lose parvalbumin with increasing seizure incidence. In a first step to clarify the influence of hippocampal projection neurons on spontaneous seizure behavior and related parvalbumin expression, we induced degeneration of the CA1 pyramidal cells by transient forebrain ischemia. This results in a decreased seizure sensitivity in highly seizure-sensitive gerbils. The kindling-like process, however, is not permanently blocked by the ischemic nerve cell loss, suggesting that an intact CA1 field is not a prerequisite for the development of seizure behavior. The seizure-induced loss of parvalbumin from the ischemia-resistant interneurons recovers after ischemia. Thus, changes in parvalbumin content brought about by repeated seizures are not permanent but can rather be modulated by novel stimuli.

  20. Discriminating between simple and perforated appendicitis

    NARCIS (Netherlands)

    M. Bröker (Mirelle); E.M.M. van Lieshout (Esther); M. van der Elst (Maarten); L.P. Stassen (Laurents); T. Schepers (Tim)

    2012-01-01

    textabstractBackground: Several studies have been performed in order to diagnose an acute appendicitis using history taking and laboratory investigations. The aim of this study was to create a model for the identification of a perforated appendicitis. Methods: All consecutive patients who have under

  1. Infantile perforated appendicitis: A forgotten diagnosis

    Directory of Open Access Journals (Sweden)

    Katherine W. Gonzalez

    2015-04-01

    Full Text Available Acute appendicitis in the infant is a rare surgical diagnosis despite its frequency in older patients. The clinical presentation is often vague and can be misleading. We present the successful diagnosis and treatment of a 3 month old female with perforated appendicitis.

  2. Traumatic and nontraumatic perforation of hollow viscera.

    Science.gov (United States)

    Espinoza, R; Rodríguez, A

    1997-12-01

    Hollow viscus injuries are usually managed with few complications. However, if their diagnosis is delayed, or if reparative suture closure should fail, the patient is placed at risk of multiple organ failure. This article presents diagnostic approaches, emphasizing imaging modalities, and therapeutic strategies for three clinical scenarios of hollow viscus perforation: 1) acute appendicitis, 2) gastroduodenal peptic ulcer disease, and 3) trauma.

  3. Long-term survival after perforated diverticulitis

    NARCIS (Netherlands)

    J. Vermeulen (Jan); M.P. Gosselink (Martijn Pieter); W.C.J. Hop (Wim); E. van der Harst (Erwin); B.E. Hansen (Bettina); G.H.H. Mannaerts (Guido); P-P. Coene (Peter Paul); W.F. Weidema (Wibo); J.F. Lange (Johan)

    2011-01-01

    textabstractAim: Short-term survival after emergency surgery for perforated diverticulitis is poor. Less is known about long-term survival. The aims of this study were to evaluate long-term survival after discharge from hospital and to identify factors associated with prognosis. Method: All patients

  4. Jejunal Diverticular Perforation due to Enterolith

    Directory of Open Access Journals (Sweden)

    Ronaldo Nonose

    2011-08-01

    Full Text Available Jejunal diverticulosis is a rare entity with variable clinical and anatomical presentations. Although there is no consensus on the management of asymptomatic jejunal diverticular disease, some complications are potentially life-threatening and require early surgical treatment. Small bowel perforation secondary to jejunal diverticulitis by enteroliths is rare. The aim of this study was to report a case of small intestinal perforation caused by a large jejunal enterolith. An 86-year-old woman was admitted with signs of diffuse peritonitis. After initial fluid recovery the patient underwent emergency laparotomy. The surgery showed that she had small bowel diverticular disease, mainly localized in the proximal jejunum. The peritonitis was due to intestinal perforation caused by an enterolith 12 cm in length, localized inside one of these diverticula. The intestinal segment containing the perforated diverticulum with the enterolith was removed and an end-to-end anastomosis was done to reconstruct the intestinal transit. The patient recovered well and was discharged from hospital on the 5th postoperative day. There were no signs of abdominal pain 1 year after the surgical procedure. Although jejunal diverticular disease with its complications, such as formation of enteroliths, is difficult to suspect in patients with peritonitis, it should be considered as a possible source of abdominal infection in the elderly patient when more common diagnoses have been excluded.

  5. [Nineteenth century physicians against drum perforation].

    Science.gov (United States)

    Kierzek, A

    1995-01-01

    The trials of "organic" closure of drum perforation are described. The achievements of Adam Politzer, Hermann Schwartze, Joseph Gruber are presented. The first who used term "myringoplasty" was Emil Berthold. The "epochal" method of Wasilij Okuniew and achievements of Beniamin Gomperz are also depicted. The scientific activities of Polish otologists: Ludwik Guranowski and Rafai Spira were presented.

  6. Perforated stomach following the Heimlich maneuver.

    Science.gov (United States)

    Cowan, M; Bardole, J; Dlesk, A

    1987-03-01

    The use of infradiaphragmatic abdominal pressure for relief of airway obstruction caused by food was first described by Henry Heimlich in 1974. Since that time, several complications have been reported. We report a case of gastric perforation occurring in a choking victim following the application of the Heimlich maneuver.

  7. Spontaneous closure of traumatic tympanic membrane perforations

    DEFF Research Database (Denmark)

    Jellinge, Marlene Ersgaard; Kristensen, S.; Larsen, K

    2015-01-01

    BACKGROUND: The treatment of traumatic tympanic membrane perforations varies in different investigations, ranging from observation to early surgical repair. The present study aimed to focus on the closure rate and the closure time in a group of patients treated with a watchful waiting policy. MET...

  8. Advances in micro-perforated panel absorbers

    Institute of Scientific and Technical Information of China (English)

    LIU Ke; TIAN Jing; JIAO Fenglei; L(U) Yadong

    2006-01-01

    Theoretical and experimental investigations on the performance of micro-perforated-panel absorbers are reviewed in this paper. By reviewing recent research work, this paper reveals a relationship between the maximum absorption coefficient and the limit of the absorption frequency bandwidth. It has been demonstrated that the absorption frequency bandwidth can be extended up to 3 or 4 octaves as the diameters of the micro-holes decrease. This has become possible with the development of the technologies for manufacturing micro-perforated panels,such as laser drilling, powder metallurgy, welded meshing and electro-etching to form micrometer order holes. In this paper, absorption characteristics of such absorbers in random fields and in high sound intensity are discussed both theoretically and experimentally. A new absorbing structure based on micro-perforated-panel absorbers demonstrate experimentally high sound absorption capability. This review shows that the micro-perforated-panel absorber has potentials to be one of ideal absorbing materials in the 21st century.

  9. Acute phlegmonous gastritis complicated by delayed perforation.

    Science.gov (United States)

    Min, Sun Young; Kim, Yong Ho; Park, Won Seo

    2014-03-28

    Here, we report on a case of acute phlegmonous gastritis (PG) complicated by delayed perforation. A 51-year-old woman presented with severe abdominal pain and septic shock symptoms. A computed tomography scan showed diffuse thickening of the gastric wall and distention with peritoneal fluid. Although we did not find definite evidence of free air on the computed tomography (CT) scan, the patient's clinical condition suggested diffuse peritonitis requiring surgical intervention. Exploratory laparotomy revealed a thickened gastric wall with suppurative intraperitoneal fluid in which Streptococcus pyogenes grew. There was no evidence of gastric or duodenal perforation. No further operation was performed at that time. The patient was conservatively treated with antibiotics and proton pump inhibitor, and her condition improved. However, she experienced abdominal and flank pain again on postoperative day 10. CT and esophagogastroduodenoscopy showed a large gastric ulcer with perforation. Unfortunately, although the CT showed further improvement in the thickening of the stomach and the mucosal defect, the patient's condition did not recover until a week later, and an esophagogastroduodenoscopy taken on postoperative day 30 showed suspected gastric submucosal dissection. We performed total gastrectomy as a second operation, and the patient recovered without major complications. A pathological examination revealed a multifocal ulceration and necrosis from the mucosa to the serosa with perforation.

  10. Intestinal perforation caused by multiple magnet ingestion

    Directory of Open Access Journals (Sweden)

    Nergul Corduk

    2014-01-01

    Full Text Available Multiple magnet ingestion is rare, but can cause serious gastrointestinal complications. We report a case of 7-year-old girl with multiple intestinal perforations caused by multiple magnet ingestion. The aim of this report is to draw attention to magnetic toys, results of magnet ingestion and the importance of timing of operation.

  11. [Small bowel perforation caused by magnetic toys].

    Science.gov (United States)

    Schroepfer, E; Siauw, C; Hoecht, B; Meyer, T

    2010-06-01

    Accidental ingestion of foreign bodies is a common problem in infants and childhood, but ingestion of magnetic construction toys is very rare. In the case of ingestion of multiple parts of these magnetic construction toys, they may attract each other through the intestinal walls, causing pressure necrosis, perforation, fistula formation or intestinal obstruction. A 20-month-old boy presented with a three-day history of abdominal pain and bilious vomiting. Physical examination revealed a slighted distended abdomen. The -white blood cell count was increased, but the C-reactive protein was normal. Ultrasound and X-ray of the abdomen showed a distended bowel loop in the right upper quadrant, a moderate amount of free intraperitoneal liquid and 4 foreign bodies. Emergency laparotomy was performed and 2 perforations in the ileum were detected. The perforations were caused by a magnetic construction toy and 2 iron globes. The fourth foreign body was a glass marble. The foreign bodies were removed, both perforations were primarily sutured. The child was discharged on postoperative day 10 after an uneventful recovery. Parents should be warned against the potential dangers of children's constructions toys that contain these kinds of magnets.

  12. The one-stage rhinoplasty septal perforation repair.

    Science.gov (United States)

    Foda, H M

    1999-08-01

    A combined septal perforation repair and rhinoplasty was performed in 20 patients (12 males, eight females; age range 16-36, mean age 29.6) presenting with septal perforations (size 1-4 cm) and external nasal deformities. The external rhinoplasty approach was used for all cases and the perforation was repaired using bilateral intranasal mucosal advancement flaps with a connective tissue interposition graft in between. The perforation was totally closed in 18 cases (90 per cent) with complete resolution of the pre-operative symptoms occurring in 16 (80 per cent). Cosmetically, 19 cases (95 per cent) were very satisfied with their aesthetic result. The exposure provided by the external approach proved to be very helpful in the process of septal perforation repair. Our results show that septal perforation repair could safely be combined with rhinoplasty and that some of the rhinoplasty manoeuvres used could even facilitate the process of septal perforation repair.

  13. Multiple, Pan-Enteric Perforation Secondary to Intestinal Tuberculosis

    Directory of Open Access Journals (Sweden)

    Irfan Masood

    2015-01-01

    Full Text Available Free perforation is one of the most feared complications of the intestinal tuberculosis. The terminal ileum is the most common site of perforation, while the majority of (90% perforations are solitary. Herein, we describe a case of a 25-year-old male who presented with generalized peritonitis requiring an emergency exploratory laparotomy, which revealed pan-enteric perforation characterized by multiple perforations of the small bowel extending 10–15 cm from the DJ flexure up to the terminal ileum. The perforations were primarily closed, while 6–8 cm of the diseased terminal ileum was resected and the two ends were brought out as double-barreled ostomy. To the best of our knowledge, such an extensive tuberculous perforation of the small bowel has not been previously reported in the literature before.

  14. Multiple, Pan-Enteric Perforation Secondary to Intestinal Tuberculosis

    Science.gov (United States)

    Masood, Irfan; Majid, Zain; Rafiq, Ali; Rind, Waqas; Zia, Aisha; Raza, Sajjad

    2015-01-01

    Free perforation is one of the most feared complications of the intestinal tuberculosis. The terminal ileum is the most common site of perforation, while the majority of (90%) perforations are solitary. Herein, we describe a case of a 25-year-old male who presented with generalized peritonitis requiring an emergency exploratory laparotomy, which revealed pan-enteric perforation characterized by multiple perforations of the small bowel extending 10–15 cm from the DJ flexure up to the terminal ileum. The perforations were primarily closed, while 6–8 cm of the diseased terminal ileum was resected and the two ends were brought out as double-barreled ostomy. To the best of our knowledge, such an extensive tuberculous perforation of the small bowel has not been previously reported in the literature before. PMID:26798540

  15. The "Gent" consensus on perforator flap terminology: preliminary definitions.

    Science.gov (United States)

    Blondeel, Phillip N; Van Landuyt, Koen H I; Monstrey, Stan J M; Hamdi, Moustapha; Matton, Guido E; Allen, Robert J; Dupin, Charles; Feller, Axel-Mario; Koshima, Isao; Kostakoglu, Naci; Wei, Fu-Chan

    2003-10-01

    Due to its increasing popularity, more and more articles on the use of perforator flaps have been reported in the literature during the past few years. Because the area of perforator flaps is new and rapidly evolving, there are no definitions and standard rules on terminology and nomenclature, which creates confusion when surgeons try to communicate and compare surgical techniques. This article attempts to represent the opinion of a group of pioneers in the field of perforator flap surgery. This consensus was reached after a terminology consensus meeting held during the Fifth International Course on Perforator Flaps in Gent, Belgium, on September 29, 2001. It stipulates not only the definitions of perforator vessels and perforator flaps but also the correct nomenclature for different perforator flaps. The authors believe that this consensus is a foundation that will stimulate further discussion and encourage further refinements in the future.

  16. Layer selective presynaptic modulation of excitatory inputs to hippocampal CA1 by μ-opioid receptor activation

    OpenAIRE

    McQuiston, A. Rory

    2007-01-01

    Chronic and acute activation of μ-opioid receptors (MOR) in hippocampal CA1 disrupts rhythmic activity, alters activity-dependent synaptic plasticity and impairs spatial memory formation. In CA1, MORs act by hyperpolarizing inhibitory interneurons and suppressing inhibitory synaptic transmission. MOR modulation of inhibitory synaptic function translates into an increase in excitatory activity in all layers of CA1. However, the exact anatomical sites for MOR actions are not completely known. T...

  17. Feedforward inhibition underlies the propagation of cholinergically induced gamma oscillations from hippocampal CA3 to CA1.

    Science.gov (United States)

    Zemankovics, Rita; Veres, Judit M; Oren, Iris; Hájos, Norbert

    2013-07-24

    Gamma frequency (30-80 Hz) oscillations are implicated in memory processing. Such rhythmic activity can be generated intrinsically in the CA3 region of the hippocampus from where it can propagate to the CA1 area. To uncover the synaptic mechanisms underlying the intrahippocampal spread of gamma oscillations, we recorded local field potentials, as well as action potentials and synaptic currents in anatomically identified CA1 and CA3 neurons during carbachol-induced gamma oscillations in mouse hippocampal slices. The firing of the vast majority of CA1 neurons and all CA3 neurons was phase-coupled to the oscillations recorded in the stratum pyramidale of the CA1 region. The predominant synaptic input to CA1 interneurons was excitatory, and their discharge followed the firing of CA3 pyramidal cells at a latency indicative of monosynaptic connections. Correlation analysis of the input-output characteristics of the neurons and local pharmacological block of inhibition both agree with a model in which glutamatergic CA3 input controls the firing of CA1 interneurons, with local pyramidal cell activity having a minimal role. The firing of phase-coupled CA1 pyramidal cells was controlled principally by their inhibitory inputs, which dominated over excitation. Our results indicate that the synchronous firing of CA3 pyramidal cells rhythmically recruits CA1 interneurons and that this feedforward inhibition generates the oscillatory activity in CA1. These findings identify distinct synaptic mechanisms underlying the generation of gamma frequency oscillations in neighboring hippocampal subregions.

  18. Traumatic tympanic membrane perforation: An overview

    Directory of Open Access Journals (Sweden)

    Asef Wani

    2016-01-01

    Full Text Available Objectives: The purpose of this study was to determine the various etiologies of traumatic tympanic membrane (TM perforations; their clinical presentation, observation and establish masterly inactivity as the main modality of management. Materials and Methods: A prospective study was performed on 350 cases of traumatic TM perforation in the Department of ENT, SKIMS Medical College, Srinagar from January 2010 to December 2014. Results: A total of 350 patients with the traumatic TM. Perforation was enrolled for this study. The group consisted of 231 male and 119 female patients. It affects all age groups with the highest incidence among middle age group. The right ear was involved in 94 (26.85% patients, the left ear in 249 (71.14% patients and bilateral ear involvement was seen in 7 (2% patients. The type of trauma included compression injury in 243 (64.42% patients, instrumental injury in 88 (25.14% patients, and blast injury in 19 (5.42% patients. Tinnitus was the most common complaint, followed by aural fullness, impaired hearing, otalgia, bleeding from ear and vertigo. 217 (62% patients presented with conductive hearing loss in the range of 20–35 dB, 77 (22% patients with 35 dB hearing loss, and 28 (8% patients presented with no air-bone gap. Grade I perforation (50% TM involvement was present in 38 (10.90% patients. Complete healing was observed within 2–6 weeks in 172 (49.10% patients and within 7–9 weeks in 112 (32.20% patients. 35 (10% patients showed complete healing within 10–12 weeks. The minimum time taken to heal was 21 days and maximum time 72 days. Complete healing was observed in 319 (91.10% patients. The intervention was only performed when spontaneous healing failed to occur after observing the patients for 1 week and included tympanoplasty in 8 (2.30% patients, trichloroacetic acid cauterization in 14 (4% patients. Residual perforation was observed in 9 (2.5% patients. Conclusion: In our experience, traumatic TM

  19. Effects of electromagnetic radiation on spatial memory and synapses in rat hippocampal CA1

    Institute of Scientific and Technical Information of China (English)

    Yuhong Li; Changhua Shi; Guobing Lu; Qian Xu; Shaochen Liu

    2012-01-01

    In this study, we investigated the effects of mobile phone radiation on spatial learning, reference memory, and morphology in related brain regions. After the near-field radiation (0.52-1.08 W/kg) was delivered to 8-week-old Wistar rats 2 hours per day for 1 month, behavioral changes were examined using the Morris water maze. Compared with the sham-irradiated rats, the irradiated rats exhibited impaired performance. Morphological changes were investigated by examining synaptic ultrastructural changes in the hippocampus. Using the physical dissector technique, the number of pyramidal neurons, the synaptic profiles, and the length of postsynaptic densities in the CA1 region were quantified stereologically. The morphological changes included mitochondrial degenerations, fewer synapses, and shorter postsynaptic densities in the radiated rats. These findings indicate that mobile phone radiation can significantly impair spatial learning and reference memory and induce morphological changes in the hippocampal CA1 region.

  20. Caffeine and REM sleep deprivation: Effect on basal levels of signaling molecules in area CA1.

    Science.gov (United States)

    Alkadhi, Karim A; Alhaider, Ibrahim A

    2016-03-01

    We have investigated the neuroprotective effect of chronic caffeine treatment on basal levels of memory-related signaling molecules in area CA1 of sleep-deprived rats. Animals in the caffeine groups were treated with caffeine in drinking water (0.3g/l) for four weeks before they were REM sleep-deprived for 24h in the Modified Multiple Platforms paradigm. Western blot analysis of basal protein levels of plasticity- and memory-related signaling molecules in hippocampal area CA1 showed significant down regulation of the basal levels of phosphorylated- and total-CaMKII, phosphorylated- and total-CREB as well as those of BDNF and CaMKIV in sleep deprived rats. All these changes were completely prevented in rats that chronically consumed caffeine. The present findings suggest an important neuroprotective property of caffeine in sleep deprivation.

  1. Effects of carnosine on the evoked potentials in hippocampal CA1 region

    Institute of Scientific and Technical Information of China (English)

    Zhou-yan FENG; Xiao-jing ZHENG; Jing WANG

    2009-01-01

    Objective: To directly examine the effects of carnosine on neuronal excitation and inhibition in rat hippocampus in vivo. Methods: Artificial cerebrospinal fluid with carnosine was directly administrated over the exposed rat hippocampus. The changes of neuron activity in the CA1 region of hippocampus were evaluated by orthodromically- and antidromically-evoked potentials, as well as paired-pulse stimulation paradigm. Results: In both orthodromic and antidromic response potentials, carnosine transformed population spikes (PSs) with single spike into epileptiform multiple spikes. In addition, similar to the effect of γ-aminobutyric acidA (GABAA) antagonist picrotoxin, carnosine decreased paired-pulse stimulating depression significantly.However, no significant change was observed in the spontaneous field potentials during the application of carnosine. Conclusion:The results indicate a disinhibition-induced excitation effect of carnosine on the CA1 pyramidal neurons. It provides important information against the application of carnosine as a potential anticonvulsant in clinical treatment.

  2. Highly expressed genes within hippocampal sector CA1: implications for the physiology of memory

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    Michael A. Meyer

    2014-06-01

    Full Text Available As the CA1 sector has been implicated to play a key role in memory formation, a dedicated search for highly expressed genes within this region was made from an on-line atlas of gene expression within the mouse brain (GENSAT. From a data base of 1013 genes, 16 were identified that had selective localization of gene expression within the CA1 region, and included Angpt2, ARHGEF6, CCK, Cntnap1, DRD3, EMP1, Epha2, Itm2b, Lrrtm2, Mdk, PNMT, Ppm1e, Ppp2r2d, RASGRP1, Slitrk5, and Sstr4. Of the 16 identified, the most selective and intense localization for both adult and post-natal day 7 was noted for ARHGEF6, which is known to be linked to non-syndromic mental retardation, and has also been localized to dendritic spines. Further research on the role played by ARHGEF6 in memory formation is strongly advocated.

  3. Entorhinal theta-frequency input to the dentate gyrus trisynaptically evokes hippocampal CA1 LTP

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    Jens eStepan

    2012-09-01

    Full Text Available There exists substantial evidence that some forms of explicit learning in mammals require long-term potentiation (LTP at hippocampal CA3-CA1 synapses. While CA1 LTP has been well characterized at the monosynaptic level, it still remains unclear how the afferent systems to the hippocampus can initiate formation of this neuroplastic phenomenon. Using voltage-sensitive dye imaging in a mouse brain slice preparation, we show that evoked entorhinal cortical (EC theta-frequency input to the dentate gyrus highly effectively generates waves of neuronal activity which propagate through the entire trisynaptic circuit of the hippocampus (‘HTC-Waves’. This flow of activity, which we also demonstrate in vivo, critically depends on frequency facilitation of mossy fiber to CA3 synaptic transmission. The HTC-Waves are rapidly boosted by the cognitive enhancer caffeine (5 µM and the stress hormone corticosterone (100 nM. They precisely follow the rhythm of the EC input, involve high-frequency firing (>100 Hz of CA3 pyramidal neurons, and induce NMDA receptor-dependent CA1 LTP within a few seconds. Our study provides the first experimental evidence that synchronous theta-rhythmical spiking of EC stellate cells, as occurring during EC theta oscillations, has the capacity to drive induction of CA1 LTP via the hippocampal trisynaptic pathway. Moreover, we present data pointing to a basic filter mechanism of the hippocampus regarding EC inputs and describe a methodology to reveal alterations in the ‘input-output relationship’ of the hippocampal trisynaptic circuit.

  4. Protective roles of heat stress on the neurons in hippocampal CA1 region of mice

    Institute of Scientific and Technical Information of China (English)

    WANG Chunxu; WANG Hanxing

    2007-01-01

    The effects of heat stress on the neurons in hippocampal CA1 region of brain ischemia/reperfusion were explored.The mice were pretreated with heat stress followed by ischemia/reperfusion by clipping bilateral cervical common arteries for 7 min.Mice were divided randomly into four groups as follows:(1)normal control group;(2)heat stress pretreated subsequent to ischemia/reperfusion group (HS/IR);(3)ischemia/reperfusion group(IR);and(4)heat stress group(HS).Animals in the last three groups were subdivided into three subgroups:1 d,4 d,14 d respectively.The Morris water maze was used to test the ability of learning and memorizing,Nissl staining was used to count the average number of survived neurons in hippocampal CA1 region,and immunohistochemistry combined with image analysis system to detect the changes of Microtubule associated protein 2 (MAP-2)expression.The results showed that mice in IR group exhibited increased escape latency when compared with that of normal,HS and HS/IR groups(P<0.01),and the mice in IR group adopted an inefficient search strategy,major in circling and restricted searching manners.Nissl staining results showed a significant reduction in the number of pyramidal neurons in hippocampal CA1 regions in HS/IR and IR groups,with a decrease in IR group(P<0.01).Compared with normal group,the expression of MAP-2 in hippocampal CA1 region obviously decreased in IR group(P<0.05).The present results indicate that heat stress pretreatment can improve the spatial learning and memorizing function through protection to hippocampal neurons.

  5. Progressive alterations of hippocampal CA3-CA1 synapses in an animal model of depression.

    Science.gov (United States)

    Qiao, Hui; An, Shu-Cheng; Ren, Wei; Ma, Xin-Ming

    2014-12-15

    Major depressive disorder is the most prevalent psychiatric condition, but the cellular and molecular mechanisms underlying this disorder are largely unknown, although multiple hypotheses have been proposed. The aim of this study was to characterize the progressive alteration of neuronal plasticity in the male rat hippocampus during depression induced by chronic unpredictable mild stress (CUMS), an established animal model of depression. The data in the hippocampus were collected on days 7, 14 and 21 after the onset of three-week CUMS. When analyzed on day 21, three-week CUMS induced typically depressive-like behaviors, impaired LTP induction, and decreased basal synaptic transmission at hippocampal CA3-CA1 synapses recorded in vivo, which was accompanied by decreased density of dendritic spines in CA1 and CA3 pyramidal neurons. The levels of both Kalirin-7 and brain-derived neurotrophic factor (BDNF) in the hippocampus were decreased at the same time. On day 14 (middle phase), some depressive-like behaviors were observed, which was accompanied by depressed basal synaptic transmission and enhanced LTP induction at the CA3-CA1 synapses. However, BDNF expression was decreased without alteration of Kalirin7 expression in comparison with no-stress control. Depressed basal synaptic transmission occurred in the middle phase of CUMS may contribute to decreased expression of BDNF. On day 7, depressive-like behaviors were not observed, and LTP induction, spine density, Kalirin-7 and BDNF expression were not altered by CUMS in comparison with no-stress control. These results showed that the functional changes at CA3-CA1synapses occurred earlier than the structural alteration during three-week CUMS as a strategy of neural adaptation, and rats required three weeks to develop depressive-like behaviors during CUMS. Our results suggest an important role of Kalirin-7 in CUMS-mediated alterations in spine density, synaptic function and overall depressive-like behaviors on day 21.

  6. Encoding and retrieval in a model of the hippocampal CA1 microcircuit.

    Science.gov (United States)

    Cutsuridis, Vassilis; Cobb, Stuart; Graham, Bruce P

    2010-03-01

    It has been proposed that the hippocampal theta rhythm (4-7 Hz) can contribute to memory formation by separating encoding (storage) and retrieval of memories into different functional half-cycles (Hasselmo et al. (2002) Neural Comput 14:793-817). We investigate, via computer simulations, the biophysical mechanisms by which storage and recall of spatio-temporal input patterns are achieved by the CA1 microcircuitry. A model of the CA1 microcircuit is presented that uses biophysical representations of the major cell types, including pyramidal (P) cells and four types of inhibitory interneurons: basket (B) cells, axo-axonic (AA) cells, bistratified (BS) cells and oriens lacunosum-moleculare (OLM) cells. Inputs to the network come from the entorhinal cortex (EC), the CA3 Schaffer collaterals and medial septum. The EC input provides the sensory information, whereas all other inputs provide context and timing information. Septal input provides timing information for phasing storage and recall. Storage is accomplished via a local STDP mediated hetero-association of the EC input pattern and the incoming CA3 input pattern on the CA1 pyramidal cell target synapses. The model simulates the timing of firing of different hippocampal cell types relative to the theta rhythm in anesthetized animals and proposes experimentally confirmed functional roles for the different classes of inhibitory interneurons in the storage and recall cycles (Klausberger et al., (2003, 2004) Nature 421:844-848, Nat Neurosci 7:41-47). Measures of recall performance of new and previously stored input patterns in the presence or absence of various inhibitory interneurons are employed to quantitatively test the performance of our model. Finally, the mean recall quality of the CA1 microcircuit is tested as the number of stored patterns is increased.

  7. Exercise preconditioning exhibits neuroprotective effects on hippocampal CA1 neuronal damage after cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Nabi Shamsaei; Mehdi Khaksari; Sohaila Erfani; Hamid Rajabi; Nahid Aboutaleb

    2015-01-01

    Recent evidence has suggested the neuroprotective effects of physical exercise on cerebral isch-emic injury. However, the role of physical exercise in cerebral ischemia-induced hippocampal damage remains controversial. The aim of the present study was to evaluate the effects of pre-ischemia treadmill training on hippocampal CA1 neuronal damage after cerebral ischemia. Male adult rats were randomly divided into control, ischemia and exercise + ischemia groups. In the exercise + ischemia group, rats were subjected to running on a treadmill in a designated time schedule (5 days per week for 4 weeks). Then rats underwent cerebral ischemia induction th rough occlusion of common carotids followed by reperfusion. At 4 days after cerebral ischemia, rat learning and memory abilities were evaluated using passive avoidance memory test and rat hippocampal neuronal damage was detected using Nissl and TUNEL staining. Pre-ischemic ex-ercise signiifcantly reduced the number of TUNEL-positive cells and necrotic cell death in the hippocampal CA1 region as compared to the ischemia group. Moreover, pre-ischemic exercise significantly prevented ischemia-induced memory dysfunction. Pre-ischemic exercise mighct prevent memory deficits after cerebral ischemia through rescuing hippocampal CA1 neurons from ischemia-induced degeneration.

  8. Augmented inhibition from cannabinoid sensitive interneurons diminishes CA1 output after traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Brian Neal Johnson

    2014-12-01

    Full Text Available The neurological impairments associated with traumatic brain injury include learning and memory deficits and increased risk of seizures. The hippocampus is critically involved in both of these phenomena and highly susceptible to damage by traumatic brain injury. To examine network activity in the hippocampal CA1 region after lateral fluid percussion injury, we used a combination of voltage sensitive dye, field potential and patch clamp recording in mouse hippocampal brain slices. When the stratum radiatum was stimulated in slices from injured mice we found decreased depolarization in stratum radiatum and increased hyperpolarization in stratum oriens, together with a decrease in the percentage of pyramidal neurons firing stimulus-evoked action potentials. Increased hyperpolarization in stratum oriens persisted when glutamatergic transmission was blocked. However, we found no changes in stratum oriens responses when the alveus was stimulated to directly activate stratum oriens. These results suggest that the increased stratum oriens hyperpolarization evoked by stratum radiatum stimulation was mediated by interneurons that have cell bodies and/or axons in stratum radiatum, and form synapses in stratum pyramidale and stratum oriens. A low concentration (100 nM of the synthetic cannabinoid WIN55,212-2,restored CA1 output in slices from injured animals. These findings support the hypothesis that increased GABAergic signaling by cannabinoid sensitive interneurons contributes to the reduced CA1 output following traumatic brain injury.

  9. Thrombin modulates persistent sodium current in CA1 pyramidal neurons of young and adult rat hippocampus.

    Science.gov (United States)

    Lunko, O O; Isaev, D S; Krishtal, O O; Isaeva, E V

    2015-01-01

    Serine protease thrombin, a key factor of blood coagulation, participates in many neuronal processes important for normal brain functioning and during pathological conditions involving abnormal neuronal synchronization, neurodegeneration and inflammation. Our previous study on CA3 pyramidal neurons showed that application ofthrombin through the activation of specific protease-activated receptor 1 (PAR1) produces a significant hyperpolarizing shift of the activation of the TTX-sensitive persistent voltage-gated Na+ current (I(Nap)) thereby affecting membrane potential and seizure threshold at the network level. It was shown that PAR1 is also expressed in CA1 area of hippocampus and can be implicated in neuronal damage in this area after status epilepticus. The aim of the present study was to evaluate the effect of thrombin on I(NaP) in CA1 pyramidal neurons from adult and young rats. Using whole cell patch-clamp technique we demonstrate that thrombin application results in the hyperpolarization shift of I(NaP) activation as well as increase in the I(NaP) amplitude in both age groups. We have found that I(NaP) in pyramidal neurons of hippocampal CA 1 region is more vulnerable to the thrombin action than I(NaP) in pyramidal neurons of hippocampal CA3 region. We have also found that the immature hippocampus is more sensitive to thrombin action which emphasizes the contribution of thrombin-dependent pathway to the regulation of neuronal activity in immature brain.

  10. Vector Symbolic Spiking Neural Network Model of Hippocampal Subarea CA1 Novelty Detection Functionality.

    Science.gov (United States)

    Agerskov, Claus

    2016-04-01

    A neural network model is presented of novelty detection in the CA1 subdomain of the hippocampal formation from the perspective of information flow. This computational model is restricted on several levels by both anatomical information about hippocampal circuitry and behavioral data from studies done in rats. Several studies report that the CA1 area broadcasts a generalized novelty signal in response to changes in the environment. Using the neural engineering framework developed by Eliasmith et al., a spiking neural network architecture is created that is able to compare high-dimensional vectors, symbolizing semantic information, according to the semantic pointer hypothesis. This model then computes the similarity between the vectors, as both direct inputs and a recalled memory from a long-term memory network by performing the dot-product operation in a novelty neural network architecture. The developed CA1 model agrees with available neuroanatomical data, as well as the presented behavioral data, and so it is a biologically realistic model of novelty detection in the hippocampus, which can provide a feasible explanation for experimentally observed dynamics.

  11. Regulation of Astroglia on Synaptic Plasticity in the CA1 Region of Rat Hippocampus

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The regulation of astroglia on synaptic plasticity in the CA1 region of rat hippocampus was examined. Rats were divided into three groups: the newly born (<24 h), the juvenile (28-30days) and the adult groups (90-100 days), with each group having 20 animals. The CA1 region of rat hippocampus was immunohistochemically and electron-microscopically examined, respectively,for the growth of astroglia and the ultrastructure of synapses. The high performance liquid chromatography was employed to determine the cholesterol content of rat hippocampus. In the newly-born rats, a large number of neurons were noted in the hippocampal CA1 region of the newly-born rats,and few astroglia and no synaptic structure were observed. In the juvenile group, a few astroglias and some immature synapses were found, which were less than those in adult rats (P<0.01). The cholesterol content was 2.92±0.03 mg/g, 11.20± 3.41 mg/g and 12.91 ± 1.25 mg/g for newly born, the juvenile and the adult groups, respectively, with the differences among them being statistically significant (P<0.01). Our study suggests that the astrocytes may play an important role in the synaptic formation and functional maturity of hippocampal neurons, which may be related to the secretion of cholesterol from astrocytes.

  12. Electrophysiological actions of cyclosporin A and tacrolimus on rat hip-pocampal CA1 pyramidal neurons

    Institute of Scientific and Technical Information of China (English)

    Yong YU; Xue-qin CHEN; Yao-yuan CUI; Guo-yuan HU

    2007-01-01

    Aim: The aim of the present study was to investigate the electrophysiological actions of cyclosporin A (CsA) and tacrolimus (FK506) on neurons in the brain, and to elucidate the relevant mechanisms. Methods: Whole-cell current-clamp recording was made in CA1 pyramidal neurons in rat hippocampal slices; whole- cell voltage-clamp recording was made in dissociated hippocampal CA1 pyrami- dal neurons of rats. Results: CsA (100 μmol/L) and FKS06 (50 μmol/L) did not significantly alter the passive electrical properties of hippocampal CA1 pyramidal neurons, but slowed down the repolarizing phase of the action potential. CsA (10-100 μmol/L) selectively inhibited the delayed rectifier K~ current (IK,) in a concentration-dependent manner. CsA did not affect the kinetic properties of IK. Intracellular dialysis of CsA (100 μmol/L) had no effect on IK. The inhibition of IK by CsA (100/μmol/L) persisted under the low Ca2+ conditions that blocked the basal activity of calcineurin. Conclusion: CsA exerted calcineurin-independent inhibition on the IK in rat hippocampal pyramidal neurons. Taken together with our previous finding with FK506, it is conceivable that the spike broadening caused by the immunosuppressant drugs is due to direct inhibition on the IK.

  13. Synaptic plasticity in the hippocampal area CA1-subiculum projection: implications for theories of memory.

    Science.gov (United States)

    O'Mara, S M; Commins, S; Anderson, M

    2000-01-01

    This paper reviews investigations of synaptic plasticity in the major, and underexplored, pathway from hippocampal area CA1 to the subiculum. This brain area is the major synaptic relay for the majority of hippocampal area CA1 neurons, making the subiculum the last relay of the hippocampal formation prior to the cortex. The subiculum thus has a very major role in mediating hippocampal-cortical interactions. We demonstrate that the projection from hippocampal area CA1 to the subiculum sustains plasticity on a number of levels. We show that this pathway is capable of undergoing both long-term potentiation (LTP) and paired-pulse facilitation (PPF, a short-term plastic effect). Although we failed to induce long-term depression (LTD) of this pathway with low-frequency stimulation (LFS) and two-pulse stimulation (TPS), both protocols can induce a "late-developing" potentiation of synaptic transmission. We further demonstrate that baseline synaptic transmission can be dissociated from paired-pulse stimulation of the same pathway; we also show that it is possible, using appropriate protocols, to change PPF to paired-pulse depression, thus revealing subtle and previously undescribed mechanisms which regulate short-term synaptic plasticity. Finally, we successfully recorded from individual subicular units in the freely-moving animal, and provide a description of the characteristics of such neurons in a pellet-chasing task. We discuss the implications of these findings in relation to theories of the biological consolidation of memory.

  14. Temporal dynamics of distinct CA1 cell populations during unconscious state induced by ketamine.

    Directory of Open Access Journals (Sweden)

    Hui Kuang

    Full Text Available Ketamine is a widely used dissociative anesthetic which can induce some psychotic-like symptoms and memory deficits in some patients during the post-operative period. To understand its effects on neural population dynamics in the brain, we employed large-scale in vivo ensemble recording techniques to monitor the activity patterns of simultaneously recorded hippocampal CA1 pyramidal cells and various interneurons during several conscious and unconscious states such as awake rest, running, slow wave sleep, and ketamine-induced anesthesia. Our analyses reveal that ketamine induces distinct oscillatory dynamics not only in pyramidal cells but also in at least seven different types of CA1 interneurons including putative basket cells, chandelier cells, bistratified cells, and O-LM cells. These emergent unique oscillatory dynamics may very well reflect the intrinsic temporal relationships within the CA1 circuit. It is conceivable that systematic characterization of network dynamics may eventually lead to better understanding of how ketamine induces unconsciousness and consequently alters the conscious mind.

  15. GABAergic interneurons targeting dendrites of pyramidal cells in the CA1 area of the hippocampus.

    Science.gov (United States)

    Klausberger, Thomas

    2009-09-01

    The dendrites of pyramidal cells are active compartments capable of independent computations, input/output transformation and synaptic plasticity. Pyramidal cells in the CA1 area of the hippocampus receive 92% of their GABAergic input onto dendrites. How does this GABAergic input participate in dendritic computations of pyramidal cells? One key to understanding their contribution to dendritic computation lies in the timing of GABAergic input in relation to excitatory transmission, back-propagating action potentials, Ca(2+) spikes and subthreshold membrane dynamics. The issue is further complicated by the fact that dendritic GABAergic inputs originate from numerous distinct sources operating with different molecular machineries and innervating different subcellular domains of pyramidal cell dendrites. The GABAergic input from distinct sources is likely to contribute differentially to dendritic computations. In this review, I describe four groups of GABAergic interneuron according to their expression of parvalbumin, cholecystokinin, axonal arborization density and long-range projections. These four interneuron groups contain at least 12 distinct cell types, which innervate mainly or exclusively the dendrites of CA1 pyramidal cells. Furthermore, I summarize the different spike timing of distinct interneuron types during gamma, theta and ripple oscillations in vivo, and I discuss some of the open questions on how GABAergic input modulates dendritic operations in CA1 pyramidal cells.

  16. Breast cancer 1 (BrCa1 may be behind decreased lipogenesis in adipose tissue from obese subjects.

    Directory of Open Access Journals (Sweden)

    Francisco J Ortega

    Full Text Available CONTEXT: Expression and activity of the main lipogenic enzymes is paradoxically decreased in obesity, but the mechanisms behind these findings are poorly known. Breast Cancer 1 (BrCa1 interacts with acetyl-CoA carboxylase (ACC reducing the rate of fatty acid biosynthesis. In this study, we aimed to evaluate BrCa1 in human adipose tissue according to obesity and insulin resistance, and in vitro cultured adipocytes. RESEARCH DESIGN AND METHODS: BrCa1 gene expression, total and phosphorylated (P- BrCa1, and ACC were analyzed in adipose tissue samples obtained from a total sample of 133 subjects. BrCa1 expression was also evaluated during in vitro differentiation of human adipocytes and 3T3-L1 cells. RESULTS: BrCa1 gene expression was significantly up-regulated in both omental (OM; 1.36-fold, p = 0.002 and subcutaneous (SC; 1.49-fold, p = 0.001 adipose tissue from obese subjects. In parallel with increased BrCa1 mRNA, P-ACC was also up-regulated in SC (p = 0.007 as well as in OM (p = 0.010 fat from obese subjects. Consistent with its role limiting fatty acid biosynthesis, both BrCa1 mRNA (3.5-fold, p<0.0001 and protein (1.2-fold, p = 0.001 were increased in pre-adipocytes, and decreased during in vitro adipogenesis, while P-ACC decreased during differentiation of human adipocytes (p = 0.005 allowing lipid biosynthesis. Interestingly, BrCa1 gene expression in mature adipocytes was restored by inflammatory stimuli (macrophage conditioned medium, whereas lipogenic genes significantly decreased. CONCLUSIONS: The specular findings of BrCa1 and lipogenic enzymes in adipose tissue and adipocytes reported here suggest that BrCa1 might help to control fatty acid biosynthesis in adipocytes and adipose tissue from obese subjects.

  17. Detonator assembly for oil well perforating gun

    Energy Technology Data Exchange (ETDEWEB)

    Regalbuto, J.A.

    1981-02-18

    A safe/arm detonator assembly for use with an oil well perforating gun assembly has 2 housing members isolated from well-bore fluid which are rotatable from a safe position wherein a detonator and a booster are held out of alignment, to an armed position wherein the detonator and booster are moved into alignment. The detonator assembly is further arranged to be installed in a well perforating gun assembly such that the gun assembly may be transported with the detonator assembly in the safe position, and rotated to the armed position at the well site without disassembling the gun assembly. A safety pin may protrude from one of the housing members across a cavity between the members to cover and protect the booster from accidental detonation when the detonator assembly is in the safe position. The detonator and booster cavities may be held aligned by a detent ball. 16 claims.

  18. Thyroid Storm Precipitated by Duodenal Ulcer Perforation

    Directory of Open Access Journals (Sweden)

    Shoko Natsuda

    2015-01-01

    Full Text Available Thyroid storm is a rare and life-threatening complication of thyrotoxicosis that requires prompt treatment. Thyroid storm is also known to be associated with precipitating events. The simultaneous treatment of thyroid storm and its precipitant, when they are recognized, in a patient is recommended; otherwise such disorders, including thyroid storm, can exacerbate each other. Here we report the case of a thyroid storm patient (a 55-year-old Japanese male complicated with a perforated duodenal ulcer. The patient was successfully treated with intensive treatment for thyroid storm and a prompt operation. Although it is believed that peptic ulcer rarely coexists with hyperthyroidism, among patients with thyroid storm, perforation of a peptic ulcer has been reported as one of the causes of fatal outcome. We determined that surgical intervention was required in this patient, reported despite ongoing severe thyrotoxicosis, and reported herein a successful outcome.

  19. Rapunzel syndrome resulting in gastric perforation.

    Science.gov (United States)

    Parakh, J S; McAvoy, A; Corless, D J

    2016-01-01

    We report the case of an 18-year-old female patient with no past medical history who presented to the emergency department with acute abdominal pain and vomiting on the background of a long history of ingesting hair (trichophagia). Computed tomography revealed pneumoperitoneum and free fluid in keeping with visceral perforation. In addition, a large hair bolus was seen extending in contiguity from the stomach to the jejunum. A laparotomy was performed, revealing an anterior gastric perforation secondary to a 120cm long trichobezoar, which had formed a cast of the entire stomach, duodenum and proximal jejunum. The bezoar was removed and an omental patch repair to the anterior ulcer was performed. The patient made an excellent postoperative recovery and was discharged home with psychiatric follow-up review.

  20. Diffuse epithelial ingrowth after perforating keratoplasty.

    Science.gov (United States)

    Severin, M; Kirchhof, B; Hartmann, C

    1987-01-01

    Diffuse epithelial ingrowth was observed in 2 patients after perforating keratoplasty. Both cases involved a corneal graft after perforating injury with aphakia. In the first patient, the epithelial invasion was probably stimulated by a spatula synecholysis. In this case, the diagnosis was only made by histological investigation after enucleation. In the second patient the epithelial ingrowth was observed 8 months after keratoplasty. The clinical diagnosis was made on the basis of the typical slitlamp findings. In this case, the epithelial invasion led to hypotension with high resistance of outflow measured by electrotonography. In a very close chronological relation to the probable fall of chamber fluid secretion, development of a band-shaped keratopathy was observed.

  1. PERFORATED PEPTIC ULCER: A CLINICAL ANALYSIS AND OUTCOME

    Directory of Open Access Journals (Sweden)

    Bijit

    2016-03-01

    Full Text Available BACKGROUND The incidence of perforated peptic ulcer is approximately 7-10 cases per one lakh population per year. Perforation is seen in about 7% of patients hospitalized for peptic ulcer disease. Peptic ulcer perforation, which can be gastric/duodenal perforation can be a serious life-threatening condition if not detected early and treated urgently. Peptic ulcer disease has decreased considerably worldwide with the advent of potent anti-ulcer medicines, but its complication like peptic ulcer perforation has not. Our study is to analyse the clinical, radiological and management related findings in influencing the outcome of patients of peptic ulcer perforation after surgery. MATERIALS AND METHODS A series of 47 patients of peptic ulcer perforation were evaluated. Patients expiring within six hours of admission were not included in this study. RESULTS Age of the patients ranged from 17-80 years. The incidence of perforation was highest in the age group of 41-50 years (31.9%. Out of 47 patients, 41 (87.2% survived. CONCLUSION The incidence of perforation was highest in the age group of 41-50 years. Prognosis becomes poor with age, delayed treatment, shock at admission and concomitant diseases. Direct repair of the perforation with pedicled omentum gave excellent results.

  2. High Temperature Perforating System for Geothermal Applications

    Energy Technology Data Exchange (ETDEWEB)

    Smart, Moises E. [Schlumberger Technology Corporation, Sugar Land, TX (United States)

    2017-02-28

    The objective of this project is to develop a perforating system consisting of all the explosive components and hardware, capable of reliable performance in high temperatures geothermal wells (>200 ºC). In this light we will focused on engineering development of these components, characterization of the explosive raw powder and developing the internal infrastructure to increase the production of the explosive from laboratory scale to industrial scale.

  3. Duodenal Perforation Precipitated by Scrub Typhus

    OpenAIRE

    Raghunath Rajat; David Deepu; Arul Jeevan Jonathan; Abhilash Kundavaram Paul Prabhakar

    2015-01-01

    Scrub typhus is an acute febrile illness usually presenting with fever, myalgia, headache, and a pathognomonic eschar. Severe infection may lead to multiple organ failure and death. Gastrointestinal tract involvement in the form of gastric mucosal erosions and ulcerations owing to vasculitis resulting in gastrointestinal bleeding is common. This process may worsen a pre-existent asymptomatic peptic ulcer, causing duodenal perforation, and present as an acute abdomen requiring surgical explora...

  4. Septum nasal perforation: treatments and literature' review

    OpenAIRE

    Martinez Neto, Eulógio Emílio; Dolci, Luiz Eduardo Lutaif; Murta, Alexandre Antonio; Zanini, Fábio Duro

    2010-01-01

    Introduction: The present study consists in a bibliographical' review concerning the articles related to the different manifestations and forms of the septum nasal perforation, with a main emphasis in the description of its techniques of surgical correction. As the etiology, that is fundamentally iatrogenic, accordingly surgical trauma. Other causes include exhibition to chemical industrial reagents, cocaine use, intranasal steroidal therapeutic, neoplasia and, infectious conditions. There is...

  5. Intrathoracic Gastric Perforation in a Child

    Directory of Open Access Journals (Sweden)

    Mithat Günaydın

    2012-04-01

    Full Text Available Introduction: Paraesophageal hernia (PEH is a rare condition in children. The symptomatology of these patients is usually non-specific in the form of repeated attacks of respiratory infection and/or recurrent attacks of vomiting but can also lead to serious complications such as intrathoracic gastric strangulation and perforation. Case Report: A 6-year old girl was referred from a regional hospital for haematemesis and abdominal pain. She had fever and sepsis. Physical examination revealed abdominal tenderness, rebound and failure to thrive. Air-fluid level was seen in the posterior of left hemithorax at the AP and lateral chest radiographs. Thorax CT demonstrated pleural fluid, opacity, volume loss and left lung being pushed to the right of heart. Stomach and splenic flexura were moved to the left hemithorax. At laparatomy, stomach and splenic flexura had passed along the esophageal hiatus toward the chest and fundus of the stomach was perforated within the hernia sac. Greater curvature and fundus of the stomach were necrotic and hernia sac and intraabdominal space was filled with food. Stomach was pulled into the abdomen. Hernia sac was excised and defect was primarly repaired. Necrotic areas of the stomach were debrided. Then, perforation of stomach was repaired and gastrostomy was performed. Control esophagogastroduodenography revealed a 2 cm filling defect at the greater curvature and fundus of stomach due to previous gastric resection. Antireflux medical treatment was successful.Conclusion: PEH may be asymptomatic and encountered incidentally. It has the potential for serious complications such as strangulation and perforation which may present with unusual symptoms and physical findings reflecting the original pathology. Due to the risk of these serious complications, elective surgical repair is necessary after diagnosis. (Jo­ur­nal of Cur­rent Pe­di­at­rics 2012; 10: 36-9

  6. Liquid nitrogen ingestion followed by gastric perforation.

    Science.gov (United States)

    Berrizbeitia, Luis D; Calello, Diane P; Dhir, Nisha; O'Reilly, Colin; Marcus, Steven

    2010-01-01

    Ingestion of liquid nitrogen is rare but carries catastrophic complications related to barotrauma to the gastrointestinal tract. We describe a case of ingestion of liquid nitrogen followed by gastric perforation and respiratory insufficiency and discuss the mechanism of injury and management of this condition. Liquid nitrogen is widely available and is frequently used in classroom settings, in gastronomy, and for recreational purposes. Given the potentially lethal complications of ingestion, regulation of its use, acquisition, and storage may be appropriate.

  7. Surgical complications of typhoid fever: enteric perforation.

    Science.gov (United States)

    Santillana, M

    1991-01-01

    Typhoid fever remains a prevalent disease in developing nations as the result of adverse socioeconomic factors. The most frequent complication, and principal cause of mortality, is perforation of the terminal ileum. This report presents our experience with 96 patients surgically treated at Cayetano Heredia University Hospital in Lima, Peru from 1972 to 1986. The clinical characteristics and the diverse surgical procedures utilized in the management of these patients are reviewed.

  8. Vitrectomy in double-perforation gunshot injury

    Directory of Open Access Journals (Sweden)

    Abd El Alim Mohamed A

    2013-11-01

    Full Text Available Ahmed Abd El Alim MohamedOphthalmology department, Ain Shams University, Cairo, EgyptObjective: This study sought to evaluate the result of pars plana vitrectomy in patients with gunshot wounds involving double perforation.Methods: This was a retrospective, noncomparative, interventional case series.Results: Eighteen patients (18 eyes with double-perforation gunshot injuries were treated from February 2010 to March 2012. The group included 16 men (88% and two women (11%; the mean age was 24 (15–33 years. In each case, vitrectomy was scheduled 1–6 weeks after repair of the entrance site. Associated retinal detachments were observed in two eyes (11%, retinal incarceration was observed surrounding the exit site in three eyes (16%, and retention of an intraocular foreign body was observed in two cases. After a follow-up period of 8 ± 2 months, two eyes (11% had achieved visual acuity (VA of 0.5, nine eyes (50% had achieved VA between 0.5 and 0.1, and seven eyes (38% had achieved VA between 0.1 and hand movement. The main reasons for functional failure (VA 0.1 to hand movement were macular dragging (due to fibrosis at the exit site near the macula in seven cases (38%, submacular hemorrhage in four cases (22%, and epimacular fibrosis in five cases (27%. All cases developed postoperative exotropia. One case (5% developed postoperative hemorrhage. No cases exhibited signs of postoperative redetachment.Conclusion: The outcome of pars plana vitrectomy in cases with double perforations is variable. Factors including the surgeon's skill level, the time to surgery, and the efficacy of the intraocular tamponade affect the postoperative outcome.Keywords: pars plana vitrectomy, gunshot injury, double perforation

  9. Gastric schwannoma coexists with peptic ulcer perforation

    Directory of Open Access Journals (Sweden)

    Volkan İnce

    2011-09-01

    Full Text Available Gastric schwannoma is a benign neoplasm that originates from sheet of nerve cell in stomach. Differential diagnosis of gastrointestinal stromal tumors, (GISTs which have malign potential, than these tumors, which definite diagnosis is determined by histopathological and immunohistochemical methods have clinical significance due to gastric schwannomas have excellent progress after surgical resection. We presented a case of gastric schwannoma coexists with peptic ulcer perforation with guide of literature in this study.

  10. Urosepsis complicated by a spontaneous bladder perforation.

    Science.gov (United States)

    Lutwak, Nancy; Dill, Curt

    2011-11-08

    The authors present a case of a 72-year-old diabetic male s/p pelvic irradiation for prostate carcinoma who arrived in the emergency department with complaints of shaking chills. After admission for urosepsis, he developed severe abdominal pain and examination revealed a diffusely tender abdomen. The patient was diagnosed with spontaneous urinary bladder perforation and underwent surgery. After several weeks of intravenous antibiotics, he was discharged with multiple drains in place and bilateral nephrostomy tubes.

  11. Traumatic Tympanic Membrane perforation: An aetiological profile

    Directory of Open Access Journals (Sweden)

    Alabi Biodun S

    2009-11-01

    Full Text Available Abstract Background Traumatic perforation of the tympanic membrane may be due to direct or indirect source. The aim of the study is to profile the various aetiologies of traumatic tympanic membrane perforation in Ilorin, north central Nigeria. A retrospective review of 64 patients seen at the University of Ilorin Teaching hospital, Ilorin, Nigeria over a ten year period (January 1998 to Dec 2007 with history of traumatic tympanic membrane perforation from various causes, these also included multiply injured patients with bleeding from middle ear as part of their presentations. The data retrieved included the biodata, the clinical presentations, source of injury, the clinical findings and the treatment outcome. The data were entered into an SPSS version 11 computer soft ware and analyzed descriptively. Findings Sixty four (64 ears were analysed, Age range 6 months to 50 yrs, mean age of 29.2 yrs 7.9% of them were ≤5 years, 29.7% between 21-34 years, and 37.7% were 35 years and above. The male to female ratio was 2.5:1.0. Commonest aetiology was from slaps, then road traffic injury (RTI in 35.9% and 23.5%, Majority of the slap injury were from fights (30.5%, security agents, senior students and cultists at schools (17.4% each. Sudden hearing loss was a typical presentation (95.3%, majority of the patient defaulted from follow up once the symptoms of bleeding and pain subsided. Only 7.8% had neomembrane formation on follow up Conclusion Traumatic perforation of the tympanic membrane is an uncommon injury that is under-reported, there is the need to educate on alternative punitive measure among students and security agents, unskilled removal of foreign body, early identification, evaluation and referral of patients reduces the attendant morbidity.

  12. Typhoid ileal perforation: a 13-year experience

    Directory of Open Access Journals (Sweden)

    Poras Chaudhary

    2015-07-01

    Full Text Available Typhoid fever is endemic in many developing countries with a high rate of complications. Aim of this study is to analyse epidemiological features, clinical presentations, complications and therapeutic outcomes of enteric perforation peritonitis diagnosed and treated in our hospital. Records of total number of 646 patients, who presented with perforation peritonitis due to enteric fever in the surgical emergency unit of Dr Ram Manohar Lohia hospital, New Delhi between January 2001 and December 2013, were reviewed retrospectively. Descriptive statistics was used to analyze the data. Out of 646 patients, 62 (9.59% presented in shock. Stomal, peristomal, local and systemic complications were high in these patients. Primary closure was done in 212 (33.12 patients, primary ileostomy was created in 410 (64.06 patients, and resection and anastomosis was done in 24 (3.75 patients. Thirteen patients (2.01% died of typhoid intestinal perforation. To prevent complications of typhoid fever, in addition to control sanitation, it is also important to control quackery and malpractices. Awareness and education about the disease, its nature and complications will also be of great help.

  13. Perforated jejunal diverticula: a case report

    Directory of Open Access Journals (Sweden)

    Collins Christopher G

    2010-06-01

    Full Text Available Abstract Introduction Jejunal diverticula are rare and are usually asymptomatic. However, they may cause chronic non-specific symptoms or rarely lead to an acute presentation. Case presentation We report the case of an 82-year-old Caucasian woman presenting with a one-day history of generalized abdominal pain, with three episodes of vomiting. An abdominal X-ray displayed multiple dilated loops of the small bowel. A subsequent computed tomography scan of the abdomen and pelvis revealed a thickening of the duodenum and dilatation of the proximal jejunum. Multiple small bowel diverticula were identified with surrounding pockets of free air adjacent to the jejunal diverticula suggestive of a small bowel perforation. Our patient underwent a laparotomy, which identified multiple jejunal diverticula with two pinhole jejunal perforations and associated fecal contamination. The perforations were repaired with primary closure and extensive washout was performed. Conclusion Jejunal diverticulosis in the elderly can lead to significant morbidity and mortality and so should be suspected in those presenting with crampy abdominal pain and altered bowel habits.

  14. [Perforated duodenal diverticulum: report of a case].

    Science.gov (United States)

    Gulotta, G; Agosta, G; Romano, G

    2001-01-01

    After the colon, the duodenum is the most common site of diverticula. Duodenal diverticula can be divided into two types: intraluminal or extraluminal. The latter are more frequent, with a prevalence ranging from 0.6 to 27% in relation to the diagnostic methods utilized. Females are more often affected than males. About 70-75% of extraluminal duodenal diverticula are located in a circular area centred around the ampulla of Vater within a radius of 2-3 cm; these are defined as periampullary or juxtapapillary. Perforation is the rarest type of complication and can simulate different clinical conditions. CT plays a fundamental role in diagnosis also in relation to the different diverticular topography. Perforation is an indication for emergency surgery. The authors describe the clinical case of a duodenal diverticulum containing the outlet of the papilla, complicated by perforation; CT showed retroduodenal fluid and free air. Emergency surgery with an external biliary drainage, naso-biliary probe, and a diverticulo-jejunostomy on a Roux-en-Y defunctionalised loop, resolved the condition.

  15. Tuberculous gastric perforation: report of a case.

    Science.gov (United States)

    Sharma, Deborshi; Gupta, Arun; Jain, Bhupendra Kumar; Agrawal, Vivek; Dargan, Puneet; Upreti, Lalendra; Arora, Vinod

    2004-01-01

    A 21-year-old woman presented with a 2-day history of acute abdominal pain. Contrast-enhanced computed tomography (CT) showed a perforation in the lesser curve of the stomach. The patient suffered a bout of hematemesis, following which an endoscopy showed a bleeding blood vessel at the edge of the perforation. We performed an emergency distal gastrectomy, including the ulcer site. Histopathological examination revealed tuberculous granulation tissue and acid-fast bacilli in the ulcer. The patient was given antituberculosis therapy (ATT) postoperatively, and was well when last seen 1 year 5 months after surgery. We analyzed the clinical data of five cases of tuberculous gastric perforation (TGP), reported between 1948 and 2003, including our patient. The patients ranged in age from 21 to 45 years, with a mean age of 36.8 years (SD +/- 10.21), and a male to female ratio of 3 : 2. The diagnosis was confirmed by surgery or autopsy. Abdominal lymphadenopathy was present in all patients. Gastrectomy was performed in four patients, and two were given ATT. All four patients in the previous reports died of their disease.

  16. Kinetic changes and modulation by carbamazepine on voltage-gated sodium channels in rat CA1 neurons after epilepsy.

    NARCIS (Netherlands)

    G. Sun; T.R. Werkman; W.J. Wadman

    2006-01-01

    AIM: To study whether the functional properties of sodium channels, and subsequently the channel modulation by carbamazepine (CBZ) in hippocampal CA1 neurons can be changed after epileptic seizures. METHODS: We used the acutely dissociated hippocampal CA1 pyramidal cells from epilepsy model rats 3 w

  17. Ischemic damage in hippocampal CA1 is dependent on glutamate release and intact innervation from CA3

    DEFF Research Database (Denmark)

    Benveniste, H; Jørgensen, M B; Sandberg, M;

    1989-01-01

    The removal of glutamatergic afferents to CA1 by destruction of the CA3 region is known to protect CA1 pyramidal cells against 10 min of transient global ischemia. To investigate further the pathogenetic significance of glutamate, we measured the release of glutamate in intact and CA3-lesioned CA...... is dependent on glutamate release and intact innervation from CA3....

  18. Cell-type-specific circuit connectivity of hippocampal CA1 revealed through Cre-dependent rabies tracing.

    Science.gov (United States)

    Sun, Yanjun; Nguyen, Amanda Q; Nguyen, Joseph P; Le, Luc; Saur, Dieter; Choi, Jiwon; Callaway, Edward M; Xu, Xiangmin

    2014-04-10

    We developed and applied a Cre-dependent, genetically modified rabies-based tracing system to map direct synaptic connections to specific CA1 neuron types in the mouse hippocampus. We found common inputs to excitatory and inhibitory CA1 neurons from CA3, CA2, the entorhinal cortex (EC), the medial septum (MS), and, unexpectedly, the subiculum. Excitatory CA1 neurons receive inputs from both cholinergic and GABAergic MS neurons, whereas inhibitory neurons receive a great majority of inputs from GABAergic MS neurons. Both cell types also receive weaker input from glutamatergic MS neurons. Comparisons of inputs to CA1 PV+ interneurons versus SOM+ interneurons showed similar strengths of input from the subiculum, but PV+ interneurons received much stronger input than SOM+ neurons from CA3, the EC, and the MS. Thus, rabies tracing identifies hippocampal circuit connections and maps how the different input sources to CA1 are distributed with different strengths on each of its constituent cell types.

  19. Catheter perforation of distal oesophagus with duodenal re-entry of catheter. Report of a case

    Energy Technology Data Exchange (ETDEWEB)

    Bundgaard, T.; Kristensen, H.; Lesak, F.

    An unusual case of perforation of the oesophagus is presented. A nasogastric tube had perforated the oesophagus and re-penetrated into the duodenum, and thereby re-entered the gastrointestinal tract without perforating the peritoneum and without causing the classical clinical signs of oesophageal perforation. Treatment was started 31 days after the perforation.

  20. Low-Cost Control Problems on Perforated and Non-Perforated Domains

    Indian Academy of Sciences (India)

    S Kesavan; T Muthukumar

    2008-02-01

    We study the homogenization of a class of optimal control problems whose state equations are given by second order elliptic boundary value problems with oscillating coefficients posed on perforated and non-perforated domains. We attempt to describe the limit problem when the cost of the control is also of the same order as that describing the oscillations of the coefficients. We study the situations where the control and the state are both defined over the entire domain or when both are defined on the boundary.

  1. Perforation of the duodenum by an ingested toothbrush

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We report a rare case of duodenal perforation caused by an ingested 12-cm long toothbrush handle. A 22-year-old female presented with intermittent epigas- tric pain for 6 d after swallowing a broken toothbrush. The swallowed toothbrush could not be removed from the second portion of the duodenum by endoscopy. Laparotomy revealed a perforation in the anterior wall of the duodenal bulb. The toothbrush was removed via the perforation which was debrided and closed. There were no postoperative complications.

  2. Perforation of the duodenum by an ingested toothbrush

    OpenAIRE

    Chao, Hsiao-Hsiang; Chao, Tzu-Chieh

    2008-01-01

    We report a rare case of duodenal perforation caused by an ingested 12-cm long toothbrush handle. A 22-year-old female presented with intermittent epigastric pain for 6 d after swallowing a broken toothbrush. The swallowed toothbrush could not be removed from the second portion of the duodenum by endoscopy. Laparotomy revealed a perforation in the anterior wall of the duodenal bulb. The toothbrush was removed via the perforation which was debrided and closed. There were no postoperative compl...

  3. Typhoid perforation of small bowel: a study of 72 cases.

    Science.gov (United States)

    Noorani, M A; Sial, I; Mal, V

    1997-08-01

    Typhoid perforation, a serious complication of typhoid fever, is still common in Third World countries and has a mortality rate between 1 and 39.3% according to various reports. There are different approaches to the treatment of typhoid perforation. Early surgical intervention with simple closure of the perforation in two layers has good results and negligible mortality. It is easy to perform and can be carried out, even by a trainee surgeon.

  4. Perforated duodenal diverticulum caused by Bezoar: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Jung; Moon, Sung Kyoung; Park, Seong Jin; Lim, Joo Won; Lee, Dong Ho; Ko, Young Tae [Dept. of Radiology, College of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

    2013-11-15

    Duodenal diverticulum is common, but its perforation is a rare complication. Duodenal diverticulum perforation requires prompt treatments because of its high mortality rate. However, an accurate diagnosis is difficult to make due to nonspecific symptoms and signs. It can be misdiagnosed as pancreatitis, cholecystitis, or peptic ulcer. Herein, we report a case of perforated duodenal diverticulum caused by bezoar in a 33-year-old woman whom was diagnosed by abdomen computed tomography and ultrasonography.

  5. Low Voltage Electric Current Causing Ileal Perforation: A Rare Injury

    Science.gov (United States)

    Mathur, Vinay; Tanger, Ramesh; Gupta, Arun Kumar

    2016-01-01

    Post-electric burn ileal perforation is a rare but severe complication leading to high morbidity and mortality if there is delay in diagnosis and management. We are describing a case of electric current injury of left forearm, chest, and abdominal wall with perforation of ileum in an 8-year old boy. Patient was successfully managed by primary closure of the ileal perforation. PMID:27170922

  6. Low Voltage Electric Current Causing Ileal Perforation: A Rare Injury

    Directory of Open Access Journals (Sweden)

    Aditya Pratap Singh

    2016-04-01

    Full Text Available Post-electric burn ileal perforation is a rare but severe complication leading to high morbidity and mortality if there is delay in diagnosis and management. We are describing a case of electric current injury of left forearm, chest, and abdominal wall with perforation of ileum in an 8-year old boy. Patient was successfully managed by primary closure of the ileal perforation.

  7. Aortic Pseudoaneurysm Secondary to Mediastinitis due to Esophageal Perforation

    Directory of Open Access Journals (Sweden)

    Claudia Patricia Zuluaga

    2016-01-01

    Full Text Available Esophageal perforation is a condition associated with high morbidity and mortality rates; it requires early diagnosis and treatment. The most common complication of esophageal rupture is mediastinitis. There are several case reports in the literature of mediastinitis secondary to esophageal perforation and development of aortic pseudoaneurysm as a complication. We report the case of a patient with an 8-day history of esophageal perforation due to foreign body (fishbone with mediastinitis and aortic pseudoaneurysm. The diagnosis was made using Computed Tomography (CT with intravenous and oral water-soluble contrast material. An esophagogastroduodenoscopy did not detect the perforation.

  8. An Unusual Etiology of Spontaneous Pyometra Perforation; A Case Report

    Science.gov (United States)

    Agarwal, Rachna; Suneja, Amita; Sharma, Abha; Vaid, Neelam Bala

    2011-01-01

    Introduction By presenting this case we aimed to describe an uncommon complication of generalized peritonitis following spontaneous pyometra perforation in untreated cervical carcinoma. Case Presentation This report describes a 60-year-old postmenopausal woman presenting with clinical features mimicking intestinal perforation who was later diagnosed as cervical carcinoma with pyometra perforation at exploratory laparotomy. The patient had good post-operative recovery following drainage and peritoneal lavage. Conclusion Spontaneous pyometra perforation in a case of untreated carcinoma of cervix is a rare condition, yet it should be suspected and kept in the differential diagnosis of acute abdomen in elderly women. PMID:23926508

  9. Spontaneous common bile duct perforation due to periampullary growth

    Directory of Open Access Journals (Sweden)

    Pandiaraja Javabal

    2014-06-01

    Full Text Available Spontaneous common bile duct perforations are an unusual cause of acute abdomen. In spontaneous common bile duct perforation, malignant growth is even rare. It is a rare entity usually reported in infants and children due to congenital anomalies. It is rarely reported in adults. In this case report, a 55 - year - old male patient who was diagnosed as a duodenal perforation in the pre - operative period, but the intra - operative findings was common bile duct perforation due to periampullary growth, is reported

  10. PERFORATION OF PLASTIC SPHERICAL SHELLS UNDER IMPACT BY CYLINDRICAL PROJECTILES

    Institute of Scientific and Technical Information of China (English)

    NING Jian-guo; SONG Wei-dong

    2006-01-01

    The objective is to study the perforation of a plastic spherical shell impacted by a cylindrical projectile. First, the deformation modes of the shell were given by introducing an isometric transformation. Then, the perforation mechanism of the shell was analyzed and an analytical model was advanced. Based on Hamilton principle, the governing equation was obtained and solved using Runge-Kuta method. Finally, some important theoretical predictions were given to describe the perforation mechanism of the shell. The results will play an important role in understanding the perforation mechanism of spherical shells impacted by a projectile.

  11. Imaging gastrointestinal perforation in pediatric blunt abdominal trauma

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, D.H. [Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8 (Canada); Babyn, P.S. [Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8 (Canada); Pearl, R. [Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8 (Canada)

    1996-03-01

    Objective. To assess the role of imaging, in particular CT, in the early detection of GI perforation. Subjects and methods. In a 10-year period, 43 patients with surgically confirmed GI perforation were identified from hospital records; 22 of these had preoperative CT evaluation. Medical records and radiology were retrospectively reviewed and CT studies were particularly assessed for extraluminal air, free intraperitoneal fluid, bowel wall thickening, bowel wall enhancement, and bowel dilatation. During the study period an additional 12 trauma patients were identified who had CT studies demonstrating the above findings, but who had hypovolemic shock bowel or nondisrupting bowel injury without perforation evident. Results. Extraluminal air was demonstrated in 47 % of the imaged perforations. There was one false-positive extraluminal air. Perforation was confirmed in patients who had all five of the above CT findings, but this was the case for only 18 % of patients with perforation. One or more of the five specified CT findings were present in all CT studies reviewed. No false-negative CT study was performed in the study period. Conclusion. Separating nondisrupting bowel injury from perforation is diagnostically difficult; however, CT remains a good modality for assessing GI perforation in pediatric blunt trauma, but it cannot replace diligent and repeated clinical evaluation of all potential perforation victims. (orig.). With 4 figs., 1 tab.

  12. Persistent sodium current drives conditional pacemaking in CA1 pyramidal neurons under muscarinic stimulation.

    Science.gov (United States)

    Yamada-Hanff, Jason; Bean, Bruce P

    2013-09-18

    Hippocampal CA1 pyramidal neurons are normally quiescent but can fire spontaneously when stimulated by muscarinic agonists. In brain slice recordings from mouse CA1 pyramidal neurons, we examined the ionic basis of this activity using interleaved current-clamp and voltage-clamp experiments. Both in control and after muscarinic stimulation, the steady-state current-voltage curve was dominated by inward TTX-sensitive persistent sodium current (I(NaP)) that activated near -75 mV and increased steeply with depolarization. In control, total membrane current was net outward (hyperpolarizing) near -70 mV so that cells had a stable resting potential. Muscarinic stimulation activated a small nonselective cation current so that total membrane current near -70 mV shifted to become barely net inward (depolarizing). The small depolarization triggers regenerative activation of I(NaP), which then depolarizes the cell from -70 mV to spike threshold. We quantified the relative contributions of I(NaP), hyperpolarization-activated cation current (I(h)), and calcium current to pacemaking by using the cell's own firing as a voltage command along with specific blockers. TTX-sensitive sodium current was substantial throughout the entire interspike interval, increasing as the membrane potential approached threshold, while both Ih and calcium current were minimal. Thus, spontaneous activity is driven primarily by activation of I(NaP) in a positive feedback loop starting near -70 mV and providing increasing inward current to threshold. These results show that the pacemaking "engine" from I(NaP) is an inherent property of CA1 pyramidal neurons that can be engaged or disengaged by small shifts in net membrane current near -70 mV, as by muscarinic stimulation.

  13. Changes in membrane properties of CA1 pyramidal neurons after transient forebrain ischemia in vivo.

    Science.gov (United States)

    Gao, T M; Pulsinelli, W A; Xu, Z C

    1999-03-01

    We have previously identified three distinct populations of CA1 pyramidal neurons after reperfusion based on differences in synaptic response, and named these late depolarizing postsynaptic potential neurons (enhanced synaptic transmission), non-late depolarizing postsynaptic potential and small excitatory postsynaptic neurons (depressed synaptic transmission). In the present study, spontaneous activity and membrane properties of CA1 neurons were examined up to 48 h following approximately 14 min ischemic depolarization using intracellular recording and staining techniques in vivo. In comparison with preischemic properties, the spontaneous firing rate and the spontaneous synaptic activity of CA1 neurons decreased significantly during reperfusion; spontaneous synaptic activity ceased completely 36-48 h after reperfusion, except for a low level of activity which persisted in non-late depolarizing postsynaptic potential neurons. Neuronal hyperactivity as indicated by increasing firing rate was never observed in the present study. The membrane input resistance and time constant decreased significantly in late depolarizing postsynaptic potential neurons at 24-48 h reperfusion. In contrast, similar changes were not observed in non-late depolarizing postsynaptic potential neurons. The rheobase, spike threshold and spike frequency adaptation in late depolarizing postsynaptic potential neurons increased progressively following reperfusion. Only a transient increase in rheobase and spike threshold was detected in non-late depolarizing postsynaptic potential neurons and spike frequency adaptation remained unchanged in these neurons. The amplitude of fast afterhyperpolarization increased in all neurons after reperfusion, with the smallest increment in non-late depolarizing postsynaptic potential neurons. Small excitatory postsynaptic potential neurons shared similar changes to those of late depolarizing postsynaptic potential neurons. These results suggest that the enhancement

  14. Memory Dysfunction in Type 2 Diabetes Mellitus Correlates with Reduced Hippocampal CA1 and Subiculum Volumes

    Institute of Scientific and Technical Information of China (English)

    Yan-Wei Zhang; Jiu-Quan Zhang; Chen Liu; Ping Wei; Xiao Zhang; Qiao-Ying Yuan; Xun-Tao Yin

    2015-01-01

    Background:Little attention has been paid to the role of subcortical deep gray matter (SDGM) structures in type 2 diabetes mellitus (T2DM)-induced cognitive impairment,especially hippocampal subfields.Our aims were to assess the in vivo volumes of SDGM structures and hippocampal subfields using magnetic resonance imaging (MRI) and to test their associations with cognitive performance in T2DM.Methods:A total of 80 T2DM patients and 80 neurologically unimpaired healthy controls matched by age,sex and education level was enrolled in this study.We assessed the volumes of the SDGM structures and seven hippocampal subfields on MRI using a novel technique that enabled automated volumetry.We used Mini-Mental State Examination and Montreal Cognitive Assessment (MoCA) scores as measures of cognitive performance.The association of glycosylated hemoglobin (HbAlc) with SDGM structures and neuropsychological tests and correlations between hippocampal subfields and neuropsychological tests were assessed by partial correlation analysis in T2DM.Results:Bilaterally,the hippocampal volumes were smaller in T2DM patients,mainly in the CA1 and subiculum subfields.Partial correlation analysis showed that the MoCA scores,particularly those regarding delayed memory,were significantly positively correlated with reduced hippocampal CA 1 and subiculum volumes in T2DM patients.Additionally,higher HbA1c levels were significantly associated with poor memory performance and hippocampal atrophy among T2DM patients.Conclusions:These data indicate that the hippocampus might be the main affected region among the SDGM structures in T2DM.These structural changes in the hippocampal CA1 and subiculum areas might be at the core of underlying neurobiological mechanisms of hippocampal dysfunction,suggesting that degeneration in these regions could be responsible for memory impairments in T2DM patients.

  15. Memory Dysfunction in Type 2 Diabetes Mellitus Correlates with Reduced Hippocampal CA1 and Subiculum Volumes

    Directory of Open Access Journals (Sweden)

    Yan-Wei Zhang

    2015-01-01

    Full Text Available Background: Little attention has been paid to the role of subcortical deep gray matter (SDGM structures in type 2 diabetes mellitus (T2DM-induced cognitive impairment, especially hippocampal subfields. Our aims were to assess the in vivo volumes of SDGM structures and hippocampal subfields using magnetic resonance imaging (MRI and to test their associations with cognitive performance in T2DM. Methods: A total of 80 T2DM patients and 80 neurologically unimpaired healthy controls matched by age, sex and education level was enrolled in this study. We assessed the volumes of the SDGM structures and seven hippocampal subfields on MRI using a novel technique that enabled automated volumetry. We used Mini-Mental State Examination and Montreal Cognitive Assessment (MoCA scores as measures of cognitive performance. The association of glycosylated hemoglobin (HbA1c with SDGM structures and neuropsychological tests and correlations between hippocampal subfields and neuropsychological tests were assessed by partial correlation analysis in T2DM. Results: Bilaterally, the hippocampal volumes were smaller in T2DM patients, mainly in the CA1 and subiculum subfields. Partial correlation analysis showed that the MoCA scores, particularly those regarding delayed memory, were significantly positively correlated with reduced hippocampal CA1 and subiculum volumes in T2DM patients. Additionally, higher HbA1c levels were significantly associated with poor memory performance and hippocampal atrophy among T2DM patients. Conclusions: These data indicate that the hippocampus might be the main affected region among the SDGM structures in T2DM. These structural changes in the hippocampal CA1 and subiculum areas might be at the core of underlying neurobiological mechanisms of hippocampal dysfunction, suggesting that degeneration in these regions could be responsible for memory impairments in T2DM patients.

  16. Regulation of GABA Equilibrium Potential by mGluRs in Rat Hippocampal CA1 Neurons.

    Science.gov (United States)

    Yang, Bo; Rajput, Padmesh S; Kumar, Ujendra; Sastry, Bhagavatula R

    2015-01-01

    The equilibrium potential for GABA-A receptor mediated currents (EGABA) in neonatal central neurons is set at a relatively depolarized level, which is suggested to be caused by a low expression of K+/Cl- co-transporter (KCC2) but a relatively high expression of Na+-K+-Cl- cotransporter (NKCC1). Theta-burst stimulation (TBS) in stratum radiatum induces a negative shift in EGABA in juvenile hippocampal CA1 pyramidal neurons. In the current study, the effects of TBS on EGABA in neonatal and juvenile hippocampal CA1 neurons and the underlying mechanisms were examined. Metabotropic glutamate receptors (mGluRs) are suggested to modulate KCC2 and NKCC1 levels in cortical neurons. Therefore, the involvement of mGluRs in the regulation of KCC2 or NKCC1 activity, and thus EGABA, following TBS was also investigated. Whole-cell patch recordings were made from Wistar rat hippocampal CA1 pyramidal neurons, in a slice preparation. In neonates, TBS induces a positive shift in EGABA, which was prevented by NKCC1 antisense but not NKCC1 sense mRNA. (RS)-a-Methyl-4-carboxyphenylglycine (MCPG), a group I and II mGluR antagonist, blocked TBS-induced shifts in both juvenile and neonatal hippocampal neurons. While blockade of mGluR1 or mGluR5 alone could interfere with TBS-induced shifts in EGABA in neonates, only a combined blockade could do the same in juveniles. These results indicate that TBS induces a negative shift in EGABA in juvenile hippocampal neurons but a positive shift in neonatal hippocampal neurons via corresponding changes in KCC2 and NKCC1 expressions, respectively. mGluR activation seems to be necessary for both shifts to occur while the specific receptor subtype involved seems to vary.

  17. Regulation of GABA Equilibrium Potential by mGluRs in Rat Hippocampal CA1 Neurons.

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    Bo Yang

    Full Text Available The equilibrium potential for GABA-A receptor mediated currents (EGABA in neonatal central neurons is set at a relatively depolarized level, which is suggested to be caused by a low expression of K+/Cl- co-transporter (KCC2 but a relatively high expression of Na+-K+-Cl- cotransporter (NKCC1. Theta-burst stimulation (TBS in stratum radiatum induces a negative shift in EGABA in juvenile hippocampal CA1 pyramidal neurons. In the current study, the effects of TBS on EGABA in neonatal and juvenile hippocampal CA1 neurons and the underlying mechanisms were examined. Metabotropic glutamate receptors (mGluRs are suggested to modulate KCC2 and NKCC1 levels in cortical neurons. Therefore, the involvement of mGluRs in the regulation of KCC2 or NKCC1 activity, and thus EGABA, following TBS was also investigated. Whole-cell patch recordings were made from Wistar rat hippocampal CA1 pyramidal neurons, in a slice preparation. In neonates, TBS induces a positive shift in EGABA, which was prevented by NKCC1 antisense but not NKCC1 sense mRNA. (RS-a-Methyl-4-carboxyphenylglycine (MCPG, a group I and II mGluR antagonist, blocked TBS-induced shifts in both juvenile and neonatal hippocampal neurons. While blockade of mGluR1 or mGluR5 alone could interfere with TBS-induced shifts in EGABA in neonates, only a combined blockade could do the same in juveniles. These results indicate that TBS induces a negative shift in EGABA in juvenile hippocampal neurons but a positive shift in neonatal hippocampal neurons via corresponding changes in KCC2 and NKCC1 expressions, respectively. mGluR activation seems to be necessary for both shifts to occur while the specific receptor subtype involved seems to vary.

  18. Neuroprotective effect of olive oil in the hippocampus CA1 neurons following ischemia: Reperfusion in mice

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    M Zamani

    2013-01-01

    Full Text Available Introduction: Transient global ischemia induces selective, delayed neuronal death of pyramidal neurons in the hippocampal CA1. Oxidative Stress is considered to be involved in a number of human diseases including ischemia. Preliminary studies confirmed reduction of cell death in brain following treatment with antioxidants. Aim: According to this finding, we study the relationship between consumption of olive oil on cell death and memory disorder in brain ischemia. We studied the protective effect of olive oil against ischemia-reperfusion. Material and Methods: Experimental design includes three groups: Intact (n = 8, ischemic control (n = 8 and treatment groups with olive oil (n = 8. The mice treated with olive oil as pre-treatment for a week. Then, ischemia induced by common carotid artery ligation and following the reduction of inflammation [a week after ischemia], the mice post-treated with olive oil. Nissl staining applied for counting necrotic cells in hippocampus CA1. Tunnel kit was used to quantify apoptotic cell death while to short term memory scale, we apply y-maze and shuttle box tests and for detection the rate of apoptotic and treated cell, we used western blotting test for bax and bcl2 proteins. Results: High rate of apoptosis was seen in ischemic group that significantly associated with short-term memory loss. Cell death was significantly lower when mice treated with olive oil. The memory test results were adjusted with cell death results and bax and bcl2 expression in all groups′ comparison. Ischemia for 15 min induced cell death in hippocampus with more potent effect on CA1. Conclusion: Olive oil intake significantly reduced cell death and decreased memory loss.

  19. M-type potassium channels modulate Schaffer collateral-CA1 glutamatergic synaptic transmission.

    Science.gov (United States)

    Sun, Jianli; Kapur, Jaideep

    2012-08-15

    Previous studies have suggested that muscarinic receptor activation modulates glutamatergic transmission. M-type potassium channels mediate the effects of muscarinic activation in the hippocampus, and it has been proposed that they modulate glutamatergic synaptic transmission. We tested whether M1 muscarinic receptor activation enhances glutamatergic synaptic transmission via the inhibition of the M-type potassium channels that are present in Schaffer collateral axons and terminals. Miniature excitatory postsynaptic currents (mEPSCs) were recorded from CA1 pyramidal neurons. The M1 receptor agonist, NcN-A-343, increased the frequency of mEPSCs, but did not alter their amplitude. The M-channel blocker XE991 and its analogue linopirdine also increased the frequency of mEPSCs. Flupirtine, which opens M-channels, had the opposite effect. XE991 did not enhance mEPSCs frequency in a calcium-free external medium. Blocking P/Q- and N-type calcium channels abolished the effect of XE991 on mEPSCs. These data suggested that the inhibition of M-channels increases presynaptic calcium-dependent glutamate release in CA1 pyramidal neurons. The effects of these agents on the membrane potentials of presynaptic CA3 pyramidal neurons were studied using current clamp recordings; activation of M1 receptors and blocking M-channels depolarized neurons and increased burst firing. The input resistance of CA3 neurons was increased by the application of McN-A-343 and XE991; these effects were consistent with the closure of M-channels. Muscarinic activation inhibits M-channels in CA3 pyramidal neurons and its efferents – Schaffer collateral, which causes the depolarization, activates voltage-gated calcium channels, and ultimately elevates the intracellular calcium concentration to increase the release of glutamate on CA1 pyramidal neurons.

  20. Multi-walled carbon nanotube inhibits CA1 glutamatergic synaptic transmission in rat's hippocampal slices.

    Science.gov (United States)

    Chen, Ting; Yang, Jiajia; Zhang, Hui; Ren, Guogang; Yang, Zhuo; Zhang, Tao

    2014-09-17

    The purpose of the study was to investigate the neurotoxic effect of multi-walled carbon nanotubes (MWCNTs) on the properties of glutamatergic synaptic transmission in rat's hippocampal slices using whole-cell patch clamp technique. The amplitude and frequency of excitatory postsynaptic current (EPSC) were accessed on the hippocampal pyramidal neurons. The alterations of glutamatergic synaptic transmission in CA3-CA1 were examined by measuring both the amplitude of evoked excitatory postsynaptic current (eEPSC) and paired-pulse ratio (PPR). The data showed that the amplitude of either spontaneous excitatory postsynaptic current (sEPSC) or miniature excitatory postsynaptic current (mEPSC) was significantly inhibited by 1 μg/mL MWCNTs. However, it was found that there was a trend of different change on the frequency index. When 1 μg/mL MWCNTs was applied, there were a decreased frequency of mEPSC and an increased frequency of sEPSC, which might be due to the effect of action potential. Furthermore, the amplitudes of eEPSC at CA3-CA1 synapses were remarkably decreased. And the mean amplitude of AMPAR-mediated eEPSC was significantly reduced as well. Meanwhile, a majority of PPRs data were greater than one. There were no significant differences of PPRs between control and MWCNTs states, but an increased trend of paired-pulse facilitation was found. These results suggested that MWCNT markedly inhibited hippocampal CA1 glutamatergic synaptic transmission in vitro, which provided new insights into the MWCNT toxicology on CNS at cellular level.

  1. Frequency-dependent signal processing in apical dendrites of hippocampal CA1 pyramidal cells.

    Science.gov (United States)

    Watanabe, H; Tsubokawa, H; Tsukada, M; Aihara, T

    2014-10-10

    Depending on an animal's behavioral state, hippocampal CA1 pyramidal cells receive distinct patterns of excitatory and inhibitory synaptic inputs. The time-dependent changes in the frequencies of these inputs and the nonuniform distribution of voltage-gated channels lead to dynamic fluctuations in membrane conductance. In this study, using a whole-cell patch-clamp method, we attempted to record and analyze the frequency dependencies of membrane responsiveness in Wistar rat hippocampal CA1 pyramidal cells following noise current injection directly into dendrites and somata under pharmacological blockade of all synaptic inputs. To estimate the frequency-dependent properties of membrane potential, membrane impedance was determined from the voltage response divided by the input current in the frequency domain. The cell membrane of most neurons showed low-pass filtering properties in all regions. In particular, the properties were strongly expressed in the somata or proximal dendrites. Moreover, the data revealed nonuniform distribution of dendritic impedance, which was high in the intermediate segment of the apical dendritic shaft (∼220-260μm from the soma). The low-pass filtering properties in the apical dendrites were more enhanced by membrane depolarization than those in the somata. Coherence spectral analysis revealed high coherence between the input signal and the output voltage response in the theta-gamma frequency range, and large lags emerged in the distal dendrites in the gamma frequency range. Our results suggest that apical dendrites of hippocampal CA1 pyramidal cells integrate synaptic inputs according to the frequency components of the input signal along the dendritic segments receiving the inputs.

  2. Neutron diffraction studies on Ca1-BaZr4P6O24 solid solutions

    Indian Academy of Sciences (India)

    S N Achary; O D Jayakumar; S J Patwe; A B Shinde; P S R Krishna; S K Kulshreshtha; A K Tyagi

    2008-11-01

    Herein we report the results of detailed crystallographic studies of Ca1-BaZr4P6O24 compositions from combined Rietveld refinements of powder X-ray and neutron diffraction data. All the studied compositions crystallize in rhombohedral lattice (space group R-3 No. 148). A continuous solid solution is concluded from the systematic variation of unit cell parameters. The variation of unit cell parameters with the composition indicates decreasing trend in parameter with increasing Ba2+ concentration contrast to an increasing trend in parameter.

  3. Presynaptic kainate receptors that enhance the release of GABA on CA1 hippocampal interneurons.

    Science.gov (United States)

    Cossart, R; Tyzio, R; Dinocourt, C; Esclapez, M; Hirsch, J C; Ben-Ari, Y; Bernard, C

    2001-02-01

    We report that kainate receptors are present on presynaptic GABAergic terminals contacting interneurons and that their activation increases GABA release. Application of kainate increased the frequency of miniature inhibitory postsynaptic currents recorded in CA1 interneurons. Local applications of glutamate but not of AMPA or NMDA also increased GABA quantal release. Application of kainate as well as synaptically released glutamate reduced the number of failures of GABAergic neurotransmission between interneurons. Thus, activation of presynaptic kainate receptors increases the probability of GABA release at interneuron-interneuron synapses. Glutamate may selectively control the communication between interneurons by increasing their mutual inhibition.

  4. Transhepatic perforation of the gallbladder: rare complication of a common disease

    Directory of Open Access Journals (Sweden)

    Shrestha KR

    2010-05-01

    Full Text Available Acute cholecystitis leading to gallbladder perforation is relatively common. However, transhepatic perforation of the gallbladder leading to biliary peritonitis is very rare. We present a rare case of biliary peritonitis caused by transhepatic perforation of the gallbladder.

  5. Perforator-to-perforator musculocutaneous anterolateral thigh flap for reconstruction of a lumbosacral defect using the lumbar artery perforator as recipient vessel.

    Science.gov (United States)

    Mureau, Marc A M; Hofer, Stefan O P

    2008-05-01

    Reconstruction of large-sized lumbosacral or sacral defects often is not possible using local or regional flaps, making the use of free flaps necessary. However, the difficulty of any microsurgical procedure in this region is complicated by the need to search for potential recipient vessels to revascularize the flap. In the present case, a free musculocutaneous anterolateral thigh flap to cover a large-sized and deep lumbosacral defect was used. Arterial anastomosis was performed, connecting the cutaneous anterolateral thigh (ALT) perforator to the perforator of the second lumbar artery. In this fashion, the arterial circulation through the flap was flowing reversely through the muscle. The concomitant vein of the descending branch of the lateral circumflex femoral artery was hooked up to the thoracodorsal vein using a long interposition vein graft because the perforator of the second lumbar vein was too small. Postoperative healing was uneventful. In conclusion, a successful reconstruction of a lumbar defect has shown that local perforators in the lumbar area may be accessible for easier perforator-to-perforator anastomoses and that the muscular part of the musculocutaneous ALT flap can survive on retrograde arterial perfusion from a perforator of the skin island.

  6. [Case report: intestinal perforation by foreign body].

    Science.gov (United States)

    Martínez Portilla, Karol A; Zubiri, Cecilia; Balcarce, Norma; Zosi, Anabella; Chereau, Clara I

    2017-02-01

    Accidental ingestion of foreign bodies in childhood is a common event that rarely requires interventional management and presents very few complications involving surgical treatment. We present a clinical case of a 10 month old infant, without abdominal manifestations, in whom it was incidentally found a foreign radiopaque body of 7 cm in length in the abdomen, compatible with a screw. It was not possible to extract it by endoscopy. Therefore, it was necessary to perform surgery and a perforation of the second and third portion of the duodenum was encountered.

  7. Bladder Perforation Secondary to Primary Systemic Amyloidosis

    Directory of Open Access Journals (Sweden)

    Christopher J. Dru

    2014-01-01

    Full Text Available Amyloidosis is a disorder of protein folding characterized by extracellular aggregation and deposition of amyloid protein fibrils. Light-chain amyloidosis, also known as primary systemic amyloidosis, is the most common form of the disease. We present a case of an 84-year-old male with a history of systemic primary amyloidosis causing genitourinary, cardiac, and autonomic dysfunction who presented with hematuria and hypotension secondary to bladder perforation. He underwent open repair of a large extraperitoneal bladder defect. He ultimately died as a result of medical complications from his disease.

  8. Perforation rate in acute appendicitis: association with different risk facotrs

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    B. Khorasani

    2006-08-01

    Full Text Available Background: The early diagnosis of acute appendicitis before progression to gangrene or abscess formation is recognized as important to minimize morbidity from this common disease process. The aim of this study was to assess the value of different risk factors in the diagnosis of perforation. Methods: This descriptive-analytic and retrospective study was conducted to investigate epidemiological characteristics in patients with perforated and non-perforated appendicitis. A series of 1311 patients who were operated on for acute appendicitis between years 1380-1382 in Shahid Beheshti and Yahya-nejad hospitals were reviewed.. Data gathered included age at operation, gender, care sought prior to admission for appendectomy including antibiotic and analgesic therapy, time of presentation in the year, duration of symptoms, signs and symptoms at the time of admission, and the patient’s living area. Results: One hundred twenty one of 1311 patients (9% had perforated appendicitis and 1190 patients (91% had unperforated appendicitis. Presentation and referral in the first 6-month was associated with higher perforation rate. Patients from rural area showed a higher rate of perforations. The perforation rate was significantly higher in elderly patients (>65 year. When the duration of symptoms was more than 12 hours at presentation, the risk of perforation showed a five-fold increase. 30.7% of perforated cases had used antibiotic or sedative before referring to the hospital. Conclusion: Appendiceal perforation continues to be a complication in patients with acute appendicitis and increased in the frequency as the age of the patients increase and the duration of symptoms lengthen. We also found that the perforation rate is higher in patients from rural area and in whom present in the first 6-month of the year, a finding that was not reported so far.

  9. The value of CT in detecting pathologic bowel perforation

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jong Wun; Shin, Joo Yong; Kim, Hong; Rhee, Chang Soo; Lee, Sung Moon; Joo, Yang Goo; Suh, Soo Jhi [Keimyung Univ. School of Medicine, Taegu (Korea, Republic of)

    1997-10-01

    To evaluate the usefulness of CT for assessing the location and cause of pathologic gastrointestinal perforation. A retrospective analysis of abdominal CT was performed in 27 perforations of 26 patients with underlying gastrointestinal pathology. Fifteen benign and 12 malignant perforations consisted of five gastric cancers, one gastric ulcer, ten duodenal bulb ulcers. two bowel adhesions, one jejunal metastasis from lung cancer, one ileocolic Crohn's disease, one radiation colitis and six colon cancers. CT scans were evaluated for (1) diagnosis of bowel perforation, (2) assessment of the cause and site of perforation, and, in particular, differentiation between benignancy and malignancy, and (3) complications and their extent. CT easily detected varying amounts of free air or fluid collection, and infiltration or abscess formation adjacent to the main lesion, and the diagnosis of gastrointestinal perforation was therefore easy. In 11 of the 12 malignancies (92%), primary tumor was diagnosed, but detection of the site of perforation was possible in only seven cases(7/12, 58%). The 15 benign lesions revealed nonspecific CT findings, and the perforation site could be presumed in six (6/15, 40%). In one case of Crohn's disease, the primary cause was visualized. Among six colonic cancers, four pericolic abscesses and two fistulas to adjacent organs were found, but there was no evidence of diffuse peritonitis. CT was helpful to lead to optimal treatment of pathologic gastrointestinal On CT the detectability of perforation, primary benign or malignant lesion, perforation site and extent of complication was high, and this modality was therefore a useful indicator of the optimal treatment for pathologic gastrointestinal perforations.=20.

  10. Role of hippocampal CA1 area gap junction channels on morphine state-dependent learning.

    Science.gov (United States)

    Beheshti, Siamak; Hosseini, Seyyed Akbar Mir Seyyed; Noorbakhshnia, Maryam; Eivani, Mehdi

    2014-12-15

    Morphine produces a state dependent learning. The hippocampus is involved in this kind of learning. Gap junctions (GJs) are involved in some of the effects of morphine and exist in different areas of the hippocampus. We investigated the effects of blocking GJ channels of the hippocampal CA1 area, by means of pre-test bilateral injection of carbenoxolone (CBX), on morphine state dependent learning, using a passive avoidance task. Post-training subcutaneous administrations of morphine (0.5, 2.5, 5 and 7.5 mg/kg) dose-dependently impaired memory retrieval. Pre-test administration of morphine (0.5, 2.5, 5 and 7.5 mg/kg) induced a state-dependent retrieval of the memory acquired under post-training morphine influence. Pre-test injections of CBX (25, 75 and 150 nM) dose dependently prevented memory retrieval by post-training (7.5 mg/kg) and pre-test (0.5, 2.5, 5, 7.5 mg/kg) injections of morphine. The results suggest that intercellular coupling via GJ channels of the hippocampal CA1 area modulates morphine state dependent learning.

  11. Cytomorphometric changes in hippocampal CA1 neurons exposed to simulated microgravity using rats as model

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    Amit eRanjan

    2014-05-01

    Full Text Available Microgravity and sleep loss lead to cognitive and learning deficits. These behavioral alterations are likely to be associated with cytomorphological changes and loss of neurons. To understand the phenomenon, we exposed rats (225-275g to 14 days simulated microgravity (SMg and compared its effects on CA1 hippocampal neuronal plasticity, with that of normal cage control rats. We observed that the mean area, perimeter, synaptic cleft and length of active zone of CA1 hippocampal neurons significantly decreased while dendritic arborization and number of spines significantly increased in SMg group as compared with controls. The mean thickness of the post synaptic density and total dendritic length remained unaltered. The changes may be a compensatory effect induced by exposure to microgravity; however, the effects may be transient or permanent, which need further study. These findings may be useful for designing effective prevention for those, including the astronauts, exposed to microgravity. Further, subject to confirmation we propose that SMg exposure might be useful for recovery of stroke patients.

  12. Metrifonate decreases sI(AHP) in CA1 pyramidal neurons in vitro.

    Science.gov (United States)

    Power, J M; Oh, M M; Disterhoft, J F

    2001-01-01

    Metrifonate, a cholinesterase inhibitor, has been shown to enhance learning in aging rabbits and rats, and to alleviate the cognitive deficits observed in Alzheimer's disease patients. We have previously determined that bath application of metrifonate reduces the spike frequency adaptation and postburst afterhyperpolarization (AHP) in rabbit CA1 pyramidal neurons in vitro using sharp electrode current-clamp recording. The postburst AHP and accommodation observed in current clamp are the result of four slow outward potassium currents (sI(AHP), I(AHP), I(M), and I(C)) and the hyperpolarization activated mixed cation current, I(h). We recorded from visually identified CA1 hippocampal pyramidal neurons in vitro using whole cell voltage-clamp technique to better isolate and characterize which component currents of the AHP are affected by metrifonate. We observed an age-related enhancement of the slow component of the AHP tail current (sI(AHP)), but not of the fast decaying component of the AHP tail current (I(AHP), I(M), and I(C)). Bath perfusion of metrifonate reduced sI(AHP) at concentrations that cause a reduction of the AHP and accommodation in current-clamp recordings, with no apparent reduction of I(AHP), I(M), and I(C). The functional consequences of metrifonate administration are apparently mediated solely through modulation of the sI(AHP).

  13. Saikosaponin a Enhances Transient Inactivating Potassium Current in Rat Hippocampal CA1 Neurons

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    Wei Xie

    2013-01-01

    Full Text Available Saikosaponin a (SSa, a main constituent of the Chinese herb Bupleurum chinense DC., has been demonstrated to have antiepileptic activity. Recent studies have shown that SSa could inhibit NMDA receptor current and persistent sodium current. However, the effects of SSa on potassium (K+ currents remain unclear. In this study, we tested the effect of SSa on 4AP-induced epileptiform discharges and K+ currents in CA1 neurons of rat hippocampal slices. We found that SSa significantly inhibited epileptiform discharges frequency and duration in hippocampal CA1 neurons in the 4AP seizure model in a dose-dependent manner with an IC50 of 0.7 μM. SSa effectively increased the amplitude of ITotal and IA, significantly negative-shifted the activation curve, and positive-shifted steady-state curve of IA. However, SSa induced no significant changes in the amplitude and activation curve of IK. In addition, SSa significantly increased the amplitude of 4AP-sensitive K+ current, while there was no significant change in the amplitude of TEA-sensitive K+ current. Together, our data indicate that SSa inhibits epileptiform discharges induced by 4AP in a dose-dependent manner and that SSa exerts selectively enhancing effects on IA. These increases in IA may contribute to the anticonvulsant mechanisms of SSa.

  14. Pycnogenol protects CA3-CA1 synaptic function in a rat model of traumatic brain injury.

    Science.gov (United States)

    Norris, Christopher M; Sompol, Pradoldej; Roberts, Kelly N; Ansari, Mubeen; Scheff, Stephen W

    2016-02-01

    Pycnogenol (PYC) is a patented mix of bioflavonoids with potent anti-oxidant and anti-inflammatory properties. Previously, we showed that PYC administration to rats within hours after a controlled cortical impact (CCI) injury significantly protects against the loss of several synaptic proteins in the hippocampus. Here, we investigated the effects of PYC on CA3-CA1 synaptic function following CCI. Adult Sprague-Dawley rats received an ipsilateral CCI injury followed 15 min later by intravenous injection of saline vehicle or PYC (10 mg/kg). Hippocampal slices from the injured (ipsilateral) and uninjured (contralateral) hemispheres were prepared at seven and fourteen days post-CCI for electrophysiological analyses of CA3-CA1 synaptic function and induction of long-term depression (LTD). Basal synaptic strength was impaired in slices from the ipsilateral, relative to the contralateral, hemisphere at seven days post-CCI and susceptibility to LTD was enhanced in the ipsilateral hemisphere at both post-injury timepoints. No interhemispheric differences in basal synaptic strength or LTD induction were observed in rats treated with PYC. The results show that PYC preserves synaptic function after CCI and provides further rationale for investigating the use of PYC as a therapeutic in humans suffering from neurotrauma.

  15. Neural Androgen Receptor Deletion Impairs the Temporal Processing of Objects and Hippocampal CA1-Dependent Mechanisms.

    Directory of Open Access Journals (Sweden)

    Marie Picot

    Full Text Available We studied the role of testosterone, mediated by the androgen receptor (AR, in modulating temporal order memory for visual objects. For this purpose, we used male mice lacking AR specifically in the nervous system. Control and mutant males were gonadectomized at adulthood and supplemented with equivalent amounts of testosterone in order to normalize their hormonal levels. We found that neural AR deletion selectively impaired the processing of temporal information for visual objects, without affecting classical object recognition or anxiety-like behavior and circulating corticosterone levels, which remained similar to those in control males. Thus, mutant males were unable to discriminate between the most recently seen object and previously seen objects, whereas their control littermates showed more interest in exploring previously seen objects. Because the hippocampal CA1 area has been associated with temporal memory for visual objects, we investigated whether neural AR deletion altered the functionality of this region. Electrophysiological analysis showed that neural AR deletion affected basal glutamate synaptic transmission and decreased the magnitude of N-methyl-D-aspartate receptor (NMDAR activation and high-frequency stimulation-induced long-term potentiation. The impairment of NMDAR function was not due to changes in protein levels of receptor. These results provide the first evidence for the modulation of temporal processing of information for visual objects by androgens, via AR activation, possibly through regulation of NMDAR signaling in the CA1 area in male mice.

  16. Neural Androgen Receptor Deletion Impairs the Temporal Processing of Objects and Hippocampal CA1-Dependent Mechanisms.

    Science.gov (United States)

    Picot, Marie; Billard, Jean-Marie; Dombret, Carlos; Albac, Christelle; Karameh, Nida; Daumas, Stéphanie; Hardin-Pouzet, Hélène; Mhaouty-Kodja, Sakina

    2016-01-01

    We studied the role of testosterone, mediated by the androgen receptor (AR), in modulating temporal order memory for visual objects. For this purpose, we used male mice lacking AR specifically in the nervous system. Control and mutant males were gonadectomized at adulthood and supplemented with equivalent amounts of testosterone in order to normalize their hormonal levels. We found that neural AR deletion selectively impaired the processing of temporal information for visual objects, without affecting classical object recognition or anxiety-like behavior and circulating corticosterone levels, which remained similar to those in control males. Thus, mutant males were unable to discriminate between the most recently seen object and previously seen objects, whereas their control littermates showed more interest in exploring previously seen objects. Because the hippocampal CA1 area has been associated with temporal memory for visual objects, we investigated whether neural AR deletion altered the functionality of this region. Electrophysiological analysis showed that neural AR deletion affected basal glutamate synaptic transmission and decreased the magnitude of N-methyl-D-aspartate receptor (NMDAR) activation and high-frequency stimulation-induced long-term potentiation. The impairment of NMDAR function was not due to changes in protein levels of receptor. These results provide the first evidence for the modulation of temporal processing of information for visual objects by androgens, via AR activation, possibly through regulation of NMDAR signaling in the CA1 area in male mice.

  17. Cholinergic modulation differs between basal and apical dendritic excitation of hippocampal CA1 pyramidal cells.

    Science.gov (United States)

    Leung, L Stan; Péloquin, Pascal

    2010-08-01

    We hypothesize that endogenous cholinergic modulation of dendritic processing of hippocampal CA1 is layer specific, and it specifically enhances spike output resulting from basal as compared with the apical dendritic excitation. Laminar profiles of evoked field potentials were recorded in the CA1 area of urethane-anesthetized rats using multichannel silicon probes and analyzed as current source density. High-frequency stimulation of the pontis oralis (PnO) attenuated the midapical more than the basal or distal apical dendritic excitatory sink. Population spike (PS) and excitatory sink-PS potentiation resulting from basal dendritic excitation were facilitated, while the PS evoked by apical dendritic stimulation was attenuated by PnO stimulation. Perfusion of cholinergic agonist carbachol onto hippocampal slices in vitro also attenuated the apical more than the basal dendritic excitatory postsynaptic potentials. Excitatory sink attenuation and PS changes after PnO stimulation were blocked by systemic or local scopolamine and by intracerebroventricular (icv) M1 receptor antagonist pirenzepine but not by icv M2 receptor antagonist AFDX-116 or nicotinic antagonists. However, a hippocampal theta rhythm activated by PnO stimulation was blocked by systemic but not by local scopolamine. We conclude that endogenous acetylcholine mediates a stronger presynaptic inhibition of the midapical than basal and distal apical excitation mainly through M1 receptors.

  18. Developmental Changes in Hippocampal CA1 Single Neuron Firing and Theta Activity during Associative Learning

    Science.gov (United States)

    Kim, Jangjin; Goldsberry, Mary E.; Harmon, Thomas C.; Freeman, John H.

    2016-01-01

    Hippocampal development is thought to play a crucial role in the emergence of many forms of learning and memory, but ontogenetic changes in hippocampal activity during learning have not been examined thoroughly. We examined the ontogeny of hippocampal function by recording theta and single neuron activity from the dorsal hippocampal CA1 area while rat pups were trained in associative learning. Three different age groups [postnatal days (P)17-19, P21-23, and P24-26] were trained over six sessions using a tone conditioned stimulus (CS) and a periorbital stimulation unconditioned stimulus (US). Learning increased as a function of age, with the P21-23 and P24-26 groups learning faster than the P17-19 group. Age- and learning-related changes in both theta and single neuron activity were observed. CA1 pyramidal cells in the older age groups showed greater task-related activity than the P17-19 group during CS-US paired sessions. The proportion of trials with a significant theta (4–10 Hz) power change, the theta/delta ratio, and theta peak frequency also increased in an age-dependent manner. Finally, spike/theta phase-locking during the CS showed an age-related increase. The findings indicate substantial developmental changes in dorsal hippocampal function that may play a role in the ontogeny of learning and memory. PMID:27764172

  19. Ripple-associated high-firing interneurons in the hippocampal CA1 region

    Institute of Scientific and Technical Information of China (English)

    WANG Ying; ZHANG Lu; PAN JingWei; XIE Kun; LI ShiQi; WANG ZhiRu; LIN LongNian

    2008-01-01

    By simultaneously recording the activity of individual neurons and field potentials in freely behaving mice, we found two types of interneurons firing at high frequency in the hippocampal CA1 region,which had high correlations with characteristic sharp wave-associated ripple oscillations (100-250 Hz)during slow-wave sleep. The firing of these two types of interneurons highly synchronized with ripple oscillations during slow-wave sleep, with strongly increased firing rates corresponding to individual ripple episodes. Interneuron type Ⅰ had at most one spike in each sub-ripple cycle of ripple episodes and the peak firing rate was 310±33.17 Hz. Interneuron type Ⅱ had one or two spikes in each sub-ripple cycle and the peak firing rate was 410±47.61 Hz. During active exploration, their firing was phase locked to theta oscillations with the highest probability at the trough of theta wave. Both two types of interneurons increased transiently their firing rates responding to the startling shake stimuli. The results showed that these two types of high-frequency interneurone in the hippocsmpal CA1 region were involved in the modulation of the hippocampal neural network during different states.

  20. Space and time sequence and mosaicism of neurogenesis in hippocampal area CA1 in mice

    Energy Technology Data Exchange (ETDEWEB)

    Nazarevskaya, G.D.; Reznikov, K. Yu.

    1986-02-01

    The study of the times and sequence of neuron formation in various structures of the mammalian brain has made substantial progress thanks to the use of autoradiographic techniques, by which the germinative precursors of neurons can be tagged with tritium-thymidine and the subsequent fate of the labeled cells can be followed. The authors study the space and time sequence of neuron formation and look for the presence of mosaicism of neurogenesis in area CA1 of Ammon's horn of the mouse hippocampus, one of the most regularly arranged hippocampal areas. An analysis of the distribution of intensively labeled neurons in areas CA1 showed the presence of groups of intensively labeled neurons alternating with unlabeled and weakly labeled cells.. Mice receiving tritium-thymidine on the 13th-16th day of embryogenesis were most marked when the isotope was injected on the 14th-15th day of embroygeneisis. The investigation showed that a mosaic pattern of neurogenesis exists in the hippocampus, just as in the neocortex, and it can be regarded as the result of asynchronous production of neurons by local areas of the germinative zone, each of which constructs a radial segment of cortex.

  1. Ripple-associated high-firing interneurons in the hippocampal CA1 region

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    By simultaneously recording the activity of individual neurons and field potentials in freely behaving mice, we found two types of interneurons firing at high frequency in the hippocampal CA1 region, which had high correlations with characteristic sharp wave-associated ripple oscillations (100―250 Hz) during slow-wave sleep. The firing of these two types of interneurons highly synchronized with ripple oscillations during slow-wave sleep, with strongly increased firing rates corresponding to individual ripple episodes. Interneuron type I had at most one spike in each sub-ripple cycle of ripple episodes and the peak firing rate was 310±33.17 Hz. Interneuron type II had one or two spikes in each sub-ripple cycle and the peak firing rate was 410±47.61 Hz. During active exploration, their firing was phase locked to theta oscillations with the highest probability at the trough of theta wave. Both two types of interneurons increased transiently their firing rates responding to the startling shake stimuli. The results showed that these two types of high-frequency interneurons in the hippocampal CA1 region were involved in the modulation of the hippocampal neural network during different states.

  2. Somatosensory stimulation suppresses the excitability of pyramidal cells in the hippocampal CA1 region in rats

    Institute of Scientific and Technical Information of China (English)

    Yang Wang; Zhouyan Feng; Jing Wang; Xiaojing Zheng

    2014-01-01

    The hippocampal region of the brain is important for encoding environment inputs and memory formation. However, the underlying mechanisms are unclear. To investigate the behavior of indi-vidual neurons in response to somatosensory inputs in the hippocampal CA1 region, we recorded and analyzed changes in local ifeld potentials and the ifring rates of individual pyramidal cells and interneurons during tail clamping in urethane-anesthetized rats. We also explored the mechanisms underlying the neuronal responses. Somatosensory stimulation, in the form of tail clamping, chan-ged local ifeld potentials into theta rhythm-dominated waveforms, decreased the spike ifring of py-ramidal cells, and increased interneuron ifring. In addition, somatosensory stimulation attenuated orthodromic-evoked population spikes. These results suggest that somatosensory stimulation sup-presses the excitability of pyramidal cells in the hippocampal CA1 region. Increased inhibition by local interneurons might underlie this effect. These ifndings provide insight into the mechanisms of signal processing in the hippocampus and suggest that sensory stimulation might have thera-peutic potential for brain disorders associated with neuronal hyperexcitability.

  3. Activity-dependent upregulation of presynaptic kainate receptors at immature CA3-CA1 synapses.

    Science.gov (United States)

    Clarke, Vernon R J; Molchanova, Svetlana M; Hirvonen, Teemu; Taira, Tomi; Lauri, Sari E

    2014-12-10

    Presynaptic kainate-type glutamate receptors (KARs) regulate glutamate release probability and short-term plasticity in various areas of the brain. Here we show that long-term depression (LTD) in the area CA1 of neonatal rodent hippocampus is associated with an upregulation of tonic inhibitory KAR activity, which contributes to synaptic depression and causes a pronounced increase in short-term facilitation of transmission. This increased KAR function was mediated by high-affinity receptors and required activation of NMDA receptors, nitric oxide (NO) synthetase, and postsynaptic calcium signaling. In contrast, KAR activity was irreversibly downregulated in response to induction of long-term potentiation in a manner that depended on activation of the TrkB-receptor of BDNF. Both tonic KAR activity and its plasticity were restricted to early stages of synapse development and were lost in parallel with maturation of the network due to ongoing BDNF-TrkB signaling. These data show that presynaptic KARs are targets for activity-dependent modulation via diffusible messengers NO and BDNF, which enhance and depress tonic KAR activity at immature synapses, respectively. The plasticity of presynaptic KARs in the developing network allows nascent synapses to shape their response to incoming activity. In particular, upregulation of KAR function after LTD allows the synapse to preferentially pass high-frequency afferent activity. This can provide a potential rescue from synapse elimination by uncorrelated activity and also increase the computational dynamics of the developing CA3-CA1 circuitry.

  4. Molecular and electrophysiological characterization of GFP-expressing CA1 interneurons in GAD65-GFP mice.

    Directory of Open Access Journals (Sweden)

    Corette J Wierenga

    Full Text Available The use of transgenic mice in which subtypes of neurons are labeled with a fluorescent protein has greatly facilitated modern neuroscience research. GAD65-GFP mice, which have GABAergic interneurons labeled with GFP, are widely used in many research laboratories, although the properties of the labeled cells have not been studied in detail. Here we investigate these cells in the hippocampal area CA1 and show that they constitute ∼20% of interneurons in this area. The majority of them expresses either reelin (70±2% or vasoactive intestinal peptide (VIP; 15±2%, while expression of parvalbumin and somatostatin is virtually absent. This strongly suggests they originate from the caudal, and not the medial, ganglionic eminence. GFP-labeled interneurons can be subdivided according to the (partially overlapping expression of neuropeptide Y (42±3%, cholecystokinin (25±3%, calbindin (20±2% or calretinin (20±2%. Most of these subtypes (with the exception of calretinin-expressing interneurons target the dendrites of CA1 pyramidal cells. GFP-labeled interneurons mostly show delayed onset of firing around threshold, and regular firing with moderate frequency adaptation at more depolarized potentials.

  5. Disinhibition mediates a form of hippocampal long-term potentiation in area CA1.

    Directory of Open Access Journals (Sweden)

    Jake Ormond

    Full Text Available The hippocampus plays a central role in memory formation in the mammalian brain. Its ability to encode information is thought to depend on the plasticity of synaptic connections between neurons. In the pyramidal neurons constituting the primary hippocampal output to the cortex, located in area CA1, firing of presynaptic CA3 pyramidal neurons produces monosynaptic excitatory postsynaptic potentials (EPSPs followed rapidly by feedforward (disynaptic inhibitory postsynaptic potentials (IPSPs. Long-term potentiation (LTP of the monosynaptic glutamatergic inputs has become the leading model of synaptic plasticity, in part due to its dependence on NMDA receptors (NMDARs, required for spatial and temporal learning in intact animals. Using whole-cell recording in hippocampal slices from adult rats, we find that the efficacy of synaptic transmission from CA3 to CA1 can be enhanced without the induction of classic LTP at the glutamatergic inputs. Taking care not to directly stimulate inhibitory fibers, we show that the induction of GABAergic plasticity at feedforward inhibitory inputs results in the reduced shunting of excitatory currents, producing a long-term increase in the amplitude of Schaffer collateral-mediated postsynaptic potentials. Like classic LTP, disinhibition-mediated LTP requires NMDAR activation, suggesting a role in types of learning and memory attributed primarily to the former and raising the possibility of a previously unrecognized target for therapeutic intervention in disorders linked to memory deficits, as well as a potentially overlooked site of LTP expression in other areas of the brain.

  6. Dendritic development of hippocampal CA1 pyramidal cells in a neonatal hypoxia-ischemia injury model.

    Science.gov (United States)

    Zhao, Yan Dong; Ou, Shan; Cheng, Sai Yu; Xiao, Zhi; He, Wen Juan; Zhang, Jin Hai; Ruan, Huai Zhen

    2013-09-01

    It is believed that neonatal hypoxia-ischemia (HI) brain injury causes neuron loss and brain functional defects. However, the effect of HI brain injury on dendritic development of the remaining pyramidal cells of the hippocampus and the reaction of contralateral hippocampal neurons require further studies. The Morris water maze and Golgi-Cox staining were used to evaluate the learning and memory and dendritic morphology of pyramidal cells. The results of Golgi-Cox staining showed CA1 pyramidal neurons of HI injury models with fewer bifurcations and shorter dendrite length than the naive control group. The density of dendritic spines of hippocampal CA1 pyramidal neurons was significantly lower in the HI brain injury group than in controls. With respect to hippocampal function, the HI brain injury group presented cognitive deficits in the reference memory task and probe trail. In the HI group, the pyramidal cells of left hippocampus that did not experienced ischemia but did experience hypoxia had more complex dendrites and higher density of spine than the HI injury side and control. The functional implementation of injured hippocampus might depend mainly on the hypertrophy of contralateral hippocampus after HI brain injury. Corticosterone can partially prevent the hippocampal pyramidal cells from HI injury and reduce the difference of the bilateral hippocampus pyramidal cells, but there was no improvement in learning and memory.

  7. CB1介导△~9-THC抑制CA1区LTD的作用%CB1 modulates △~9-THC-induced inhibition of LTD in the CA1 area

    Institute of Scientific and Technical Information of China (English)

    杨红卫

    2009-01-01

    目的 探讨大麻素受体1(CB1)在四氢大麻酚(△~9-THC)抑制CA1区长时程抑制(LTD)中的作用.方法 在小鼠腹腔注射△~9-THC(10 mg/ks)或CB1受体的选择性抑制剂SR141716(SR,5 mg/kg)24 h后切片,在海马CA1区记录场电位EPSP.结果 ①给予低频电刺激(1 Hz 15 min)诱导CA1区LTD,△~9-THC可显著降低LTD(P0.05).结论 CB1受体介导△~9-THC抑制离体海马CA1区LTD的作用.

  8. Perforation af rectum med faekal peritonitis efter staplet haemorideoperation

    DEFF Research Database (Denmark)

    Beuke, Anna-Christina; Pedersen, Mark Ellebaek; Qvist, Niels

    2008-01-01

    Rectal perforation and faecal peritonitis after stapled operation for grade IV haemorrhoids is described. The complication is rare, but surgeons performing the procedure must be familiar with potential risk factors.......Rectal perforation and faecal peritonitis after stapled operation for grade IV haemorrhoids is described. The complication is rare, but surgeons performing the procedure must be familiar with potential risk factors....

  9. CLINICAL STUDY AND MANAGEMENT OF PERITONITIS SECONDARY TO GASTROINTESTINAL PERFORATION

    Directory of Open Access Journals (Sweden)

    Karbhari

    2014-03-01

    Full Text Available Perforation peritonitis is the most common surgical emergency in India. Peritonitis due to upper gastrointestinal tract perforation constitutes majority of these cases. Despite advances in surgical techniques, antimicrobial therapy and intensive care support, management of peritonitis continues to be highly demanding, difficult and complex. . In contrast to western countries where lower gastro-intestinal tract perforations predominate, upper gastro intestinal tract perforations constitute the majority of cases in India1. Earlier Rawlinson in the year 1727 was the first to give a clear description of the signs and symptom of gastric ulcer and peritonitis.2 MATERIALS AND METHODS: All patients having GI perforation admitted in all surgical units of Basaweshwar Teaching and General Hospital, Gulbarga were considered for the study. A total of 50 cases were studied over a period of 18 months from Dec 2009 to May 2011.Data was entered in the proforma made for the study and analyzed RESULTS &CONCLUSION: Patient group more than 50yrs were the most commonly affected group and duodenal ulcer perforation (60% was the most common. Males (92% were affected more than females. Most common symptom was vomiting (68%. Guarding and rigidity were present in 90% patients. Laparotomy with closure of the perforation with omental patch is the commonest operative management for perforated peptic ulcer. The overall mortality was 4%

  10. Taenia saginata: A Rare Cause of Gall Bladder Perforation

    Directory of Open Access Journals (Sweden)

    Suhail Yaqoob Hakeem

    2012-01-01

    Full Text Available We report a case of biliary peritonitis caused by gall bladder perforation due to Taenia saginata induced gangrenous cholecystitis. Although parasites are not unusual causes of biliary tract disorders, especially in disease endemic areas, but this is for the first time that Taenia saginata has been reported to cause gall bladder perforation.

  11. [Retroperitoneal perforations of the colon. Apropos of 2 cases].

    Science.gov (United States)

    Jurczak, F; Likholatnikov, D; Courant, O; Hamy, A; Visset, J; Paineau, J

    1994-01-01

    The retroperitoneal perforation of the colon is rare and our observations illustrate its two modes of revelation: a retroperitoneal suppuration; it must be traited quickly in order to decrease the mortality. Note that the abscess of the thigh is exceptional. Retroperitoneal perforations during colonoscopy whose treatment (initially medical) become surgical if there is no clinical improvement.

  12. A rare manifestation of perforated diverticulitis: parastomal subcutaneous abscess.

    NARCIS (Netherlands)

    Peters, J.H.; Bleichrodt, R.P.; Goor, H. van

    2003-01-01

    Perforation is a serious complication of diverticular disease. The sigmoid is the main affected anatomic site of perforated diverticulitis and sigmoid resection followed either by Hartmann procedure or primary anastomosis are the standard surgical approaches. Surgery, however, does not cure divertic

  13. Computed Tomography Features of Spontaneously Perforated Pyometra: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.S.; Tan, C.K.; Mak, C.W.; Chia, C.C.; Kuo, C.Y.; Yu, W.L. [Chi-Mei Medical Center, Tainan, Taiwan (China). Depts. of Intensive Care Medicine, Radiology, Obstetrics and Gynecology, and Surgery

    2006-03-15

    Spontaneous perforation of pyometra is an extremely rare emergent gynecologic disease. We report a 73-year-old woman with a spontaneously perforated pyometra presenting with acute abdomen in the emergency department. A dedicated computed tomography examination of the abdominal and pelvic regions revealed the diagnosis. The patient recovered well after surgical intervention and antibiotic treatment.

  14. The "stamp method" : a new treatment for perforated peptic ulcer?

    NARCIS (Netherlands)

    Bertleff, MJOE; Liem, RSB; Robinson, PH; Bonjer, HJ; Lange, JF; Bartels, H.; van der Werf, J.F.A.

    2006-01-01

    Background: The aim of this study was to develop a simple method for closure of a perforated peptic ulcer, making it more accessible for laparoscopic surgery. Methods: An experimental pilot study was performed using five male Wistar rats. The perforation was closed by a bioabsorbable patch made of l

  15. The Versatile Extended Thoracodorsal Artery Perforator Flap for Breast Reconstruction

    DEFF Research Database (Denmark)

    Jacobs, Jordan; Børsen-Koch, Mikkel; Gunnarsson, Gudjon Leifur;

    2016-01-01

    BACKGROUND: The thoracodorsal artery perforator (TAP) flap is a versatile tool that can be used to reconstruct the breast. The authors use preoperative perforator mapping using color Doppler ultrasonography and present a safe, efficient harvesting technique to demonstrate reliable use of the TAP...

  16. Perforated peptic ulcer disease: A review of history and treatment

    NARCIS (Netherlands)

    M.J.O.E. Bertleff (Marietta); J.F. Lange (Johan)

    2010-01-01

    textabstractBackground: In the last one hundred years much has been written on peptic ulcer disease and the treatment options for one of its most common complications: perforation. The reason for reviewing the literature was evaluating most common ideas on how to treat perforated peptic ulcers (PPU)

  17. Directional bending wave propagation in periodically perforated plates

    DEFF Research Database (Denmark)

    Andreassen, Erik; Manktelow, Kevin; Ruzzene, Massimo

    2015-01-01

    We report on the investigation of wave propagation in a periodically perforated plate. A unit cell with double-C perforations is selected as a test article suitable to investigate two-dimensional dispersion characteristics, group velocities, and internal resonances. A numerical model, formulated ...

  18. Photoelastic stress analysis in perforated (Rochette) resin bonded bridge design.

    Science.gov (United States)

    Ziada, H M; Orr, J F; Benington, I C

    2000-05-01

    Rochette described the perforated cast metal bonded design for splinting periodontally compromised teeth. The design was later used for replacing missing teeth. The main causes of failure of the perforated (Rochette) type design were attributed to inappropriate case selection and erosion of the composite from perforations. The aim of this study was to analyse the effect of stress magnitude and direction on failure of perforated resin bonded bridges (RBBs). The objective was to compare stress magnitudes in this design with those reported on the non-perforated RBBs. Photoelastic modelling materials were selected to represent the relative stiffnesses of a posterior mandibular and an anterior maxillary perforated (Rochette) type design. The sizes of the models were scaled to x 2.5 in order to enhance visual analysis of the stress patterns. Stress magnitudes were quantified from isochromatic fringes and stress directions were evaluated from stress trajectories. These revealed a high-stress concentration around the perforations, particularly for those at the proximo-lingual/palatal (connector) areas. This experimental study revealed that the main reason for failure of Rochette designs is deformation at the perforations.

  19. BN-coated Ca(1-x)Sr(x)S:Eu solid-solution nanowires with tunable red light emission.

    Science.gov (United States)

    Lin, Jing; Huang, Yang; Mi, Jiao; Zhang, Xinghua; Lu, Zunming; Xu, Xuewen; Fan, Ying; Zou, Jin; Tang, Chengchun

    2013-10-11

    We report on the controlled growth of novel BN-coated Ca(1-x)Sr(x)S:Eu nanowires via a solid-liquid-solid process. The Ca(1-x)Sr(x)S solid solution forms as one-dimensional nanowires and has been coated with homogeneous protective BN nanolayers. The structure and luminescence properties of this new nanocomposite have been systematically investigated. High-spatial-resolution cathodoluminescence investigations reveal that effective red color tuning has been achieved by tailoring the composition of the Ca(1-x)Sr(x)S nanowires. Moreover, codoping of Ce(3+) and Eu(2+) in the CaS nanowire can induce energy transfer in the matrix and make it possible to obtain enhanced orange color in the nanowires. The BN-coated Ca(1-x)Sr(x)S:Eu solid-solution nanowires are envisaged to be valuable red-emitting nanophosphors and useful in advanced nanodevices and white LEDs.

  20. CFD Simulations of Oscillating Flow around Solid and Perforated Plates

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Damping plates have been used for truss spars in gulf of Mexico to reduce the heave motions. The plates are usually perforated with holes for the passage of marine risers, but the effects of the perforation have not been examined thoroughly. In the present study, a computational fluid dynamics investigation into the hydrodynamic forces is carried out by using FLUENT, which is on two-dimensional perforated plates with varying degrees of perforation in oscillating flow under small Keulegan-Carpenter (KC) number. The numerical results of the hydrodynamic coefficients are presented. The effects of both the perforation ratio (PR) and KC number on the hydrodynamic coefficients of the plates are discussed. Some results of the simulated flow patterns around the plates were also given and discussed.

  1. Features of Flow Past Square Cylinder with a Perforated Plate

    Institute of Scientific and Technical Information of China (English)

    汪健生; 徐亚坤; 程浩杰

    2016-01-01

    A numerical investigation was performed on the reduction of the fluid forces acting on the square cylin-der in the laminar flow regime with a perforated plate. The effects of geometric parameters such as the distance between the square cylinder and the perforated plate on the wake of the square cylinder were discussed. Further-more, the flow characteristics such as the drag coefficient, lift coefficient, Strouhal number and flow pattern were obtained. It can be concluded that the drag force of the square cylinder reduces to some extent due to the addition of the perforated plate. The flow structure varies when the perforated plate is located behind the square cylinder. Moreover, the recirculation zone augments with the increase ofL/D, and the vortex trace on the upper and lower surface of the square cylinder moves gradually backwards until a stable recirculation zone formed between the square cylinder and the perforated plate.

  2. Esophageal Perforation due to Transesophageal Echocardiogram: New Endoscopic Clip Treatment

    Directory of Open Access Journals (Sweden)

    John Robotis

    2014-07-01

    Full Text Available Esophageal perforation due to transesophageal echocardiogram (TEE during cardiac surgery is rare. A 72-year-old female underwent TEE during an operation for aortic valve replacement. Further, the patient presented hematemesis. Gastroscopy revealed an esophageal bleeding ulcer. Endoscopic therapy was successful. Although a CT scan excluded perforation, the patient became febrile, and a second gastroscopy revealed a big perforation at the site of ulcer. The patient's clinical condition required endoscopic intervention with a new OTSC® clip (Ovesco Endoscopy, Tübingen, Germany. The perforation was successfully sealed. The patient remained on intravenous antibiotics, proton pump inhibitors and parenteral nutrition for few days, followed by enteral feeding. She was discharged fully recovered 3 months later. We clearly demonstrate an effective, less invasive treatment of an esophageal perforation with a new endoscopic clip.

  3. Perforated jejunal diverticulum in the use of mycophenolate mofetil

    Directory of Open Access Journals (Sweden)

    Charat Thongprayoon

    2014-01-01

    Full Text Available Context: Jejunal diverticulosis is a rare disease. Common acute complications include diverticulitis, intestinal obstruction, bleeding and perforation. Gastrointestinal tract perorations have also been rarely observed in the use of mycophenolate mofetil. Case Report: We report a 44-year-old man with end-stage renal disease post failed kidney transplant on low-dose mycophenolate mofetil who presented with acute onset of abdominal pain. He was successfully given the diagnosis of perforated jejunal diverticulum. The patient successfully underwent a segmental jejunal resection and anastomosis. He unfortunately developed a recurrent jejunal perforation a month later and again had the second segmental jejunal resection operation. Mycophenolate mofetil then was discontinued. Conclusion: The present case illustrates jejunal diverticulum perforation in the use of mycophenolate mofetil. Physicians should increase the awareness of this association of perforated jejunal diverticulum in patients using mycophenolate mofetil.

  4. Spontaneous Uterine Perforation due to Pyometra Presenting as Acute Abdomen

    Directory of Open Access Journals (Sweden)

    Loabat Geranpayeh

    2006-01-01

    Full Text Available Spontaneous perforation of the uterus is rare, its incidence being about 0.01%–0.05%. We report a rare case of diffuse peritonitis caused by spontaneously perforated pyometra. A 63-year-old woman with severe abdominal pain was admitted to our hospital. Laparotomy was performed because of the suspicion of gastrointestinal perforation with generalized peritonitis. At laparotomy, about 900 mL of pus was found in the peritoneal cavity. There were no abnormal findings in the alimentary tract, liver, or gallbladder. A total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. Pathological investigation of the surgical specimen revealed endometritis and myometritis of the uterus; but there was no evidence of malignancy, and the cervical canal was patent. Although spontaneously perforated pyometra is rare, a perforated pyometra should therefore also be considered when elderly women present with acute abdominal pain.

  5. Pneumoscrotum: A rare manifestation of perforation associated with therapeutic colonoscopy

    Institute of Scientific and Technical Information of China (English)

    Kuang-I Fu; Takahiro Fujimori; Yasushi Sano; Shigeharu Kato; Takahiro Fujii; Masanori Sugito; Masato Ono; Norio Saito; Kiyotaka Kawashima; Shigeaki Yoshida

    2005-01-01

    Pneumoscrotum is uncommon and also rarely reported as a complication associated with colonic perforation. A case of colonic perforation in delayed fashion associated with EMR, revealed by pneumoscrotum, is reported and the associated literatures are reviewed. A 52-year-old male received piecemeal EMR for a laterally spreading tumor 35 mm in size in our hospital. He complained of enlargement of the scrotum and revisited our hospital the day after the procedure. A diagnosis of pneumoscrotum was made, and as most such cases have been reported to be associated with pneumoperitoneum, colonic perforation was suspected. Free air but no fluid collection was found by abdominal computed tomography, and delayed colonic perforation was diagnosed. However, as there were no clinical signs of peritoneal irritation,conservative treatment was administered and the patient recovered uneventfully. Pneumoscrotum could be a sign of colonic perforation after EMR, and treatment should be carefully chosen.

  6. Sodium currents in isolated rat CA1 neurons after kindling epileptogenesis.

    Science.gov (United States)

    Vreugdenhil, M; Faas, G C; Wadman, W J

    1998-09-01

    Cellular excitability of CA1 neurons from a kindled focus in the rat hippocampus is persistently increased. The changes in the underlying voltage-dependent sodium current were characterized under whole-cell voltage-clamp conditions. We compared sodium currents in acutely isolated CA1 neurons from kindled rats with those in matched controls, one day and five weeks after cessation of kindling stimulations. The sodium current in CA1 neurons was tetrodotoxin sensitive and inactivated completely with two time-constants. In 97 cells from control rats, the current evoked at -20 mV consisted of a fast-inactivating component of 3.8 +/- 0.2 nA which decayed with a time-constant of 1.0 +/- 0.1 ms, and a slow-inactivating component of 1.2 +/- 0.1 nA with a time-constant of 3.6 +/- 0.1 ms. The potential of half-maximal inactivation was -72.2 +/- 1.0 mV for the fast-inactivating component and -63.2 +/- 1.0 mV for the slow-inactivating component. The time-constant of recovery at -80 mV was 14.1 +/- 0.4 ms for the fast-inactivating component and 9.3 +/- 0.4 ms for the slow-inactivating component. One day after kindling, the voltage dependence of inactivation of the slow-inactivating and the fast-inactivating component was shifted in the depolarizing direction (3.2 +/- 1.3 and 3.0 +/- 1.3 mV, respectively). The voltage dependence of recovery from inactivation was shifted in the same direction. Five weeks after kindling, the shift in voltage dependence of inactivation was (3.3 +/- 1.2 and 2.9 +/- 1.2 mV, respectively) and was accompanied by a 20% increase in sodium current amplitude. The voltage-dependent activation was not different after kindling. The changes in sodium current inactivation will increase the number of channels available for activation and may enhance the maximum firing rate. This implies that the changes in sodium current inactivation will contribute to the enhanced excitability of pyramidal neurons observed after kindling.

  7. Feedforward Inhibition Underlies the Propagation of Cholinergically Induced Gamma Oscillations from Hippocampal CA3 to CA1

    OpenAIRE

    Zemankovics, Rita; Veres, Judit M.; Oren, Iris; Hájos, Norbert

    2013-01-01

    Gamma frequency (30–80 Hz) oscillations are implicated in memory processing. Such rhythmic activity can be generated intrinsically in the CA3 region of the hippocampus from where it can propagate to the CA1 area. To uncover the synaptic mechanisms underlying the intrahippocampal spread of gamma oscillations, we recorded local field potentials, as well as action potentials and synaptic currents in anatomically identified CA1 and CA3 neurons during carbachol-induced gamma oscillations in mouse ...

  8. Extrinsic and local glutamatergic inputs of the rat hippocampal CA1 area differentially innervate pyramidal cells and interneurons.

    Science.gov (United States)

    Takács, Virág T; Klausberger, Thomas; Somogyi, Peter; Freund, Tamás F; Gulyás, Attila I

    2012-06-01

    The two main glutamatergic pathways to the CA1 area, the Schaffer collateral/commissural input and the entorhinal fibers, as well as the local axons of CA1 pyramidal cells innervate both pyramidal cells and interneurons. To determine whether these inputs differ in their weights of activating GABAergic circuits, we have studied the relative proportion of pyramidal cells and interneurons among their postsynaptic targets in serial electron microscopic sections. Local axons of CA1 pyramidal cells, intracellularly labeled in vitro or in vivo, innervated a relatively high proportion of interneuronal postsynaptic targets (65.9 and 53.8%, in vitro and in vivo, respectively) in stratum (str.) oriens and alveus. In contrast, axons of in vitro labeled CA3 pyramidal cells in str. oriens and str. radiatum of the CA1 area made synaptic junctions predominantly with pyramidal cell spines (92.9%). The postsynaptic targets of anterogradely labeled medial entorhinal cortical boutons in CA1 str. lacunosum-moleculare were primarily pyramidal neuron dendritic spines and shafts (90.8%). The alvear group of the entorhinal afferents, traversing str. oriens, str. pyramidale, and str. radiatum showed a higher preference for innervating GABAergic cells (21.3%), particularly in str. oriens/alveus. These data demonstrate that different glutamatergic pathways innervate CA1 GABAergic cells to different extents. The results suggest that the numerically smaller CA1 local axonal inputs together with the alvear part of the entorhinal input preferentially act on GABAergic interneurons in contrast to the CA3, or the entorhinal input in str. lacunosum-moleculare. The results highlight differences in the postsynaptic target selection of the feed-forward versus recurrent glutamatergic inputs to the CA1 and CA3 areas.

  9. Action Potential Modulation in CA1 Pyramidal Neuron Axons Facilitates OLM Interneuron Activation in Recurrent Inhibitory Microcircuits of Rat Hippocampus

    OpenAIRE

    Sooyun Kim

    2014-01-01

    Oriens-lacunosum moleculare (O-LM) interneurons in the CA1 region of the hippocampus play a key role in feedback inhibition and in the control of network activity. However, how these cells are efficiently activated in the network remains unclear. To address this question, I performed recordings from CA1 pyramidal neuron axons, the presynaptic fibers that provide feedback innervation of these interneurons. Two forms of axonal action potential (AP) modulation were identified. First, repetitive ...

  10. Dopamine regulates intrinsic excitability thereby gating successful induction of spike timing-dependent plasticity in CA1 of the hippocampus.

    Science.gov (United States)

    Edelmann, Elke; Lessmann, Volkmar

    2013-01-01

    Long-term potentiation (LTP) and long-term depression (LTD) are generally assumed to be cellular correlates for learning and memory. Different types of LTP induction protocols differing in severity of stimulation can be distinguished in CA1 of the hippocampus. To better understand signaling mechanisms and involvement of neuromodulators such as dopamine (DA) in synaptic plasticity, less severe and more physiological low frequency induction protocols should be used. In the study which is reviewed here, critical determinants of spike timing-dependent plasticity (STDP) at hippocampal CA3-CA1 synapses were investigated. We found that DA via D1 receptor signaling, but not adrenergic signaling activated by the β-adrenergic agonist isoproterenol, is important for successful expression of STDP at CA3-CA1 synapses. The DA effect on STDP is paralleled by changes in spike firing properties, thereby changing intrinsic excitability of postsynaptic CA1 neurons, and gating STDP. Whereas β-adrenergic signaling also leads to a similar (but not identical) regulation of firing pattern, it does not enable STDP. In this focused review we will discuss the current literature on dopaminergic modulation of LTP in CA1, with a special focus on timing dependent (t-)LTP, and we will suggest possible reasons for the selective gating of STDP by DA [but not noradrenaline (NA)] in CA1.

  11. IKCa channels are a critical determinant of the slow AHP in CA1 pyramidal neurons.

    Science.gov (United States)

    King, Brian; Rizwan, Arsalan P; Asmara, Hadhimulya; Heath, Norman C; Engbers, Jordan D T; Dykstra, Steven; Bartoletti, Theodore M; Hameed, Shahid; Zamponi, Gerald W; Turner, Ray W

    2015-04-14

    Control over the frequency and pattern of neuronal spike discharge depends on Ca2+-gated K+ channels that reduce cell excitability by hyperpolarizing the membrane potential. The Ca2+-dependent slow afterhyperpolarization (sAHP) is one of the most prominent inhibitory responses in the brain, with sAHP amplitude linked to a host of circuit and behavioral functions, yet the channel that underlies the sAHP has defied identification for decades. Here, we show that intermediate-conductance Ca2+-dependent K+ (IKCa) channels underlie the sAHP generated by trains of synaptic input or postsynaptic stimuli in CA1 hippocampal pyramidal cells. These findings are significant in providing a molecular identity for the sAHP of central neurons that will identify pharmacological tools capable of potentially modifying the several behavioral or disease states associated with the sAHP.

  12. OLM interneurons differentially modulate CA3 and entorhinal inputs to hippocampal CA1 neurons.

    Science.gov (United States)

    Leão, Richardson N; Mikulovic, Sanja; Leão, Katarina E; Munguba, Hermany; Gezelius, Henrik; Enjin, Anders; Patra, Kalicharan; Eriksson, Anders; Loew, Leslie M; Tort, Adriano B L; Kullander, Klas

    2012-11-01

    The vast diversity of GABAergic interneurons is believed to endow hippocampal microcircuits with the required flexibility for memory encoding and retrieval. However, dissection of the functional roles of defined interneuron types has been hampered by the lack of cell-specific tools. We identified a precise molecular marker for a population of hippocampal GABAergic interneurons known as oriens lacunosum-moleculare (OLM) cells. By combining transgenic mice and optogenetic tools, we found that OLM cells are important for gating the information flow in CA1, facilitating the transmission of intrahippocampal information (from CA3) while reducing the influence of extrahippocampal inputs (from the entorhinal cortex). Furthermore, we found that OLM cells were interconnected by gap junctions, received direct cholinergic inputs from subcortical afferents and accounted for the effect of nicotine on synaptic plasticity of the Schaffer collateral pathway. Our results suggest that acetylcholine acting through OLM cells can control the mnemonic processes executed by the hippocampus.

  13. Phorbol esters broaden the action potential in CA1 hippocampal pyramidal cells.

    Science.gov (United States)

    Storm, J F

    1987-03-20

    Intracellular recordings were made from CA1 pyramidal cells in rat hippocampal slices. Single action potentials were elicited by injection of brief current pulses. Bath application of phorbol esters (4 beta-phorbol-12,13-diacetate, 0.3-5 microM; or 4 beta-phorbol-12,13-dibutyrate, 5-10 microM) broadened the action potential in each of the cells tested (n = 9). The broadening reflected slowing of the repolarization, whereas the upstroke of the spike was unchanged. This effect may enhance transmitter release from synaptic terminals, and contribute to enhancement of synaptic transmission through activation of protein kinase C, a mechanism which has been associated with long term potentiation.

  14. Ultrastructural abnormalities in CA1 hippocampus caused by deletion of the actin regulator WAVE-1.

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    Diána Hazai

    Full Text Available By conveying signals from the small GTPase family of proteins to the Arp2/3 complex, proteins of the WAVE family facilitate actin remodeling. The WAVE-1 isoform is expressed at high levels in brain, where it plays a role in normal synaptic processing, and is implicated in hippocampus-dependent memory retention. We used electron microscopy to determine whether synaptic structure is modified in the hippocampus of WAVE-1 knockout mice, focusing on the neuropil of CA1 stratum radiatum. Mice lacking WAVE-1 exhibited alterations in the morphology of both axon terminals and dendritic spines; the relationship between the synaptic partners was also modified. The abnormal synaptic morphology we observed suggests that signaling through WAVE-1 plays a critical role in establishing normal synaptic architecture in the rodent hippocampus.

  15. Li2Ca1.5Nb3O10 from X-ray powder data

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    Bai-Chuan Zhu

    2011-04-01

    Full Text Available Lithium calcium niobium oxide (2/1.5/3/10, Li2Ca1.5Nb3O10, has been synthesized by conventional solid-state reaction. Its structure consists of triple-layer perovskite slabs of corner-sharing NbO6 octahedra interleaved with lithium ions; Ca cations partially occupy the perovskite A sites at 75% occupancy probability. All eight atoms in the asymmetric unit are on special positions: one Nb atom has site symmetry 4/mmm; the second Nb, both K, the Sr and two O atoms have site symmetry 4mm; the remaining two O atoms have site symmetries 2mm. and mmm., respectively.

  16. Structured Dendritic Inhibition Supports Branch-Selective Integration in CA1 Pyramidal Cells.

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    Bloss, Erik B; Cembrowski, Mark S; Karsh, Bill; Colonell, Jennifer; Fetter, Richard D; Spruston, Nelson

    2016-03-02

    Neuronal circuit function is governed by precise patterns of connectivity between specialized groups of neurons. The diversity of GABAergic interneurons is a hallmark of cortical circuits, yet little is known about their targeting to individual postsynaptic dendrites. We examined synaptic connectivity between molecularly defined inhibitory interneurons and CA1 pyramidal cell dendrites using correlative light-electron microscopy and large-volume array tomography. We show that interneurons can be highly selective in their connectivity to specific dendritic branch types and, furthermore, exhibit precisely targeted connectivity to the origin or end of individual branches. Computational simulations indicate that the observed subcellular targeting enables control over the nonlinear integration of synaptic input or the initiation and backpropagation of action potentials in a branch-selective manner. Our results demonstrate that connectivity between interneurons and pyramidal cell dendrites is more precise and spatially segregated than previously appreciated, which may be a critical determinant of how inhibition shapes dendritic computation.

  17. Increased vulnerability of hippocampal CA1 neurons to hypoperfusion in ataxia and male sterility (AMS) mouse.

    Science.gov (United States)

    Liang, Xueyun; Nagai, Atsushi; Sheikh, Abdullah Md; Wang, Hui; Mitaki, Shingo; Araki, Asuka; Maruyama, Riruke; Harada, Takayuki

    2013-02-04

    The nna1 gene mutation is associated with spontaneous degeneration of cerebellar Purkinje cells and germ cells in Ataxia and Male Sterility (AMS) mouse. Since nna1 is also expressed in hippocampal neurons, we investigated their vulnerability to hypoperfusion in AMS mouse. Eight-week-old male wild type (WT) and AMS mice were subjected to bilateral common carotid artery occlusion (BCCAO) for 10 min and sacrificed 1, 3, 7 and 28 days after BCCAO. Nissl staining revealed the neuronal cell loss and pyknotic change in the CA1 of AMS mice. TUNEL(+) apoptotic cells were found in the area at 7 days in AMS mice. Bcl-2 mRNA and protein in WT hippocampus were increased, while they were not increased in AMS. Bax mRNA was increased in AMS. Moreover, Bax activation was immunohistochemically demonstrated only in AMS at 3 and 7 days after BCCAO. An oxidative DNA damage marker, 8-hydroxydeoxyguanosine-positive cells were increased in both strains at 1 day; decreased in WT at 3 days but remained high in AMS. BCCAO increased glutathione, an antioxidant, in WT, but not in AMS at 3 days. The mRNA level of mitochondrial uncoupling protein 2, a regulator of oxidative stress, was increased only in WT at 1 day. Nna1 mRNA was similarly expressed in WT and AMS, but the protein was undetectable in AMS. Thus, our results indicate the increased vulnerability of hippocampal CA1 neurons of AMS mice to cerebral hypoperfusion could be due to an imbalance between oxidative stress and antioxidative defense system.

  18. Hippocampal CA1 transcriptional profile of sleep deprivation: relation to aging and stress.

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    Nada M Porter

    Full Text Available BACKGROUND: Many aging changes seem similar to those elicited by sleep-deprivation and psychosocial stress. Further, sleep architecture changes with age suggest an age-related loss of sleep. Here, we hypothesized that sleep deprivation in young subjects would elicit both stress and aging-like transcriptional responses. METHODOLOGY/PRINCIPAL FINDINGS: F344 rats were divided into control and sleep deprivation groups. Body weight, adrenal weight, corticosterone level and hippocampal CA1 transcriptional profiles were measured. A second group of animals was exposed to novel environment stress (NES, and their hippocampal transcriptional profiles measured. A third cohort exposed to control or SD was used to validate transcriptional results with Western blots. Microarray results were statistically contrasted with prior transcriptional studies. Microarray results pointed to sleep pressure signaling and macromolecular synthesis disruptions in the hippocampal CA1 region. Animals exposed to NES recapitulated nearly one third of the SD transcriptional profile. However, the SD-aging relationship was more complex. Compared to aging, SD profiles influenced a significant subset of genes. mRNA associated with neurogenesis and energy pathways showed agreement between aging and SD, while immune, glial, and macromolecular synthesis pathways showed SD profiles that opposed those seen in aging. CONCLUSIONS/SIGNIFICANCE: We conclude that although NES and SD exert similar transcriptional changes, selective presynaptic release machinery and Homer1 expression changes are seen in SD. Among other changes, the marked decrease in Homer1 expression with age may represent an important divergence between young and aged brain response to SD. Based on this, it seems reasonable to conclude that therapeutic strategies designed to promote sleep in young subjects may have off-target effects in the aged. Finally, this work identifies presynaptic vesicular release and intercellular

  19. Computational modeling reveals dendritic origins of GABA(A-mediated excitation in CA1 pyramidal neurons.

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    Naomi Lewin

    Full Text Available GABA is the key inhibitory neurotransmitter in the adult central nervous system, but in some circumstances can lead to a paradoxical excitation that has been causally implicated in diverse pathologies from endocrine stress responses to diseases of excitability including neuropathic pain and temporal lobe epilepsy. We undertook a computational modeling approach to determine plausible ionic mechanisms of GABA(A-dependent excitation in isolated post-synaptic CA1 hippocampal neurons because it may constitute a trigger for pathological synchronous epileptiform discharge. In particular, the interplay intracellular chloride accumulation via the GABA(A receptor and extracellular potassium accumulation via the K/Cl co-transporter KCC2 in promoting GABA(A-mediated excitation is complex. Experimentally it is difficult to determine the ionic mechanisms of depolarizing current since potassium transients are challenging to isolate pharmacologically and much GABA signaling occurs in small, difficult to measure, dendritic compartments. To address this problem and determine plausible ionic mechanisms of GABA(A-mediated excitation, we built a detailed biophysically realistic model of the CA1 pyramidal neuron that includes processes critical for ion homeostasis. Our results suggest that in dendritic compartments, but not in the somatic compartments, chloride buildup is sufficient to cause dramatic depolarization of the GABA(A reversal potential and dominating bicarbonate currents that provide a substantial current source to drive whole-cell depolarization. The model simulations predict that extracellular K(+ transients can augment GABA(A-mediated excitation, but not cause it. Our model also suggests the potential for GABA(A-mediated excitation to promote network synchrony depending on interneuron synapse location - excitatory positive-feedback can occur when interneurons synapse onto distal dendritic compartments, while interneurons projecting to the perisomatic

  20. [Research on Optical Parameter along Puncture Path in Spinal Surgery Navigation Based on Near Infrared Spectroscopy].

    Science.gov (United States)

    Wang, Yuyan; Qian, Zhiyu; Li, Weitao; Liu, Yangyang; Xie, Jieru

    2015-06-01

    Accurate placement of pedicle screws is a key factor of spinal surgery. Investigation of a new real-time intra-operative monitoring method is an important area of clinical application research which makes a contribution to planting pedicle screw accurately. Porcine spines were chosen as experimental objects. The changes of reduced scattering coefficient (μ'(s)) along normal puncture path, medial perforation path and lateral perforation path were measured and studied. A conclusion is drawn that there are two distinct peaks throughout the puncture process, appearing at the junction of cancellous bone and cortical bone, at the beginning and at the end, respectively. The reduced scattering coefficient is proved to be a good monitoring factor which can identify whether the screw is about to reach the critical position of the spine puncture. Moreover, the variation provides an important reference for spinal surgical navigation process.

  1. IMMUNOHISTOCHEMICAL STUDY ON CHANGE OF 5-HT IN CA1 SECTOR OF HIPPOCAMPUS FOLLOWING CEREBRAL ISCHEMIA%脑缺血海马CA1区5-HT变化的免疫组织化学研究

    Institute of Scientific and Technical Information of China (English)

    郭泽云; 吴春云; 李素华; 李玲; 陈植和

    2000-01-01

    Objective: To observe the change of 5-HT in CA1 sector of hippocampus in gerbils followingcerebral ischemia and reperfusion for discussing the relationship between the damage of neuronsin CA1 sector and the change of 5-HT after cerebral ischemia. Methods: The change of 5-HT inCA1 sector of hippocampus in gerbils following cerebral ischemia and reperfusion was examinedby ABC method of immunohistochemistry and image analysis technique. Results: (1) The meanvalue of optic density (OD) of 5-HT immunoreaction fiber in CA1 sector had no significant difference between the 10 min ischemic treated group and control group, whereas the OD of 5-HT wasdecreased significantly in 30 min and 4 h ischemia treated group. (2) The OD of 5-HT immunoreaction fiber in CA1 was decreased in 10 min cerebral ischemia following 30 min and 4 h reperfusion and was the lowest after 24 h reperfusion. After 36 h reperfusion, the OD became normalgradually. Conclusion: The content of 5-HT in CA1 sector of hippocampus is decreased in cerebral ischemia and reperfusion. The change of 5-HT may be involved in neuron damage of CA1 incerebral ischemia and reperfusion.%目的:观察脑缺血及缺血再灌流海马CA1区5-HT的变化,探讨脑缺血海马CA1区神经元损伤与5-HT变化的关系。方法:用免疫组织化学ABC法及图像分析技术对沙土鼠脑缺血海马CA1区5-HT含量变化进行研究。结果:(1)脑缺血10 min时,沙土鼠海马CA1区5-HT免疫反应阳性纤维的平均光密度值(OD)与对照组比较无显著性差异,而缺血30 min时,OD值则下降,4 h时下降得更多,P<0.05。(2)脑缺血10 min再灌流30 min时5-HT的OD值即降低,再灌流4 h时进一步降低,再灌流24 h时最低,P<0.05,至36 h时OD值逐渐恢复正常。结论:沙土鼠海马CA1区5-HT含量在脑缺血及缺血再灌流时均降低,提示海马CA1区神经元缺血损伤可能与5-HT的紊乱有关。

  2. Intrathoracic caecal perforation presenting as dyspnea.

    Science.gov (United States)

    Granier, Vincent; Coche, Emmanuel; Hantson, Philippe; Thoma, Maximilien

    2010-01-01

    Introduction. Bochdalek hernia is a congenital defect of the diaphragm that is usually diagnosed in the neonatal period and incidentally in asymptomatic adults. Small bowel incarceration in a right-sided Bochdalek hernia is exceptional for an adult. Case Presentation. A 54-year-old woman was admitted for acute dyspnea, tachycardia, hypotension, and fever. Five days before, she had been experiencing an episode of diffuse abdominal pain. The admission chest X-ray was interpreted as right pleural effusion and pneumothorax with left mediastinal shift. Chest tube drainage was purulent. The thoracoabdominal CT examination suspected an intestinal incarceration through a right diaphragmatic defect. At laparotomy, a right-sided Bochdalek hernia was confirmed with a complete necrosis of the incarcerated caecum. Ileocaecal resection was performed, but the patient died from delayed septic complications. Conclusion. Intrathoracic perforation of the caecum is a rare occurrence; delayed diagnosis due to misleading initial symptoms may lead to severe complications and poor prognosis.

  3. Spontaneous Perforation of Pyometra: A Case Report

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Pyometra is the accumulation of purulent material in the uterine cavity. Its reported incidence is 0.01–0.5% in gynecologic patients; however, as far as elderly patients are concerned, its incidence is 13.6% [3]. The most common cause of pyometra is malignant diseases of genital tract and the consequences of their treatment (radiotherapy. Other causes are benign tumors like leiomyoma, endometrial polyps, senile cervicitis, cervical occlusion after surgery, puerperal infections, and congenital cervical anomalies. Spontaneous rupture of the uterus is an extremely rare complication of pyometra. To our knowledge, only 21 cases of spontaneous perforation of pyometra have been reported in English literature since 1980. This paper reports an additional case of spontaneous uterine rupture.

  4. Intrathoracic Caecal Perforation Presenting as Dyspnea

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    Vincent Granier

    2010-01-01

    Full Text Available Introduction. Bochdalek hernia is a congenital defect of the diaphragm that is usually diagnosed in the neonatal period and incidentally in asymptomatic adults. Small bowel incarceration in a right-sided Bochdalek hernia is exceptional for an adult. Case Presentation. A 54-year-old woman was admitted for acute dyspnea, tachycardia, hypotension, and fever. Five days before, she had been experiencing an episode of diffuse abdominal pain. The admission chest X-ray was interpreted as right pleural effusion and pneumothorax with left mediastinal shift. Chest tube drainage was purulent. The thoracoabdominal CT examination suspected an intestinal incarceration through a right diaphragmatic defect. At laparotomy, a right-sided Bochdalek hernia was confirmed with a complete necrosis of the incarcerated caecum. Ileocaecal resection was performed, but the patient died from delayed septic complications. Conclusion. Intrathoracic perforation of the caecum is a rare occurrence; delayed diagnosis due to misleading initial symptoms may lead to severe complications and poor prognosis.

  5. Detection of Perforators Using Smartphone Thermal Imaging.

    Science.gov (United States)

    Hardwicke, Joseph T; Osmani, Omer; Skillman, Joanna M

    2016-01-01

    Thermal imaging detects infrared radiation from an object, producing a thermogram that can be interpreted as a surrogate marker for cutaneous blood flow. To date, high-resolution cameras typically cost tens of thousands of dollars. The FLIR ONE is a smartphone-compatible miniature thermal imaging camera that currently retails at under $200. In a proof-of-concept study, patients and healthy volunteers were assessed with thermal imaging for (1) detecting and mapping perforators, (2) defining perforasomes, and (3) monitoring free flaps. Preoperative, intraoperative, and postoperative thermograms can assist in the planning, execution, and monitoring of free flaps, and the FLIR ONE provides a low-cost adjunct that could be applied to other areas of burns and plastic surgery.

  6. Preliminary Clinical Study on Perforating Prosthokeratoplasty

    Institute of Scientific and Technical Information of China (English)

    Jian Chen; Jintang Xu; SA Yakimenko; Guanghui Hou; Bingji Sun; Aning Zheng; Songbin Zhao

    2003-01-01

    Purpose: To observe the effects of perforating prosthokeratoplasty on patients with leucoma who failed in keratoplasty or were not suitable for keratoplasty, and improved their vision.Methods:Five cases with leucoma (4 with chemical burn and 1 with blast) received Yakimenko Style keratoprosthesis implantation. Preoperative examination showed the visual acuity in 4 of the 5 cases was light perception, and that of the other one was FC/20 crm.The light orientation in 3 patients was definite, and that in the other two was indefinite.Results: The vision improved in 4 of 5 patients in the follow-up period of 9 months to 3 years. Their visual acuity showed 0.09 to 0.8. And there was no change of vision in the other 1 case.Conclutions :Prosthokeratoplasty is the first choice for rehabilitation of the blind that have leucoma but are not suitable for or failed in penetrating keratoplasty.

  7. Medical image of the week: tracheal perforation

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    Parsa N

    2014-12-01

    Full Text Available A 45 year old Caucasian man with a history of HIV/AIDS was admitted for septic shock secondary to right lower lobe community acquired pneumonia. The patient’s respiratory status continued to decline requiring emergency intubation in a non-ICU setting. Four laryngoscope intubation attempts were made including an inadvertent esophageal intubation. Subsequent CT imaging revealed a tracheal defect (Figure 1, red arrow with communication to the mediastinum and air around the trachea consistent with pneumomediastinum (Figure 2, orange arrow and figure 3, yellow arrow. Pneumopericardium (figure 4, blue arrow was also evident post-intubation. The patient’s hemodynamic status remained stable. Two days following respiratory intubation subsequent chest imaging revealed resolution of the pneumomediastinum and pneumopericardium and patient continued to do well without hemodynamic compromise or presence of subcutaneous emphysema. Post-intubation tracheal perforation is a rare complication of traumatic intubation and may be managed with surgical intervention or conservative treatment (1.

  8. Clinical nursing path after endoscopic submucosal dissection reduces the risk of postoperative complications

    Institute of Scientific and Technical Information of China (English)

    Xia Bai; Jun-Ping Wang; Lan Ming; Ya-Jie Xu; Xia Sun

    2016-01-01

    Objective: To investigate the effect of the nursing path on postoperative complications after endoscopic submucosal dissection (ESD). Method: Patients' nursing paths for ESD were established based on a systematic analysis of relevant literature, previous clinical procedures and consultation with chief physicians from a gastroenterology department. Forty patients were divided into the observation or control group and were assigned to follow the nursing path or the conventional path after an ESD, respectively. Next, the incidence of postoperative complications of these two groups was measured, primarily assessing the occurrences of bleeding, perforation, infection, and anxiety. Results: The incidence of complications after ESD in the observation group was remarkably lower than that of the control group (P Conclusion: The nursing path for ESD has a positive role in reducing certain frequent complications that occur after ESD, particularly infection and anxiety;in addition, the nursing path optimizes nursing care in patients with gastrointestinal stromal tumor.

  9. Influence of operating microscope in the sealing of cervical perforations

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    Bruna Schwingel Schmidt

    2016-01-01

    Full Text Available Context: Accidental root canal perforations are among the main complications of endodontic treatment. Aim: This study evaluated the influence of operating microscope (OM in the marginal adaptation of mineral trioxide aggregate (MTA (Angelus® and glass ionomer (Vitremer inserted into cervical perforations. Materials and Methods: Perforations were made in the cervical third of the buccal wall of the root canal in mandibular incisors. Next, the teeth were divided into four groups (N = 10: MG - MTA without OM; VG - Vitremer without OM; MOMG - MTA with OM; VOMG - Vitremer with OM. The perforations were sealed according to the group and the teeth were prepared for analysis by confocal laser scanning microscope. Images of perforation region (1,024Χ were made and the gap presented by the materials was measured using the Image J program. LEXT OLS4100 three dimensional (3D measuring laser microscope measured the volumetric misfit. Data of gap were analyzed by Kruskal-Wallis and Dunn′s tests. Analysis of variance (ANOVA and Tukey′s tests compared the volumetric misfits. Results: The results showed lower volume and gap in the interface dentin/material in VOMG compared to the other groups (P < 0.05. Conclusion: The use of OM improved the quality of cervical perforations sealed with Vitremer, being indicated in clinical situations of iatrogenic cervical perforations.

  10. Risk of surgical glove perforation in oral and maxillofacial surgery.

    Science.gov (United States)

    Kuroyanagi, N; Nagao, T; Sakuma, H; Miyachi, H; Ochiai, S; Kimura, Y; Fukano, H; Shimozato, K

    2012-08-01

    Oral and maxillofacial surgery, which involves several sharp instruments and fixation materials, is consistently at a high risk for cross-contamination due to perforated gloves, but it is unclear how often such perforations occur. This study aimed to address this issue. The frequency of the perforation of surgical gloves (n=1436) in 150 oral and maxillofacial surgeries including orthognathic surgery (n=45) was assessed by the hydroinsufflation technique. Orthognathic surgery had the highest perforation rate in at least 1 glove in 1 operation (91.1%), followed by cleft lip and palate surgery (55.0%), excision of oral soft tumour (54.5%) and dental implantation (50.0%). The perforation rate in scrub nurses was 63.4%, followed by 44.4% in surgeons and first assistants, and 16.3% in second assistants. The odds ratio for the perforation rate in orthognathic surgery versus other surgeries was 16.0 (95% confidence interval: 5.3-48.0). The protection rate offered by double gloving in orthognathic surgery was 95.2%. These results suggest that, regardless of the surgical duration and blood loss in all fields of surgery, orthognathic surgery must be categorized in the highest risk group for glove perforation, following gynaecological and open lung surgery, due to the involvement of sharp objects.

  11. Wave Run-up on A Coaxial Perforated Circular Cylinder

    Institute of Scientific and Technical Information of China (English)

    ZHU Da-tong

    2011-01-01

    This paper describes a plane regular wave interaction with a combined cylinder which consists of a solid inner column and a coaxial perforated outer cylinder. The outer perforated surface is a thin porous cylinder with an annular gap between it and the inner cylinder. The non-linear boundary condition at the perforated wall is a prime focus in the study;energy dissipation at the perforated wall occurs through the resistance to the fluid across the perforated wall. Explicit analytical formulae are presented to calculate the wave run-up on the outer and inner surfaces of the perforated cylinderand the surface of the inner column. The theoretical results of the wave run-up are compared with previous experimental data. Numerical results have also been obtained: when the ratio of the annular gap between the two cylinders to incidentwavelength (b-a)/L≤0.1, the wave run-up on the inner surface of the perforated cylinder and the surface of inner column can partially or completely exceed the incident wave height.

  12. Premixed Combustion of Coconut Oil on Perforated Burner

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    I.K.G. Wirawan

    2013-10-01

    Full Text Available Coconut oil premixed combustion behavior has been studied experimentally on perforated burner with equivalence ratio (φ varied from very lean until very rich. The results showed that burning of glycerol needs large number of air so that the laminar burning velocity (SL is the highest at very lean mixture and the flame is in the form of individual Bunsen flame on each of the perforated plate hole. As φ is increased the  SL decreases and the secondary Bunsen flame with open tip occurs from φ =0.54 at the downstream of perforated flame. The perforated flame disappears at φ = 0.66 while the secondary Bunsen flame still exist with SL increases following that of hexadecane flame trend and then extinct when the equivalence ratio reaches one or more. Surrounding ambient air intervention makes SL decreases, shifts lower flammability limit into richer mixture, and performs triple and cellular flames. The glycerol diffusion flame radiation burned fatty acids that perform cellular islands on perforated hole.  Without glycerol, laminar flame velocity becomes higher and more stable as perforated flame at higher φ. At rich mixture the Bunsen flame becomes unstable and performs petal cellular around the cone flame front. Keywords: cellular flame; glycerol; perforated flame;secondary Bunsen flame with open tip; triple flame

  13. A computational study on plasticity during theta cycles at Schaffer collateral synapses on CA1 pyramidal cells in the hippocampus.

    Science.gov (United States)

    Saudargiene, Ausra; Cobb, Stuart; Graham, Bruce P

    2015-02-01

    Cellular activity in the CA1 area of the hippocampus waxes and wanes at theta frequency (4-8 Hz) during exploratory behavior of rats. Perisomatic inhibition onto pyramidal cells tends to be strongest out of phase with pyramidal cell activity, whereas dendritic inhibition is strongest in phase with pyramidal cell activity. Synaptic plasticity also varies across the theta cycle, from strong long-term potentiation (LTP) to long-term depression (LTD), putatively corresponding to encoding and retrieval phases for information patterns encoded by pyramidal cell activity (Hasselmo et al. (2002a) Neural Comput 14:793-817). The mechanisms underpinning the phasic changes in plasticity are not clear, but it is likely that inhibition plays a role by affecting levels of electrical activity and calcium concentration at synapses. We explore the properties of synaptic plasticity during theta at Schaffer collateral synapses on CA1 pyramidal neurons and the influence of spatially and temporally targeted inhibition using a detailed multicompartmental model of the CA1 pyramidal neuron microcircuit and a phenomenological model of synaptic plasticity. The results suggest CA3-CA1 synapses are potentiated on one phase of theta due to high calcium levels provided by paired weak CA3 and layer III entorhinal cortex (EC) inputs even when somatic spiking is inhibited by perisomatic interneuron activity. Weak CA3 inputs alone induce lower calcium transients and result in depression of the CA3-CA1 synapses. These synapses are depressed if activated in phase with dendritic inhibition as strong CA3 inputs alone are not able to cause high calcium in this theta phase even though the CA1 pyramidal neuron shows somatic spiking. Dendritic inhibition acts as a switch that prevents LTP and promotes LTD during the retrieval phases of the theta rhythm in CA1 pyramidal cell. This may be important for not overly reinforcing recalled memories and in forgetting no longer relevant memories.

  14. Action potential modulation in CA1 pyramidal neuron axons facilitates OLM interneuron activation in recurrent inhibitory microcircuits of rat hippocampus.

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    Sooyun Kim

    Full Text Available Oriens-lacunosum moleculare (O-LM interneurons in the CA1 region of the hippocampus play a key role in feedback inhibition and in the control of network activity. However, how these cells are efficiently activated in the network remains unclear. To address this question, I performed recordings from CA1 pyramidal neuron axons, the presynaptic fibers that provide feedback innervation of these interneurons. Two forms of axonal action potential (AP modulation were identified. First, repetitive stimulation resulted in activity-dependent AP broadening. Broadening showed fast onset, with marked changes in AP shape following a single AP. Second, tonic depolarization in CA1 pyramidal neuron somata induced AP broadening in the axon, and depolarization-induced broadening summated with activity-dependent broadening. Outside-out patch recordings from CA1 pyramidal neuron axons revealed a high density of α-dendrotoxin (α-DTX-sensitive, inactivating K+ channels, suggesting that K+ channel inactivation mechanistically contributes to AP broadening. To examine the functional consequences of axonal AP modulation for synaptic transmission, I performed paired recordings between synaptically connected CA1 pyramidal neurons and O-LM interneurons. CA1 pyramidal neuron-O-LM interneuron excitatory postsynaptic currents (EPSCs showed facilitation during both repetitive stimulation and tonic depolarization of the presynaptic neuron. Both effects were mimicked and occluded by α-DTX, suggesting that they were mediated by K+ channel inactivation. Therefore, axonal AP modulation can greatly facilitate the activation of O-LM interneurons. In conclusion, modulation of AP shape in CA1 pyramidal neuron axons substantially enhances the efficacy of principal neuron-interneuron synapses, promoting the activation of O-LM interneurons in recurrent inhibitory microcircuits.

  15. Action potential modulation in CA1 pyramidal neuron axons facilitates OLM interneuron activation in recurrent inhibitory microcircuits of rat hippocampus.

    Science.gov (United States)

    Kim, Sooyun

    2014-01-01

    Oriens-lacunosum moleculare (O-LM) interneurons in the CA1 region of the hippocampus play a key role in feedback inhibition and in the control of network activity. However, how these cells are efficiently activated in the network remains unclear. To address this question, I performed recordings from CA1 pyramidal neuron axons, the presynaptic fibers that provide feedback innervation of these interneurons. Two forms of axonal action potential (AP) modulation were identified. First, repetitive stimulation resulted in activity-dependent AP broadening. Broadening showed fast onset, with marked changes in AP shape following a single AP. Second, tonic depolarization in CA1 pyramidal neuron somata induced AP broadening in the axon, and depolarization-induced broadening summated with activity-dependent broadening. Outside-out patch recordings from CA1 pyramidal neuron axons revealed a high density of α-dendrotoxin (α-DTX)-sensitive, inactivating K+ channels, suggesting that K+ channel inactivation mechanistically contributes to AP broadening. To examine the functional consequences of axonal AP modulation for synaptic transmission, I performed paired recordings between synaptically connected CA1 pyramidal neurons and O-LM interneurons. CA1 pyramidal neuron-O-LM interneuron excitatory postsynaptic currents (EPSCs) showed facilitation during both repetitive stimulation and tonic depolarization of the presynaptic neuron. Both effects were mimicked and occluded by α-DTX, suggesting that they were mediated by K+ channel inactivation. Therefore, axonal AP modulation can greatly facilitate the activation of O-LM interneurons. In conclusion, modulation of AP shape in CA1 pyramidal neuron axons substantially enhances the efficacy of principal neuron-interneuron synapses, promoting the activation of O-LM interneurons in recurrent inhibitory microcircuits.

  16. Laser-mediated perforation of plant cells

    Science.gov (United States)

    Wehner, Martin; Jacobs, Philipp; Esser, Dominik; Schinkel, Helga; Schillberg, Stefan

    2007-07-01

    The functional analysis of plant cells at the cellular and subcellular levels requires novel technologies for the directed manipulation of individual cells. Lasers are increasingly exploited for the manipulation of plant cells, enabling the study of biological processes on a subcellular scale including transformation to generate genetically modified plants. In our setup either a picosecond laser operating at 1064 nm wavelength or a continuous wave laser diode emitting at 405 nm are coupled into an inverse microscope. The beams are focused to a spot size of about 1.5 μm and the tobacco cell protoplasts are irradiated. Optoporation is achieved when targeting the laser focal spot at the outermost edge of the plasma membrane. In case of the picosecond laser a single pulse with energy of about 0.4 μJ was sufficient to perforate the plasma membrane enabling the uptake of dye or DNA from the surrounding medium into the cytosol. When the ultraviolet laser diode at a power level of 17 mW is employed an irradiation time of 200 - 500 milliseconds is necessary to enable the uptake of macromolecules. In the presence of an EYFP encoding plasmid with a C-terminal peroxisomal signal sequence in the surrounding medium transient transformation of tobacco protoplasts could be achieved in up to 2% of the optoporated cells. Single cell perforation using this novel optoporation method shows that isolated plant cells can be permeabilized without direct manipulation. This is a valuable procedure for cell-specific applications, particularly where the import of specific molecules into plant cells is required for functional analysis.

  17. Esophageal Perforation with Unilateral Fluidothorax Caused by Nasogastric Tube

    Directory of Open Access Journals (Sweden)

    Lukas P. Mileder

    2016-01-01

    Full Text Available Preterm infants are highly susceptible to injuries following necessary and often life-saving medical interventions. Esophageal perforation is a rare, yet serious complication that can be caused by aerodigestive tract suction, endotracheal intubation, or nasogastric tube placement. We present the case of a neonate born at 23 weeks plus three days of gestation with chest radiography showing malposition of the nasogastric feeding tube and massive right-sided effusion of Iopamidol in the pleural cavity due to esophageal perforation. In addition, the article summarizes common signs and symptoms associated with esophageal perforation in infants and discusses diagnostic approaches.

  18. Successful management of late right ventricular perforation after pacemaker implantation

    Directory of Open Access Journals (Sweden)

    Amir K Bigdeli

    2010-01-01

    Full Text Available Amir K Bigdeli1, Andres Beiras-Fernandez1, Ingo Kaczmarek1, Christian Kowalski2, Michael Schmoeckel1, Bruno Reichart11Department of Cardiac Surgery, 2Department of Anesthesiology, Ludwig-Maximilians University, Munich, GermanyAbstract: Complications of pacemaker implantation include myocardial perforation, venous thrombosis, vegetations of the tricuspid valve or pacing lead, and tricuspid regurgitation. We report a patient presenting with a case of delayed ventricular lead perforation through the right ventricle. The lead was uneventfully extracted under transesophageal echocardiographic observation in the operating room with cardiac surgery backup.Keywords: pacemaker, lead perforation, complication

  19. Oral antibiotics for perforated appendicitis is not recommended

    DEFF Research Database (Denmark)

    Gögenur, Ismail; Rosenberg, Jacob; Alamili, Mahdi

    2010-01-01

    In the majority of surgical departments in Denmark, the postoperative treatment for acute perforated appendicitis comprises three days of intravenous antibiotics. Recently, it has been proposed that such antibiotic regimen should be replaced by orally administered antibiotics. The aim of this paper...... was to give an overview of studies on acute perforated appendicitis with postoperative oral antibiotics. Five studies were found in a database search covering the 1966-2009 period. There is no evidence to support a conversion of the postoperative antibiotic regimen from intravenous to oral administration...... in patients with acute perforated appendicitis....

  20. A Rare Acute Abdomen Reason: Perforated Jejunal Diverticulitis

    Directory of Open Access Journals (Sweden)

    Oktay Karakose

    2014-06-01

    Full Text Available Jejunal diverticulosis is a rare case that is diagnosed incidental. Although it is generally asymptomatic, it can cause non-spesific symptoms like stomachache, nausea, diarrhoea, malabsorption, bleeding, obstruction and / or perforation. Perforated jejunal diverticulitis is a very rare acute abdomen cause. The acute complications of jejunal diverticulosis can be cause of significant morbidity and mortality especially in old patients. In this text, we report a 81 year old woman case that was operated emergently because of perforated jejunal diverticulitis and was lost in postoperation term because of multiple organ failure.

  1. Biliary peritonitis due to gall bladder perforation after percutaneous nephrolithotomy

    Directory of Open Access Journals (Sweden)

    Nikhil Ranjan

    2015-01-01

    Full Text Available A 19-year-old male patient underwent right percutaneous nephrolithotomy (PNL for right renal 1.5 × 1.5 cm lower pole stone. The procedure was completed uneventfully with complete stone clearance. The patient developed peritonitis and shock 48 h after the procedure. Exploratory laparotomy revealed a large amount of bile in the abdomen along with three small perforations in the gall bladder (GB and one perforation in the caudate lobe of the liver. Retrograde cholecystectomy was performed but the patient did not recover and expired post-operatively. This case exemplifies the high mortality of GB perforation after PNL and the lack of early clinical signs.

  2. Biliary peritonitis due to gall bladder perforation after percutaneous nephrolithotomy.

    Science.gov (United States)

    Ranjan, Nikhil; Singh, Rana Pratap; Tiwary, Rajesh

    2015-01-01

    A 19-year-old male patient underwent right percutaneous nephrolithotomy (PNL) for right renal 1.5 × 1.5 cm lower pole stone. The procedure was completed uneventfully with complete stone clearance. The patient developed peritonitis and shock 48 h after the procedure. Exploratory laparotomy revealed a large amount of bile in the abdomen along with three small perforations in the gall bladder (GB) and one perforation in the caudate lobe of the liver. Retrograde cholecystectomy was performed but the patient did not recover and expired post-operatively. This case exemplifies the high mortality of GB perforation after PNL and the lack of early clinical signs.

  3. Sen perforation af tyndtarm efter laparoskopisk gastrisk bypass

    DEFF Research Database (Denmark)

    Spanager, Lene; Sigild, Ulf Henrik; Neuenschwander, Anders Ulrich

    2010-01-01

    We present two cases in which the patients were admitted to a local hospital with acute abdominal pain four or five months after having undergone laparoscopic gastric bypass. In both cases, operation revealed a perforation of the small bowel close to the distal anastomosis. In the first case......, a massive constipation of the small bowel was most likely a contributing factor. In the second case, the cause was a kink of the entero-entero anastomosis leading to obstruction and finally perforation of the biliary limp. Late perforations are among the rarely reported complications associated with gastric...

  4. Phase transition in a tetragonal In sub 9 sub 0 Pb sub 1 sub 0 alloy under high pressure: a switch from c/a > 1 to c/a < 1

    CERN Document Server

    Degtyareva, V F; Porsch, F; Novokhatskaya, N I

    2003-01-01

    The effect of pressure on tetragonal In-Pb alloys with 10, 15, and 22 at.% Pb has been studied up to pressure 30 GPa with diamond anvil cells using synchrotron radiation. The In-type face-centred tetragonal phase of the In alloy with 10 at.% Pb undergoes under pressure a phase transition with a discontinuous jump of the axial ratio from c/a > 1 to c/a < 1 via a two-phase region from 7 to 20 GPa. The tetragonal phases of the In alloys with 15 and 22 at.% Pb with c/a < 1 at ambient pressure show only a slight decrease in c/a with pressure increase. The correlation of the axial ratio with the alloy content and its change with pressure in In alloys and In itself are attributed to Brillouin-zone-Fermi-sphere interactions.

  5. 吗啡依赖性大鼠海马CA1区NKB细胞的改变%The Alteration of NKB in CA1 of Hippocampus in Morphine Dependent Rats

    Institute of Scientific and Technical Information of China (English)

    周郦楠; 王冶; 张广新

    2004-01-01

    目的:观察吗啡依赖性大鼠海马CA1区NKB细胞的变化.方法:用皮下注射吗啡法建立雄性大鼠吗啡依赖模型.用免疫组织化学和图像分析方法观察大鼠CA1区NKB细胞的变化.结果:吗啡依赖性大鼠海马CA1区NKB细胞免疫反应减弱,与对照组相比差异显著(P<0.01).结论:NKB细胞减少与吗啡依赖性的发生、发展有关.

  6. External perforated Solar Screens for daylighting in residential desert buildings: Identification of minimum perforation percentages

    KAUST Repository

    Sherif, Ahmed

    2012-06-01

    The desert climate is endowed by clear sky conditions, providing an excellent opportunity for optimum utilization of natural light in daylighting building indoor spaces. However, the sunny conditions of the desert skies, in countries like Egypt and Saudi Arabia, result in the admittance of direct solar radiation, which leads to thermal discomfort and the incidence of undesired glare. One type of shading systems that is used to permit daylight while controlling solar penetration is " Solar Screens" Very little research work addressed different design aspects of external Solar Screens and their influence on daylighting performance, especially in desert conditions, although these screens proved their effectiveness in controlling solar radiation in traditional buildings throughout history.This paper reports on the outcomes of an investigation that studied the influence of perforation percentage of Solar Screens on daylighting performance in a typical residential living room of a building in a desert location. The objective was to identify minimum perforation percentage of screen openings that provides adequate illuminance levels in design-specific cases and all-year-round.Research work was divided into three stages. Stage one focused on the analysis of daylighting illuminance levels in specific dates and times, while the second stage was built on the results of the first stage, and addressed year round performance using Dynamic Daylight Performance Metrics (DDPMs). The third stage addressed the possibility of incidence of glare in specific cases where illuminance levels where found very high in some specific points during the analysis of first stage. The research examined the daylighting performance in an indoor space with a number of assumed fixed experimentation parameters that were chosen to represent the principal features of a typical residential living room located in a desert environment setting.Stage one experiments demonstrated that the screens fulfilled the

  7. External perforated window Solar Screens: The effect of screen depth and perforation ratio on energy performance in extreme desert environments

    KAUST Repository

    Sherif, A.

    2012-09-01

    In hot arid desert environments, the solar radiation passing through windows increases the cooling loads and the energy consumption of buildings. Shading of windows can reduce these loads. Unlike the woven solar screens, wooden solar screens have a thickness that provides selective shading properties. Perforated wooden solar screens were traditionally used for windows shading. Developing modern types of these shading systems can lead to significant energy savings. The paper addresses the influence of changing the perforation percentage and depth of these screens on the annual energy loads, hence defining the optimum depth/perforation configurations for various window orientations. Series of experiments were performed using the EnergyPlus simulation software for a typical residential building in the Kharga Oasis, located in the Egyptian desert. A range of perforation percentages and depths were tested. Conclusions prove that external fixed deep perforated solar screens could effectively achieve energy savings up to 30% of the total energy consumption in the West and South orientations. Optimum range of depths and perforation percentages were recommended. These are: 80-90% perforation rate and 1:1 depth/opening width ratio. These lighter and deeper solar screen configurations were found to be more efficient in energy consumption in comparison with the traditional ones. © 2012 Elsevier B.V. All rights reserved.

  8. Isoflurane depresses hippocampal CA1 glutamate nerve terminals without inhibiting fiber volleys

    Directory of Open Access Journals (Sweden)

    MacIver M Bruce

    2006-01-01

    Full Text Available Abstract Background Anesthetic-induced CNS depression is thought to involve reduction of glutamate release from nerve terminals. Recent studies suggest that isoflurane reduces glutamate release by block of Na channels. To further investigate this question we examined the actions of isoflurane, TTX, extracellular Ca2+, CNQX and stimulus voltage (stim on glutamate-mediated transmission at hippocampal excitatory synapses. EPSPs were recorded from CA1 neurons in rat hippocampal brain slices in response to Schaffer-collateral fiber stimulation. Results Isoflurane (350 μM; 1 MAC reversibly depressed EPSP amplitudes by ~60% while facilitation increased ~20%. Consistent with previous studies, these results indicate a presynaptic site of action that involves reduced excitation-release coupling. EPSPs were depressed to comparable levels by TTX (60 nM or lowered stim, but facilitation was not changed, indicating a simple failure of axonal conduction. Similarly, partial antagonism of postsynaptic glutamate receptors with CNQX (10 μM depressed EPSP amplitudes with no change in facilitation. However, EPSP depression by low external Ca2+ (0.8 mM was accompanied by an increase in facilitation comparable to isoflurane. Isoflurane depression of EPSP amplitudes could also be partly reversed by high external Ca2+ (4 mM that also decreased facilitation. Isoflurane or low Ca2+ markedly reduced the slopes of fiber volley (FV-EPSP input-output curves, consistent with little or no effect on FVs. By contrast, TTX didn't alter the FV-EPSP curve slope, indicating that EPSP depression resulted from FV depression. FVs were remarkably resistant to isoflurane. Somatic spike currents were unaffected by 350 μM (1 MAC isoflurane as well. The EC50 for isoflurane depression of FVs was ~2.8 mM (12 vol. %; 8 MAC. Conclusion Isoflurane appears to depress CA1 synapses at presynaptic sites downstream from Na channels, as evident by the increased facilitation that accompanies EPSP

  9. Hippocampal output area CA1 broadcasts a generalized novelty signal during an object-place recognition task.

    Science.gov (United States)

    Larkin, Margaret Carr; Lykken, Christine; Tye, Lynne D; Wickelgren, Jeanette Graham; Frank, Loren M

    2014-07-01

    Animals display an innate preference for novelty, spending more time exploring both novel objects and familiar objects in novel locations. This increase in exploration is thought to allow the animal to gather the information necessary to encode new experiences. Despite extensive evidence that increased exploration following spatial change requires the hippocampus, the pattern of hippocampal activity that supports this behavior remains unknown. We examined activity in hippocampal output area CA1 and one synapse upstream in area CA3 while freely behaving rats performed an object-place recognition task. We found that the presence of novelty substantially altered activity in CA1, but not in CA3. During exploration of displaced familiar objects and novel objects in unexpected locations, CA1 place cells showed robust increases in firing rate. These firing rate increases persisted during sharp wave ripples, when place cell representations of previous experiences are replayed. Unexpectedly, increases in CA1 activity were not spatially restricted to regions of the environment that underwent change, indicating a generalized novelty signal. We suggest that hippocampal area CA1 broadcasts the presence of novelty, rather than signaling what is novel, and simultaneously becomes more plastic, allowing the integration of new information into previously stored memories.

  10. Cell-Type-Specific Circuit Connectivity of Hippocampal CA1 Revealed through Cre-Dependent Rabies Tracing

    Directory of Open Access Journals (Sweden)

    Yanjun Sun

    2014-04-01

    Full Text Available We developed and applied a Cre-dependent, genetically modified rabies-based tracing system to map direct synaptic connections to specific CA1 neuron types in the mouse hippocampus. We found common inputs to excitatory and inhibitory CA1 neurons from CA3, CA2, the entorhinal cortex (EC, the medial septum (MS, and, unexpectedly, the subiculum. Excitatory CA1 neurons receive inputs from both cholinergic and GABAergic MS neurons, whereas inhibitory neurons receive a great majority of inputs from GABAergic MS neurons. Both cell types also receive weaker input from glutamatergic MS neurons. Comparisons of inputs to CA1 PV+ interneurons versus SOM+ interneurons showed similar strengths of input from the subiculum, but PV+ interneurons received much stronger input than SOM+ neurons from CA3, the EC, and the MS. Thus, rabies tracing identifies hippocampal circuit connections and maps how the different input sources to CA1 are distributed with different strengths on each of its constituent cell types.

  11. Estimating extracellular spike waveforms from CA1 pyramidal cells with multichannel electrodes.

    Science.gov (United States)

    Molden, Sturla; Moldestad, Olve; Storm, Johan F

    2013-01-01

    Extracellular (EC) recordings of action potentials from the intact brain are embedded in background voltage fluctuations known as the "local field potential" (LFP). In order to use EC spike recordings for studying biophysical properties of neurons, the spike waveforms must be separated from the LFP. Linear low-pass and high-pass filters are usually insufficient to separate spike waveforms from LFP, because they have overlapping frequency bands. Broad-band recordings of LFP and spikes were obtained with a 16-channel laminar electrode array (silicone probe). We developed an algorithm whereby local LFP signals from spike-containing channel were modeled using locally weighted polynomial regression analysis of adjoining channels without spikes. The modeled LFP signal was subtracted from the recording to estimate the embedded spike waveforms. We tested the method both on defined spike waveforms added to LFP recordings, and on in vivo-recorded extracellular spikes from hippocampal CA1 pyramidal cells in anaesthetized mice. We show that the algorithm can correctly extract the spike waveforms embedded in the LFP. In contrast, traditional high-pass filters failed to recover correct spike shapes, albeit produceing smaller standard errors. We found that high-pass RC or 2-pole Butterworth filters with cut-off frequencies below 12.5 Hz, are required to retrieve waveforms comparable to our method. The method was also compared to spike-triggered averages of the broad-band signal, and yielded waveforms with smaller standard errors and less distortion before and after the spike.

  12. Persistent sodium current properties in hippocampal CA1 pyramidal neurons of young and adult rats.

    Science.gov (United States)

    Lunko, Oleksii; Isaev, Dmytro; Maximyuk, Oleksandr; Ivanchick, Gleb; Sydorenko, Vadym; Krishtal, Oleg; Isaeva, Elena

    2014-01-24

    Persistent tetrodotoxin-sensitive sodium current (INaP) plays an important role in cellular and neuronal network excitability in physiological conditions and under different pathological circumstances. However, developmental changes in INaP properties remain largely unclear. In the present study using whole cell patch clamp technique we evaluated INaP properties in CA1 hippocampal pyramidal neurons isolated from young (postnatal day (P) 12-16) and adult (P60-75) rats. We show that the INaP density is substantially larger in the adult group. Although INaP inactivation characteristics were found to be similar in both groups, voltage dependence of INaP activation is shifted to more negative membrane potentials (young: -48.6±0.5mV vs. adult: -52.4±0.2mV, p<0.01). Our data indicates the increase of INaP contribution in the basal membrane sodium conductivity in the mature hippocampus.

  13. Roller Coaster Scanning reveals spontaneous triggering of dendritic spikes in CA1 interneurons.

    Science.gov (United States)

    Katona, Gergely; Kaszás, Attila; Turi, Gergely F; Hájos, Norbert; Tamás, Gábor; Vizi, E Sylvester; Rózsa, Balázs

    2011-02-01

    Inhibitory interneurons are considered to be the controlling units of neural networks, despite their sparse number and unique morphological characteristics compared with excitatory pyramidal cells. Although pyramidal cell dendrites have been shown to display local regenerative events--dendritic spikes (dSpikes)--evoked by artificially patterned stimulation of synaptic inputs, no such studies exist for interneurons or for spontaneous events. In addition, imaging techniques have yet to attain the required spatial and temporal resolution for the detection of spontaneously occurring events that trigger dSpikes. Here we describe a high-resolution 3D two-photon laser scanning method (Roller Coaster Scanning) capable of imaging long dendritic segments resolving individual spines and inputs with a temporal resolution of a few milliseconds. By using this technique, we found that local, NMDA receptor-dependent dSpikes can be observed in hippocampal CA1 stratum radiatum interneurons during spontaneous network activities in vitro. These NMDA spikes appear when approximately 10 spatially clustered inputs arrive synchronously and trigger supralinear integration in dynamic interaction zones. In contrast to the one-to-one relationship between computational subunits and dendritic branches described in pyramidal cells, here we show that interneurons have relatively small (∼14 μm) sliding interaction zones. Our data suggest a unique principle as to how interneurons integrate synaptic information by local dSpikes.

  14. Theta-frequency resonance in hippocampal CA1 neurons in vitro demonstrated by sinusoidal current injection.

    Science.gov (United States)

    Leung, L S; Yu, H W

    1998-03-01

    Sinusoidal currents of various frequencies were injected into hippocampal CA1 neurons in vitro, and the membrane potential responses were analyzed by cross power spectral analysis. Sinusoidal currents induced a maximal (resonant) response at a theta frequency (3-10 Hz) in slightly depolarized neurons. As predicted by linear systems theory, the resonant frequency was about the same as the natural (spontaneous) oscillation frequency. However, in some cases, the resonant frequency was higher than the spontaneous oscillation frequency, or resonance was found in the absence of spontaneous oscillations. The sharpness of the resonance (Q), measured by the peak frequency divided by the half-peak power bandwidth, increased from a mean of 0.44 at rest to 0.83 during a mean depolarization of 6.5 mV. The phase of the driven oscillations changed most rapidly near the resonant frequency, and it shifted about 90 degrees over the half-peak bandwidth of 8.4 Hz. Similar results were found using a sinusoidal function of slowly changing frequency as the input. Sinusoidal currents of peak-to-peak intensity of >100 pA may evoke nonlinear responses characterized by second and higher harmonics. The theta-frequency resonance in hippocampal neurons in vitro suggests that the same voltage-dependent phenomenon may be important in enhancing a theta-frequency response when hippocampal neurons are driven by medial septal or other inputs in vivo.

  15. Neonatal exposure to novelty enhances long-term potentiation in CA1 of the rat hippocampus.

    Science.gov (United States)

    Tang, Akaysha C; Zou, Bende

    2002-01-01

    Exposing rats to an enriched environment over an extended period of time has been shown to enhance hippocampal long-term potentiation (LTP). Whether such prolonged exposure to environmental manipulation is necessary for LTP enhancement and whether the environmentally induced enhancement can persist long after the cessation of the environmental manipulation remain unknown. Using a novelty exposure procedure modified from the method of neonatal handling, we exposed neonatal rats to a non-home environment for 3 min/day during the first 3 weeks of life. We examined the LTP of both population spikes and excitatory postsynaptic potentials (EPSPs), in vitro, in the CA1 of the hippocampus during adulthood (7-8 and 13-14 months of age). We found that both the LTP of population spikes and the LTP of EPSPs were enhanced among animals who experienced neonatal novelty exposure. These results demonstrate that effective environmental enhancement of LTP can be achieved by as brief and as transient a manipulation as a 3-min/day exposure over the first 3 weeks of life. The resulting enhancement can outlast the environmental manipulation by at least 1 year.

  16. THE KINETICS OF MULTIBRANCH INTEGRATION ON THE DENDRITIC ARBOR OF CA1 PYRAMIDAL NEURONS

    Directory of Open Access Journals (Sweden)

    Sunggu eYang

    2014-05-01

    Full Text Available The process by which synaptic inputs separated in time and space are integrated by the dendritic arbor to produce a sequence of action potentials is among the most fundamental signal transformations that takes place within the central nervous system. Some aspects of this complex process, such as integration at the level of individual dendritic branches, have been extensively studied. But other aspects, such as how inputs from multiple branches are combined, and the kinetics of that integration have not been systematically examined. Using a 3D digital holographic photolysis technique to overcome the challenges posed by the complexities of the 3D anatomy of the dendritic arbor of CA1 pyramidal neurons for conventional photolysis, we show that integration on a single dendrite is fundamentally different from that on multiple dendrites. Multibranch integration occurring at oblique and basal dendrites allows somatic action potential firing of the cell to faithfully follow the driving stimuli over a significantly wider frequency range than what is possible with single branch integration. However, multibranch integration requires greater input strength to drive the somatic action potentials. This tradeoff between sensitivity and kinetics may explain the puzzling report of the predominance of multibranch, rather than single branch, integration from in vivo recordings during presentation of visual stimuli.

  17. Thermoluminescence studies of bismuth doped Ba xCa 1- xS nanostructures

    Science.gov (United States)

    Singh, Surender; Lochab, S. P.; Kumar, Ravi; Singh, Nafa

    2011-01-01

    Bismuth doped Ba 1- xCa xS:Bi ( x=0-1) nanocrystallities have been prepared by the solid state reaction method and characterized by XRD and TEM. X-ray diffraction analysis shows the formation of the compounds in cubic structure at room temperature. Only partial replacement of Ba is possible and we found that Ba 0.5Ca 0.5S:Bi could not be prepared due to the difference between ionic radii of barium and calcium. Thermoluminescence studies of these samples after exposure to UV radiation have been carried out. The TL glow curve of Ba xCa 1 -xS:Bi has been found to be a simple structure with a single peak at 405, 428 and 503 K for x=1, 0.8 and 0, respectively. The kinetic parameters at various heating rates namely activation energy ( E), order of kinetics ( b) and frequency factor ( s) of the Ba 1- xCa xS:Bi ( x=0.2) (0.4 mol%) sample have been determined using Chen’s method. The deconvolution of curve was done using the GCD function suggested by Kitis. The effect of different heating rates and different amount of dose has also been discussed.

  18. Effects of lithium chloride on outward potassium currents in acutely isolated hippocampal CA1 pyramidal neurons

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chaofeng; DU Huizhi; YANG Pin

    2006-01-01

    Although lithium possesses neuroprotective functions, the molecular mechanism underlying its actions has not been fully elucidated. In the present paper, the effects of lithium chloride on voltage-dependent potassium currents in the CA1 pyramidal neurons acutely isolated from rat hippocampus were studied using the whole-cell patch-clamp technique. Depolarizing test pulses activated two components of outward potassium currents: a rapidly activating and inactivating component, IA and a delayed component, IK. Results showed that lithium chloride increased the amplitude of IA in a concentration-dependent manner. Half enhancement concentration (EC50) was 22.80±5.45 μmol·L-1. Lithium chloride of 25 μmol·L-1 shifted the steady-state activation curve and inactivation curve of IA to more negative potentials, but mainly affected the activation kinetics. The amplitude and the activation processes of IK were not affected by lithium chloride. The effects of lithium chloride on potassium channel appear to possess neuroprotective properties by Ca2+-lowing effects modulate neuronal excitability by activating IA in rat hippocampal neurons.

  19. In vivo blockade of neural activity alters dendritic development of neonatal CA1 pyramidal cells.

    Science.gov (United States)

    Groc, Laurent; Petanjek, Zdravko; Gustafsson, Bengt; Ben-Ari, Yehezkel; Hanse, Eric; Khazipov, Roustem

    2002-11-01

    During development, neural activity has been proposed to promote neuronal growth. During the first postnatal week, the hippocampus is characterized by an oscillating neural network activity and a rapid neuronal growth. In the present study we tested in vivo, by injecting tetanus toxin into the hippocampus of P1 rats, whether this neural activity indeed promotes growth of pyramidal cells. We have previously shown that tetanus toxin injection leads to a strong reduction in the frequency of spontaneous GABA and glutamatergic synaptic currents, and to a complete blockade of the early neural network activity during the first postnatal week. Morphology of neurobiotin-filled CA1 pyramidal cells was analyzed at the end of the first postnatal week (P6-10). In activity-reduced neurons, the total length of basal dendritic tree was three times less than control. The number, but not the length, of basal dendritic branches was affected. The growth impairment was restricted to the basal dendrites. The apical dendrite, the axons, or the soma grew normally during activity deprivation. Thus, the in vivo neural activity in the neonate hippocampus seems to promote neuronal growth by initiating novel branches.

  20. Methamphetamine reduces LTP and increases baseline synaptic transmission in the CA1 region of mouse hippocampus.

    Directory of Open Access Journals (Sweden)

    Jarod Swant

    Full Text Available Methamphetamine (METH is an addictive psychostimulant whose societal impact is on the rise. Emerging evidence suggests that psychostimulants alter synaptic plasticity in the brain--which may partly account for their adverse effects. While it is known that METH increases the extracellular concentration of monoamines dopamine, serotonin, and norepinephrine, it is not clear how METH alters glutamatergic transmission. Within this context, the aim of the present study was to investigate the effects of acute and systemic METH on basal synaptic transmission and long-term potentiation (LTP; an activity-induced increase in synaptic efficacy in CA1 sub-field in the hippocampus. Both the acute ex vivo application of METH to hippocampal slices and systemic administration of METH decreased LTP. Interestingly, the acute ex vivo application of METH at a concentration of 30 or 60 microM increased baseline synaptic transmission as well as decreased LTP. Pretreatment with eticlopride (D2-like receptor antagonist did not alter the effects of METH on synaptic transmission or LTP. In contrast, pretreatment with D1/D5 dopamine receptor antagonist SCH23390 or 5-HT1A receptor antagonist NAN-190 abrogated the effect of METH on synaptic transmission. Furthermore, METH did not increase baseline synaptic transmission in D1 dopamine receptor haploinsufficient mice. Our findings suggest that METH affects excitatory synaptic transmission via activation of dopamine and serotonin receptor systems in the hippocampus. This modulation may contribute to synaptic maladaption induced by METH addiction and/or METH-mediated cognitive dysfunction.

  1. Potassium currents in isolated CA1 neurons of the rat after kindling epileptogenesis.

    Science.gov (United States)

    Vreugdenhil, M; Wadman, W J

    1995-06-01

    Daily tetanic stimulation of the Schaffer collaterals generates an epileptogenic focus in area CA1 of the rat hippocampus, ultimately leading to generalized tonic-clonic convulsions (kindling). Potassium currents were measured under voltage-clamp conditions in pyramidal neurons, acutely dissociated from the focus of fully kindled rats, one day and six weeks after the last generalized seizure. Their amplitude, kinetics, voltage dependence and calcium dependence were compared with controls. With Ca2+ influx blocked by 0.5 mM Ni2+, the sustained current (delayed rectifier) and the transient current (A-current) were not different after kindling. Calcium influx evoked an additional fast transient current component. This transient calcium-dependent current component was increased by 154%, but only immediately after the seizure. A second, slow calcium-dependent potassium current component was dependent on the intracellular calcium level, set by the pipette as well as on calcium influx. The peak amplitude of this slow calcium-dependent current was under optimal calcium conditions not different after kindling, but we found indications that either calcium homeostasis or the calcium sensitivity of the potassium channels was affected by the kindling process. In contrast to the previously described enhancement of calcium current, kindling epileptogenesis did not change the total potassium current amplitude. The minor changes that were observed can be related either to changes in calcium current or to changes in intracellular calcium homeostasis.

  2. Nimodipine prevents early loss of hippocampal CA1 parvalbumin immunoreactivity after focal cerebral ischemia in the rat.

    Science.gov (United States)

    Benyó, Z; De Jong, G I; Luiten, P G

    1995-01-01

    The effect of focal cerebral ischemia induced by middle cerebral artery occlusion on hippocampal interneurons containing the calcium-binding protein parvalbumin (PV) was studied in rats. Four hours after the onset of ischemia, a reduced number of PV-immunoreactive (-ir) neurons was observed in the lateral part of the CA1 region, while PV-ir was not altered in the CA2 and CA3 areas. Pretreatment with the L-type Ca2+ channel blocker nimodipine prevented the ischemia-induced loss of PV-ir in the CA1, suggesting a role for L-type voltage sensitive calcium channels in the mechanism of early neuronal alterations in the hippocampus CA1 region after focal cerebral ischemia.

  3. Blockade of the AMPA receptor prevents CA1 hippocampal injury following severe but transient forebrain ischemia in adult rats.

    Science.gov (United States)

    Buchan, A M; Li, H; Cho, S; Pulsinelli, W A

    1991-11-11

    The cytoprotective effect of NBQX, a selective AMPA receptor antagonist, was tested following 10 min of severe forebrain ischemia using the 4-vessel occlusion model. Immediately, and at 15 and 30 min following reperfusion, adult Wistar rats received intraperitoneal injections of either saline (n = 5), 1 mg lithium chloride (n = 17) or 30 mg/kg of the lithium salt of NBQX (n = 18). In saline-treated animals 82 +/- 12% of CA1 hippocampal neurons were lost. Of those treated with lithium 70 +/- 23% were injured, while those given NBQX sustained only 40 +/- 34% CA1 necrosis (P less than 0.01). Twelve of 18 NBQX-treated animals had less than 30% CA1 injury as compared with 1 of 17 lithium-treated animals. The AMPA receptor may play a more important role than the NMDA receptor in selective ischemic necrosis of hippocampal neurons.

  4. Ischemic preconditioning decreases intracellular zinc accumulation induced by oxygen-glucose deprivation in gerbil hippocampal CA1 neurons.

    Science.gov (United States)

    Miyawaki, Takahiro; Yokota, Hidenori; Oguro, Keiji; Kato, Kengo; Shimazaki, Kuniko

    2004-05-27

    In normal gerbils, intracellular zinc ions ([Zn2+]i) and calcium ions ([Ca2+]i) accumulate in hippocampal CA1 neurons after global ischemia. We examined whether ischemic preconditioning modifies these changes in gerbil hippocampal slices. In normal slices, large increases in [Zn2+]i and [Ca2+]i were observed in the stratum radiatum of the CA1 area after oxygen-glucose deprivation. In preconditioned slices, there were significantly decreased peak levels of [Zn2+]i and [Ca2+]i in CA1. However, there were no differences in the peak levels of these ions in CA3 and dentate gyrus. These results suggest that modified [Zn2+]i and [Ca2+]i accumulation after an ischemic insult might be important for the mechanisms of ischemic tolerance induced by preconditioning.

  5. Zbtb20-Induced CA1 Pyramidal Neuron Development and Area Enlargement in the Cerebral Midline Cortex of Mice

    DEFF Research Database (Denmark)

    Nielsen, Jakob V; Blom, Jonas B; Noraberg, Jens

    2010-01-01

    that are innervated by Schaffer collateral projections in ectopic strata oriens and radiatum. The Zbtb20-transformed neurons express Bcl11B, Satb2, and Calbindin-D28k, which are markers of adult CA1 pyramidal neurons. Downregulation of Zbtb20 expression by RNA interference impairs the normal maturation of CA1...... pyramidal neurons resulting in deficiencies in Calbindin-D28k expression and in reduced apical dendritic arborizations in stratum lacunosum moleculare. Overall, the results show that Zbtb20 is required for various aspects of CA1 pyramidal neuron development such as the postnatal extension of apical...... dendritic arbors in the distal target zone and the subtype differentiation of Calbindin-D28k-positive subsets. They further suggest that Zbtb20 plays a role in arealization of the midline cortex....

  6. Colon perforation after esophagogastroduodenoscopy in an asymptomatic diverticulitis patient

    Directory of Open Access Journals (Sweden)

    Li-Wen Huang

    2016-03-01

    Full Text Available Esophagogastroduodenoscopy (EGD is regarded as a relatively safe procedure; however, it carries a very low incidence of severe adverse events. Perforation is a rare complication of EGD, and it may further lead to pneumoperitoneum or pneumoretroperitoneum. The occurrence of large bowel perforation after EGD is extremely rare, and it has never been reported in the international literature. Herein, we present a case of concurrence of pneumoperitoneum and pneumoretroperitoneum as a result of sigmoid perforation after EGD. In our case, the probable mechanism of the perforation may have stemmed from the excessive inflation of air that passed through the gastrointestinal tract to the sigmoid colon, causing the increased intraluminal pressure, and then prompting a healed asymptomatic diverticulitis leak again.

  7. Modeling natural convection heat transfer from perforated plates

    Institute of Scientific and Technical Information of China (English)

    Zan WU; Wei LI; Zhi-jian SUN; Rong-hua HONG

    2012-01-01

    Staggered pattern perforations are introduced to isolated isothermal plates,vertical parallel isothermal plates,and vertical rectangular isothermal fins under natural convection conditions.The performance of perforations was evaluated theoretically based on existing correlations by considering effects of ratios of open area,inclined angles,and other geometric parameters.It was found that staggered pattern perforations can increase the total heat transfer rate for isolated isothermal plates and vertical parallel plates,with low ratios of plate height to wall-to-wall spacing (H/s),by a factor of 1.07 to 1.21,while only by a factor of 1.03 to 1.07 for vertical rectangular isothermal fins,and the magnitude of enhancement is proportional to the ratio of open area.However,staggered pattern perforations are detrimental to heat transfer enhancement of vertical parallel plates with large H/s ratios.

  8. Perforated diverticulitis of the sigmoid colon causing a subcutaneous emphysema

    Directory of Open Access Journals (Sweden)

    Radwan Kassir

    2014-01-01

    CONCLUSION: This physical sign may be of especial value in elderly patient groups amongst whom perforation may be less clinically obvious. General surgeons should bear in mind this rare complication of colonic diverticulosis.

  9. Wave Damping over a Perforated Plate with Water Chambers

    Institute of Scientific and Technical Information of China (English)

    ZHU Shutang

    2006-01-01

    The movement of waves propagating over a horizontally submerged perforated plate with waterfilled chambers bellow the plate was investigated by using linear potential theory. The analytical solution was compared with laboratory experiments on wave blocking. The analysis of the wave energy dissipation on the perforated bottom surface shows that the effects of the perforated plate on thewave motion depend mainly on the plate porosity, the wave height, and the wave period. The wave number is a complex number when the wave energy dissipation on the perforated plate is considered. The real part of the wave number refers to the spatial periodicity while the imaginary part represents the damping modulus. The characteristics of the wave motion were explored for several possible conditions.

  10. Risk factors for reintervention after surgery for perforated gastroduodenal ulcer

    DEFF Research Database (Denmark)

    Hasselager, R B; Lohse, N; Duch, P;

    2016-01-01

    BACKGROUND: Perforated gastroduodenal ulcer carries a high mortality rate. Need for reintervention after surgical repair is associated with worse outcome, but knowledge on risk factors for reintervention is limited. The aim was to identify prognostic risk factors for reintervention after perforated...... gastroduodenal ulcer in a nationwide cohort. METHODS: All patients treated surgically for perforated gastroduodenal ulcer in Denmark between 2003 and 2014 were included using data from the Danish Clinical Register of Emergency Surgery. Potential risk factors for reintervention were assessed, and their crude...... and adjusted associations calculated by the competing risks subdistribution hazards approach. RESULTS: A total of 4086 patients underwent surgery for perforated gastroduodenal ulcer during the study interval. Median age was 71·1 (i.q.r. 59·6-81·0) years and the overall 90-day mortality rate was 30·8 per cent...

  11. Case of choledochal cyst presenting as perforation abdomen

    Directory of Open Access Journals (Sweden)

    Gobbur RH, Baradol R RV, Nyammannavar

    2013-01-01

    Full Text Available Choledochal cyst is an uncommon congenital anomaly of Hepoatobiliary system. It is a case of choledocal cyst presenting as perforation and biliary ascites which is rare in infants. Clinical picture: An infant was admitted at BLDE hospital with history of convulsion and breathlessness, on examination child had abdominal distension. Investigations like erect X ray abdomen done which revealed ascites with features of peritonitis, so exploratory laparotomy done which showed a choledochal cyst with perforation causing biliary ascites. Treatment: Child was treated in the pediatric intensive care unit for convulsion. Exploratory laparotomy done and the perforated choledochal cyst was sutured and drain placed in situ. The child improved from 2nd post operative day. Conclusion: Choledochal cyst can present as perforation, biliary ascites and peritonitis in infants. Therefore treatment should be oriented to this aspect also.

  12. CT findings of hepatic abscess arising from perforated acute cholecystitis

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sang Hee; Lee, Kyoung Soo; Lee, Jin Seoung; Lee, Moon Gyu; Chung, Young Hwa; Lee, Young Sang; Lee, Sung Gyu; Auh, Yong Ho [Ulsan Univ. College of Medicine, Seoul (Korea, Republic of)

    1996-01-01

    The purpose of this study was to report the CT findings of four patients with hepatic abscess secondary to perforated acute cholecystitis. We retrospectively reviewed the CT findings of four patients with surgically proven hepatic abscess secondary to perforated acute cholecystitis. CT findings were analysed with respect to the observation of the gallbladder, pericholecystic space, hepatic lesions, and peritoneal cavity. All patients underwent cholecystectomy, with drainage of the hepatic abscess. CT findings of hepatic abscess secondary to perforated acute cholecystitis were hypodense mass formation in the pericholecystic space(n=3), irreguarity and wall defect of Gallbladder(n=4), thickened Gallbladder wall(n=4), stone with debris(n=4), and local or diffuse infiltration of the pericholecystic area(n=3), omentum, and mesentery. CT was helpful in diagnosing the hepatic abscess secondary to perforated acute cholecystitis.

  13. Laparoscopic Lavage for Perforated Diverticulitis With Purulent Peritonitis

    DEFF Research Database (Denmark)

    Thornell, Anders; Angenete, Eva; Bisgaard, Thue

    2016-01-01

    BACKGROUND: Perforated diverticulitis with purulent peritonitis has traditionally been treated with open colon resection and stoma formation with risk for reoperations, morbidity, and mortality. Laparoscopic lavage alone has been suggested as definitive treatment. OBJECTIVE: To compare laparoscopic...

  14. Selective approach in the treatment of esophageal perforations

    NARCIS (Netherlands)

    Amir, AI; von Dullemen, H; Plukker, JTM

    2004-01-01

    Background: Treatment of esophageal perforation remains controversial and recommendations vary from initially non-operative to aggressive surgical management. Several factors are responsible for this life-threatening event, which has led to more individualized treatment ensuring adequate pleuromedia

  15. Gastric perforation due to foreign body ingestion mimicking acute cholecystitis.

    Science.gov (United States)

    Henneman, Daniel; Bosman, Willem-Maarten; Ritchie, Ewan D; van den Bremer, Jephta

    2015-03-04

    An 82-year-old man presented with signs and symptoms that were suggestive of acute cholecystitis. He underwent a laparoscopic cholecystectomy. During the intervention, a wooden foreign body was removed from the infiltrated omentum, probably after it had perforated the gastric antrum. The gastric perforation had led to a secondary infection of the gallbladder. The presumed gastric perforation was treated conservatively, and the patient recovered well and was discharged after 7 days. Secondary inflamed gallbladders are rare; the current case is, to the best of our knowledge, the first case reporting a secondary infection of the gallbladder due to a gastric perforation. Clinicians should be aware of possible ingestion of foreign bodies in elderly patients wearing dental prosthetic devices.

  16. Laparoscopic lavage for perforated diverticulitis: a population analysis.

    LENUS (Irish Health Repository)

    Rogers, Ailín C

    2012-09-01

    Laparoscopic lavage has shown promising results in nonfeculent perforated diverticulitis. It is an appealing strategy; it avoids the complications associated with resection. However, there has been some reluctance to widespread uptake because of the scarcity of large-scale studies.

  17. Perforation forces of the intact porcine anterior lens capsule.

    Science.gov (United States)

    Ullrich, Franziska; Lussi, Jonas; Felekis, Dimitrios; Michels, Stephan; Petruska, Andrew J; Nelson, Bradley J

    2016-09-01

    During the first step of cataract surgery, the lens capsule is perforated and a circular hole is created with a sharp instrument, a procedure called capsulorhexis. To develop automated systems that can assist ophthalmologists during capsulorhexis, the forces required must be quantified. This study investigates perforation forces of the central anterior lens capsule in porcine eyes, which are used as a conservative model for the human eye. A micro-mechanical characterisation method is presented that measures capsular bag perforation forces with a high precision positioning and high-resolution force sensing system. The force during perforation of the anterior lens capsule was measured with various sized needles and indentation speeds and is found to be 15-35mN. A bio-mechanical model is identified that describes an exponential correlation between indentation force and depth, indicating strain hardening behaviour of the porcine anterior lens capsule.

  18. Oblique perforation of thick metallic plates by rigid projectiles

    Institute of Scientific and Technical Information of China (English)

    Xiaowei Chen; Qingming Li; Saucheong Fan

    2006-01-01

    Oblique perforation of thick metallic plates by rigid Drojectiles with various nose shapes is studied in this paper.Two perforation mechanisms,i.e., the hole enlargement for a sharp projectile nose and the plugging formation for a blunt projectile nose,are considered in the proposed analytical model.It is shown that the perforation of a thick plate is dominated by several non-dimensional numbers,i.e., the impact function,the geometry function of projectile,the non-dimensional thickness of target and the impact obliquity.Explicit formulae are obtained to predict the ballistic limit.residual velocity and directional change for the oblique perforation of thick metallic plates.The proposed model is able to predict the critical condition for the occurrence of ricochet.The proposed model is validated by comparing the predictions with other existing models and independent experimental data.

  19. Activation of Ih and TTX-sensitive sodium current at subthreshold voltages during CA1 pyramidal neuron firing.

    Science.gov (United States)

    Yamada-Hanff, Jason; Bean, Bruce P

    2015-10-01

    We used dynamic clamp and action potential clamp techniques to explore how currents carried by tetrodotoxin-sensitive sodium channels and HCN channels (Ih) regulate the behavior of CA1 pyramidal neurons at resting and subthreshold voltages. Recording from rat CA1 pyramidal neurons in hippocampal slices, we found that the apparent input resistance and membrane time constant were strongly affected by both conductances, with Ih acting to decrease apparent input resistance and time constant and sodium current acting to increase both. We found that both Ih and sodium current were active during subthreshold summation of artificial excitatory postsynaptic potentials (EPSPs) generated by dynamic clamp, with Ih dominating at less depolarized voltages and sodium current at more depolarized voltages. Subthreshold sodium current-which amplifies EPSPs-was most effectively recruited by rapid voltage changes, while Ih-which blunts EPSPs-was maximal for slow voltage changes. The combined effect is to selectively amplify rapid EPSPs. We did similar experiments in mouse CA1 pyramidal neurons, doing voltage-clamp experiments using experimental records of action potential firing of CA1 neurons previously recorded in awake, behaving animals as command voltages to quantify flow of Ih and sodium current at subthreshold voltages. Subthreshold sodium current was larger and subthreshold Ih was smaller in mouse neurons than in rat neurons. Overall, the results show opposing effects of subthreshold sodium current and Ih in regulating subthreshold behavior of CA1 neurons, with subthreshold sodium current prominent in both rat and mouse CA1 pyramidal neurons and additional regulation by Ih in rat neurons.

  20. Gallstone spillage caused by spontaneously perforated hemorrhagic cholecystitis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    There are occasional incidences of gallstone spillage during laparoscopic cholecystectomy, and there have been frequent reports on such a topic in the literature. To the best of our knowledge, however, there have been no reports about spilled stones caused by spontaneously perforated hemorrhagic cholecystitis. Here, we report the radiologic findings of spilled stones caused by spontaneously perforated hemorrhagic cholecystitis in a 55-year-old man.

  1. Radiologic findings of perforated jejunal diverticulitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Jeong Hwa; Lee, Dong Ho; Kim, Hyoung Jung; Lim, Joo Won; Ko, Young Tae; Park, Yong Koo [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    2006-04-15

    We report a case of perforated jejunal diverticulitis in a 68-year-old man with iatrogenic Cushing's syndrome. The patient presented with right upper abdominal pain. Ultrasonography showed a hypoechoic structure connected to a small bowel loop, and subsequent CT examination showed multiple diverticula in proximal jejunal loops with free air trapped within the mesenteric leaf. Segmental resection of the jejunal loop confirmed jejunal diverticulitis with perforation.

  2. Colonoscopic perforation:Incidence,risk factors,management and outcome

    Institute of Scientific and Technical Information of China (English)

    Varut; Lohsiriwat

    2010-01-01

    This review discusses the incidence,risk factors,management and outcome of colonoscopic perforation(CP).The incidence of CP ranges from 0.016% to 0.2% following diagnostic colonoscopies and could be up to 5% following some colonoscopic interventions.The perforations are frequently related to therapeutic colonoscopies and are associated with patients of advanced age or with multiple comorbidities.Management of CP is mainly based on patients' clinical grounds and their underlying colorectal diseases.Current t...

  3. PERFORATED DUODENAL ULCER ASSOCIATED WITH SITUS INVERSUS AND DEXTROCARDIA.

    Science.gov (United States)

    Ibrahim, Mumtaz; Hussain, Dildar; Waheed, Seema; Tahir, Raazia; Haider, Ghulam; Ali, Nauvan; Sarfraz, Shahid Latif

    2016-01-01

    A 32 years old gentleman, presented in emergency department, with complaints of sudden onset of severe upper abdominal pain, associated with nausea and vomiting. He was a known case of acid peptic disease. His abdominal examination showed signs of peritonitis. X-ray chest showed pneumoperitoneum, with dextrocardia. Ultrasound showed situs inversus. Exploration confirmed the diagnosis of perforated ulcer and situs inversus. Grahm's patch repair of perforation was done. His postoperative recovery was smooth.

  4. Endoscopic Treatment of Gastrointestinal Perforations, Leaks, and Fistulae.

    Science.gov (United States)

    Rustagi, Tarun; McCarty, Thomas R; Aslanian, Harry R

    2015-01-01

    Gastrointestinal leaks and fistulae are common postoperative complications, whereas intestinal perforation more commonly complicates advanced endoscopic procedures. Although these complications have classically been managed surgically, there exists an ever-expanding role for endoscopic therapy and the involvement of advanced endoscopists as part of a multidisciplinary team including surgeons and interventional radiologists. This review will serve to highlight the innovative endoscopic interventions that provide an expanding range of viable endoscopic approaches to the management and therapy of gastrointestinal perforation, leaks, and fistulae.

  5. Development of synaptic connectivity onto interneurons in stratum radiatum in the CA1 region of the rat hippocampus

    Directory of Open Access Journals (Sweden)

    Riebe Ilse

    2012-01-01

    Full Text Available Abstract Background The impact of a given presynaptic neuron on the firing probability of the postsynaptic neuron critically depends on the number of functional release sites that connect the two neurons. One way of determining the average functional synaptic connectivity onto a postsynaptic neuron is to compare the amplitudes of action potential dependent spontaneous synaptic currents with the amplitude of the synaptic currents that are independent of action potentials ("minis". With this method it has been found that average synaptic connectivity between glutamatergic CA3 and CA1 pyramidal cells increases from single connections in the neonatal rat, to multiple connections in the young adult rat. On the other hand, γ-aminobutyric acid (GABAergic interneurons form multiple connections onto CA1 pyramidal cells already in the neonatal rat, and the degree of multiple GABAergic connectivity is preserved into adulthood. In the present study, we have examined the development of glutamate and GABA connectivity onto GABAergic CA1 stratum radiatum interneurons in the hippocampal slice, and compared this to the connectivity onto CA1 pyramidal neurons. Results In GABAergic interneurons in the CA1 stratum radiatum, irrespective of developmental stage, we found that the average amplitude of action potential dependent spontaneous AMPA receptor-mediated synaptic currents were of the same magnitude as the mini AMPA receptor mediated synaptic currents. This finding indicates that these GABAergic interneurons, in contrast to the CA1 pyramidal neurons, preserve single glutamate connectivity throughout development. For GABA connectivity, on the other hand, we found multiple functional synaptic connections onto the interneurons, as onto the pyramidal cells. Conclusions The results presented here confirm that glutamate and GABA synaptic connectivity develop very differently in the hippocampal CA1 region. Thus, whereas average GABA connectivity is multiple

  6. Delayed Diagnosis of Pharyngeal Perforation following Exploding Tyre Blast Barotrauma

    Directory of Open Access Journals (Sweden)

    Samantha M. Field

    2014-01-01

    Full Text Available Introduction. Pharyngoesophageal perforation secondary to barotrauma is a rare phenomenon that can have serious complications if identified late. It is challenging to detect due to nonspecific symptoms. We present a case in which detection proved difficult leading to delayed diagnosis. Case Report. A 27-year-old mechanic presented with haemoptysis, dysphonia, and odynophagia after a car tyre exploded in his face. Flexible nasoendoscopy (FNE revealed blood in the pharynx, thought to represent mucosal haemorrhage. Initial treatment consisted of IV dexamethasone and antibiotics. After 3 days, odynophagia persisted prompting a CT scan. This revealed a defect in the posterior hypopharynx and surgical emphysema in the deep neck tissues. Contrast swallow confirmed posterior hypopharyngeal leak. NG feeding was commenced until repeated contrast swallow confirmed resolution of the defect. Discussion. Prompt nonsurgical management of pharyngoesophageal perforation has good outcomes but untreated perforation can have serious complications. FNE should be performed routinely, but only a contrast swallow can diagnose a functional perforation. Clinicians should have a high index of clinical suspicion when patients present with barotrauma and odynophagia. Patients should be kept nil by mouth until perforation has been excluded. Conclusion. When faced with cases of facial barotrauma, clinicians should have a low threshold for further imaging to exclude pharyngoesophageal perforation.

  7. Inferior Flap Tympanoplasty: A Novel Technique for Anterior Perforation Closure

    Directory of Open Access Journals (Sweden)

    Haim Gavriel

    2013-01-01

    Full Text Available Objective. To report a novel tympanoplasty modification for anterior tympanic membrane perforation closure. Materials and Methods. A prospective study on 13 patients who underwent inferior tympanoplasty between December 2008 and May 2011 was carried out. In our technique, an inferior rather than a posterior flap is raised and the graft is laid from the inferior direction to obtain better access to the anterior part of the tympanic membrane perforation and provide better support. Results. A total of 13 patients underwent the novel inferior tympanoplasty technique with a mean age of 33 years. Six patients had undergone tympanoplasties and/or mastoidectomies in the past, 3 in the contralateral ear. A marginal perforation was observed in 3 cases, total perforation in 2 and subtotal in 1 case. The mean preoperative pure-tone average was 40.4 dB (10 to 90 dB, compared to 26.5 dB (10 to 55 dB postoperatively. All perforations were found to be closed but one (92.3% success rate. Conclusions. The inferior tympanoplasty technique provides a favorable outcome in terms of tympanic membrane closure and hearing improvement for anterior perforations, even in difficult and complex cases. It is based on a well-known technique and is easy to implement.

  8. Laparoscopic repair for perforated peptic ulcers with U-CLIP®

    Directory of Open Access Journals (Sweden)

    Fontana Diego

    2009-07-01

    Full Text Available Abstract Background The literature established that, in patients without Boey's risk factors, laparoscopic repair of perforated peptic ulcers, compared to open repair, is associated to lower wound infection rate, less analgesic use, reduction in post operative pain, shorter hospital stay. Some of the main drawbacks are length of operative time and laparoscopic surgeon's experience in intracorporeal knotting. We, for first, report our preliminary experience of perforated peptic ulcers' laparoscopic repair using Medtronic U-Clip®. Methods From January 2008 to June 2008 we performed laparoscopic repair of perforated peptic ulcers using Medtronic U-Clip® in 10 consecutive patients (6 men and 4 women, from 20 to 65 years-old of age. All the patients presented with iuxtapyloric perforated peptic ulcer, not greater than 10 mm, without signs of sepsis, free from major illnesses. The mini-invasive procedure was performed both by skilled and non-skilled laparoscopic surgeons under experts' surveillance. After it was recognized, perforation was sutured using U-Clip® in a full-thickness manner. Results and Discussion We reported no surgical complications in the peri-operative period. The clinical outcome and time needed to perform the intervention didn't change between skilled and non-skilled surgeons. The follow-up at 30 days was good. Conclusion In our experience, the anastomotic device U-Clip® simplifies laparoscopic repair of perforated peptic ulcer, avoiding the need to perform knots and making the procedure safe and easier.

  9. Perforated peptic ulcer following gastric bypass for obesity.

    Science.gov (United States)

    Macgregor, A M; Pickens, N E; Thoburn, E K

    1999-03-01

    Peptic ulcer in the excluded segment of a gastric bypass performed in the management of morbid obesity has only rarely been reported in the literature. The purpose of this study is to review our experience with the condition in a series of 4300 patients who underwent gastric-restrictive surgery between 1978 and 1997. Eleven patients presented with acute perforation of a peptic ulcer in the excluded gastric segment. Nine ulcers were duodenal, one was gastric, and one patient had both gastric and duodenal perforations. The time between primary gastric-restrictive surgery and ulcer perforation varied from 20 days to 12 years. All patients presented with upper abdominal pain. The classical radiological sign of perforated peptic ulcer, free air under the diaphragm, did not occur in any patient. Nine patients were initially treated by primary closure of the perforation with subsequent definitive ulcer therapy by vagotomy, pyloroplasty, or gastrectomy. One case, initially treated elsewhere, was managed by placement of a Malecot catheter through the duodenal perforation, gastrostomy, and peritoneal drainage. One recent case remains symptom-free on H2 blockers after simple closure. There was no mortality. Six cases were previously reported in the literature with a 33 per cent mortality rate.

  10. Nonobstructing Colonic Dilatation and Colon Perforations Following Renal Transplantation

    Science.gov (United States)

    Koneru, Baburao; Selby, Rick; O’Hair, Daniel P.; Tzakis, Andreas G.; Hakala, Thomas R.; Starzl, Thomas E.

    2010-01-01

    Nonobstructing colonic dilatation has not been commonly reported following renal transplantation, and colon perforations carry a high morbidity and mortality in this population. During a 7-year period, nonobstructing colonic dilatation developed in 13 adults 1 to 13 days after renal transplantation. Twelve (92%) of the 13 had poorly functioning allografts. Five (83%) of the 6 with and 2 (29%) of the 7 without colonoscopy had resolution of nonobstructing colonic dilatation. Of the seven right-sided colon perforations during this period, six were associated with nonobstructing colonic dilatation. An additional 4 patients had diverticular perforations in the left colon. Of a total of 11 patients with colon perforation, 7 had surgery within 24 hours of the perforation and 6 (86%) of these survived. Only 1 (25%) of the 4 having surgery more than 24 hours later survived. Six of the survivors retained functioning allografts. Nonobstructing colonic dilatation seems to be a potential complication of poor graft function after renal transplantation, and colonoscopy is effective in its treatment. In patients with colon perforations, early surgery and reduced immunosuppression are essential in decreasing mortality. PMID:2331220

  11. Late anastomotic perforation following surgery for gastric neuroendocrine tumor complicated by perforated duodenal ulcer: a case report.

    Science.gov (United States)

    Han, Jun; He, Zhenyu

    2013-03-01

    Neuroendocrine tumors (NETs) are a group of neoplasms that are characterized by the secretion of a variety of hormones and diverse clinical syndromes. NETs are considered to be rare, but the incidence of NETs has increased rapidly in recent years. NETs provide a clinical challenge for physicians because they comprise a heterogeneous group of malignancies with a wide range of morphological, functional, and behavioral characteristics. Subtotal gastrectomy with Billroth II reconstruction is the mainstay of therapy in the management of gastric NETs complicated by perforated duodenal ulcer. Late perforation of anastomotic stoma as a long-term complication has been rarely reported. Here, we report a case of anastomotic perforation 5 years after subtotal gastrectomy due to perforated duodenal ulcer and gastric NETs.

  12. Hippocampal CA1 lacunosum-moleculare interneurons: modulation of monosynaptic GABAergic IPSCs by presynaptic GABAB receptors.

    Science.gov (United States)

    Khazipov, R; Congar, P; Ben-Ari, Y

    1995-11-01

    1. Whole cell patch-clamp recordings were employed to characterize monosynaptic inhibitory postsynaptic currents (IPSCs) in morphologically and electrophysiologically identified interneurons located in the stratum lacunosum moleculare, or near the border of the stratum radiatum (LM interneurons), in the CA1 region of hippocampal slices taken from 3- to 4-wk-old rats. Monosynaptic IPSCs, evoked in the presence of glutamate receptor antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 20 microM) and D-2-amino-5-phosphopentanoate (APV; 50 microM) were biphasic. The gamma-aminobutyric acid-A (GABAA) receptor antagonist, bicuculline (20 microM), blocked the fast IPSC, and the slow IPSC was blocked by the GABAB receptor antagonist CGP35348 (500 microM). 2. Monosynaptic IPSCs were evoked by electrical stimulation in several distant regions including the stratum radiatum, the stratum oriens, the stratum lacunosum-moleculare, and the molecular layer of dentate gyrus, suggesting an extensive network of inhibitory interneurons in the hippocampus. In paired recordings of CA1 interneurons and pyramidal cells, IPSCs were evoked by electrical stimulation of most of these distal regions with the exception of the molecular layer of dentate gyrus, which evoked an IPSC only in LM interneurons. 3. Frequent (> 0.1 Hz) stimulation depressed the evoked IPSCs. With a paired-pulse protocol, the second IPSC was depressed and the maximal depression (40-50%) was observed with an interstimulus interval of 100-200 ms. 4. The GABAB receptor agonist baclofen (1 microM) reduced the amplitude of evoked IPSCs and the paired-pulse depression of the second IPSC. The GABAB receptor antagonist CGP35348 (0.5-1 mM) had no significant effect on the amplitude of isolated IPSCs. However, CGP35348 reduced but did not fully block paired-pulse depression, suggesting that this depression is partly due to the activation of presynaptic GABAB receptors. 5. The paired-pulse depression depended on the level of

  13. Intraocular cilia associated with perforating injury

    Directory of Open Access Journals (Sweden)

    Gopal Lingam

    2000-01-01

    Full Text Available Purpose: To report a case series of penetrating injury complicated by occurrence of intraocular cilia. Methods: Retrospective analysis of charts of 11 eyes of 11 patients with penetrating injury and intraocular cilia, presenting between September 1978 and November 1998. Ten eyes underwent surgery for trauma-related problems such as cataract, vitritis, retinal detachment etc., at which time intraocular cilia were removed. One eye did not have surgery and continues to harbour cilia at the posterior perforation site. Results: Metallic wire was responsible for injury in 6 of 11 eyes with intraocular cilia. Five eyes had significant intraocular inflammation. The cilia were located in the anterior segment in 4 eyes; in the posterior segment in 6 eyes and in both in one eye. At the last follow up, 72.7% had 6/18 or better vision. Poor vision in the rest was due to recurrent retinal detachment (2 eyes and macular scarring (1 eye. Conclusion: Intraocular cilia are more commonly associated with injury by a metallic wire. The presentation and management of an injured eye does not seem to be influenced by the presence of cilia in the eye.

  14. Estimating extracellular spike waveforms from CA1 pyramidal cells with multichannel electrodes.

    Directory of Open Access Journals (Sweden)

    Sturla Molden

    Full Text Available Extracellular (EC recordings of action potentials from the intact brain are embedded in background voltage fluctuations known as the "local field potential" (LFP. In order to use EC spike recordings for studying biophysical properties of neurons, the spike waveforms must be separated from the LFP. Linear low-pass and high-pass filters are usually insufficient to separate spike waveforms from LFP, because they have overlapping frequency bands. Broad-band recordings of LFP and spikes were obtained with a 16-channel laminar electrode array (silicone probe. We developed an algorithm whereby local LFP signals from spike-containing channel were modeled using locally weighted polynomial regression analysis of adjoining channels without spikes. The modeled LFP signal was subtracted from the recording to estimate the embedded spike waveforms. We tested the method both on defined spike waveforms added to LFP recordings, and on in vivo-recorded extracellular spikes from hippocampal CA1 pyramidal cells in anaesthetized mice. We show that the algorithm can correctly extract the spike waveforms embedded in the LFP. In contrast, traditional high-pass filters failed to recover correct spike shapes, albeit produceing smaller standard errors. We found that high-pass RC or 2-pole Butterworth filters with cut-off frequencies below 12.5 Hz, are required to retrieve waveforms comparable to our method. The method was also compared to spike-triggered averages of the broad-band signal, and yielded waveforms with smaller standard errors and less distortion before and after the spike.

  15. Adenosine actions on CA1 pyramidal neurones in rat hippocampal slices.

    Science.gov (United States)

    Greene, R W; Haas, H L

    1985-09-01

    Intracellular recordings with a bridge amplifier of CA1 pyramidal neurones in vitro were employed to study the mechanisms of action of exogenously applied adenosine in the hippocampal slice preparation of the rat. Adenosine enhanced the calcium-dependent, long-duration after-hyperpolarization (a.h.p.) at least in part by a reduction in the rate of decay of the a.h.p. Both the reduced rate of decay and that of the control can be described with a single exponential. Antagonism of the calcium-dependent potassium current (and as a result, the a.h.p.) by bath application of CdCl2 or intracellular injection of EGTA (ethyleneglycolbis-(beta-aminoethyl ether)N,N'-tetraacetic acid) did not reduce the adenosine-evoked hyperpolarization or decrease in input resistance. Similarly, TEA (tetraethylammonium), which antagonizes both the voltage- and calcium-sensitive, delayed, outward rectification, had no effect on the adenosine-evoked changes in resting membrane properties. Adenosine did not affect the early, transient, outward rectification. During exposure to 4-aminopyridine (4-AP) in concentrations sufficient to antagonize this early rectification, the changes in resting membrane properties evoked by adenosine were unaffected. We conclude that the enhancement of the a.h.p. and accommodation by adenosine may be mediated by a change in the regulation of intracellular calcium. However, the mechanism responsible for the hyperpolarization and decrease in input resistance evoked by adenosine is both calcium and voltage insensitive. Thus, it appears distinct from that mediating the enhancement of the a.h.p. and accommodation.

  16. Distinct axo-somato-dendritic distributions of three potassium channels in CA1 hippocampal pyramidal cells.

    Science.gov (United States)

    Kirizs, Tekla; Kerti-Szigeti, Katalin; Lorincz, Andrea; Nusser, Zoltan

    2014-06-01

    Potassium channels comprise the most diverse family of ion channels and play critical roles in a large variety of physiological and pathological processes. In addition to their molecular diversity, variations in their distributions and densities on the axo-somato-dendritic surface of neurons are key parameters in determining their functional impact. Despite extensive electrophysiological and anatomical investigations, the exact location and densities of most K(+) channels in small subcellular compartments are still unknown. Here we aimed at providing a quantitative surface map of two delayed-rectifier (Kv1.1 and Kv2.1) and one G-protein-gated inwardly rectifying (Kir3.2) K(+) channel subunits on hippocampal CA1 pyramidal cells (PCs). Freeze-fracture replica immunogold labelling was employed to determine the relative densities of these K(+) channel subunits in 18 axo-somato-dendritic compartments. Significant densities of the Kv1.1 subunit were detected on axon initial segments (AISs) and axon terminals, with an approximately eight-fold lower density in the latter compartment. The Kv2.1 subunit was found in somatic, proximal dendritic and AIS plasma membranes at approximately the same densities. This subunit has a non-uniform plasma membrane distribution; Kv2.1 clusters are frequently adjacent to, but never overlap with, GABAergic synapses. A quasi-linear increase in the Kir3.2 subunit density along the dendrites of PCs was detected, showing no significant difference between apical dendritic shafts, oblique dendrites or dendritic spines at the same distance from the soma. Our results demonstrate that each subunit has a unique cell-surface distribution pattern, and predict their differential involvement in synaptic integration and output generation at distinct subcellular compartments.

  17. EVALUATION OF “SEPS” PROCEDURE IN THE MANAGEMENT OF PRIMARY VARICOSE VEINS WITH INCOMPETENT LOWER LIMB PERFORATOR

    Directory of Open Access Journals (Sweden)

    Shaik Ahmad

    2016-03-01

    Full Text Available BACKGROUND Varicose veins affect at least 1 out of 5 in the world and the cost of health care for the society is significant. In a developing country like India, study encompassing the clinical evaluation and management of lower limb varicose veins on the conventional lines seems a necessity to improve the quality care with the available resources. OBJECTIVES To study the relation between site of incompetence and complications, pattern of complications, surgical management and its outcome for lower limb varicose veins. METHODS A total 26 number of patients with primary varicose veins admitted, investigated, operated and followed up. Final outcome evaluated. All the information was taken down in the proforma, designed for the study. RESULTS In the study, it was noted that the varicose veins affect younger, adult, and middle age population. (20 to 60 years. Majority of the patients were male (84.60%. Perforator incompetence only = 42.3% (n=11. Perforator incompetence + saphenofemoral/saphenopopliteal incompetence seen in 57.7%. Long saphenous vein involvement was seen in 90.5% of the patients and both LSV and SSV involvement in 9.5%. A greater portion of the patients had combined valvular incompetence (69.56%. The mean ulcer healing time in our study was 2.8 weeks following surgery (90%. Residual incompetent perforators are seen in 7.6% (n=2. New incompetent perforators seen in 7.6% (n=2. Postoperative wound infection of the incision of SPJ ligation was seen in 3.8% (n=1 of the patients, but not the SEPS wound infection and the total complication rate was 3.85%. The mean postoperative stay for patients undergoing SEPS procedure alone was 3.6 days. The mean postoperative stay for patients who underwent perforator ligation with concomitant stripping procedure was 5 days. INTERPRETATION AND CONCLUSION Majority of the patients present with complications of varicose vein with combined valvular incompetence and surgical treatment with stripping of path

  18. Path Integrals and Hamiltonians

    Science.gov (United States)

    Baaquie, Belal E.

    2014-03-01

    1. Synopsis; Part I. Fundamental Principles: 2. The mathematical structure of quantum mechanics; 3. Operators; 4. The Feynman path integral; 5. Hamiltonian mechanics; 6. Path integral quantization; Part II. Stochastic Processes: 7. Stochastic systems; Part III. Discrete Degrees of Freedom: 8. Ising model; 9. Ising model: magnetic field; 10. Fermions; Part IV. Quadratic Path Integrals: 11. Simple harmonic oscillators; 12. Gaussian path integrals; Part V. Action with Acceleration: 13. Acceleration Lagrangian; 14. Pseudo-Hermitian Euclidean Hamiltonian; 15. Non-Hermitian Hamiltonian: Jordan blocks; 16. The quartic potential: instantons; 17. Compact degrees of freedom; Index.

  19. Path Problems in Networks

    CERN Document Server

    Baras, John

    2010-01-01

    The algebraic path problem is a generalization of the shortest path problem in graphs. Various instances of this abstract problem have appeared in the literature, and similar solutions have been independently discovered and rediscovered. The repeated appearance of a problem is evidence of its relevance. This book aims to help current and future researchers add this powerful tool to their arsenal, so that they can easily identify and use it in their own work. Path problems in networks can be conceptually divided into two parts: A distillation of the extensive theory behind the algebraic path pr

  20. Intercellular adhesion molecule-1 expression in the hippocampal CA1 region of hyperlipidemic rats with chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Yingying Cheng; Ying Zhang; Hongmei Song; Jiachun Feng

    2012-01-01

    Chronic cerebral ischemia is a pathological process in many cerebrovascular diseases and it is induced by long-term hyperlipidemia, hypertension and diabetes mellitus. After being fed a high-fat diet for 4 weeks, rats were subjected to permanent occlusion of bilateral common carotid arteries to establish rat models of chronic cerebral ischemia with hyperlipidemia. Intercellular adhesion molecule-1 expression in rat hippocampal CA1 region was determined to better understand the mechanism underlying the effects of hyperlipidemia on chronic cerebral ischemia. Water maze test results showed that the cognitive function of rats with hyperlipidemia or chronic cerebral ischemia, particularly in rats with hyperlipidemia combined with chronic cerebral ischemia, gradually decreased between 1 and 4 months after occlusion of the bilateral common carotid arteries. This correlated with pathological changes in the hippocampal CA1 region as detected by hematoxylin-eosin staining. Immunohistochemical staining showed that intercellular adhesion molecule-1 expression in the hippocampal CA1 region was noticeably increased in rats with hyperlipidemia or chronic cerebral ischemia, in particular in rats with hyperlipidemia combined with chronic cerebral ischemia. These findings suggest that hyperlipidemia aggravates chronic cerebral ischemia-induced neurological damage and cognitive impairment in the rat hippocampal CA1 region, which may be mediated, at least in part, by up-regulated expression of intercellular adhesion molecule-1.

  1. Brief RU 38486 Treatment Normalizes the Effects of Chronic Stress on Calcium Currents in Rat Hippocampal CA1 Neurons.

    NARCIS (Netherlands)

    Karst, H.; Joëls, M.

    2007-01-01

    Chronic stress alters many properties in rat brain, like serotonin responsiveness and dendritic morphology. In the present study, we examined (i) whether unpredictable stress during 21 days affects calcium (Ca) currents of CA1 pyramidal neurons recorded on day 22; and (ii) if so, whether this change

  2. Expression of Bacillus thuringiensis cytolytic toxin (Cyt2Ca1) in citrus roots to control Diaprepes abbreviatus larvae

    Science.gov (United States)

    Diaprepes abbreviatus (L.) is an important pest of citrus in the USA. Currently, no effective management strategies of Diaprepes abbreviatus exist in citriculture. To protect citrus against Diaprepes abbreviatus a transgenic citrus rootstock expressing Bacillus thuringiensis Cyt2Ca1, an insect toxin...

  3. Optimal design for hetero-associative memory: hippocampal CA1 phase response curve and spike-timing-dependent plasticity.

    Directory of Open Access Journals (Sweden)

    Ryota Miyata

    Full Text Available Recently reported experimental findings suggest that the hippocampal CA1 network stores spatio-temporal spike patterns and retrieves temporally reversed and spread-out patterns. In this paper, we explore the idea that the properties of the neural interactions and the synaptic plasticity rule in the CA1 network enable it to function as a hetero-associative memory recalling such reversed and spread-out spike patterns. In line with Lengyel's speculation (Lengyel et al., 2005, we firstly derive optimally designed spike-timing-dependent plasticity (STDP rules that are matched to neural interactions formalized in terms of phase response curves (PRCs for performing the hetero-associative memory function. By maximizing object functions formulated in terms of mutual information for evaluating memory retrieval performance, we search for STDP window functions that are optimal for retrieval of normal and doubly spread-out patterns under the constraint that the PRCs are those of CA1 pyramidal neurons. The system, which can retrieve normal and doubly spread-out patterns, can also retrieve reversed patterns with the same quality. Finally, we demonstrate that purposely designed STDP window functions qualitatively conform to typical ones found in CA1 pyramidal neurons.

  4. ERK1/2 Activation Is Necessary for BDNF to Increase Dendritic Spine Density in Hippocampal CA1 Pyramidal Neurons

    Science.gov (United States)

    Alonso, Mariana; Medina, Jorge H.; Pozzo-Miller, Lucas

    2004-01-01

    Brain-derived neurotrophic factor (BDNF) is a potent modulator of synaptic transmission and plasticity in the CNS, acting both pre- and postsynaptically. We demonstrated recently that BDNF/TrkB signaling increases dendritic spine density in hippocampal CA1 pyramidal neurons. Here, we tested whether activation of the prominent ERK (MAPK) signaling…

  5. Fast gamma oscillations are generated intrinsically in CA1 without the involvement of fast-spiking basket cells.

    Science.gov (United States)

    Craig, Michael T; McBain, Chris J

    2015-02-25

    Information processing in neuronal networks relies on the precise synchronization of ensembles of neurons, coordinated by the diverse family of inhibitory interneurons. Cortical interneurons can be usefully parsed by embryonic origin, with the vast majority arising from either the caudal or medial ganglionic eminences (CGE and MGE). Here, we examine the activity of hippocampal interneurons during gamma oscillations in mouse CA1, using an in vitro model where brief epochs of rhythmic activity were evoked by local application of kainate. We found that this CA1 KA-evoked gamma oscillation was faster than that in CA3 and, crucially, did not appear to require the involvement of fast-spiking basket cells. In contrast to CA3, we also found that optogenetic inhibition of pyramidal cells in CA1 did not significantly affect the power of the oscillation, suggesting that excitation may not be essential for gamma genesis in this region. We found that MGE-derived interneurons were generally more active than CGE interneurons during CA1 gamma, although a group of CGE-derived interneurons, putative trilaminar cells, were strongly phase-locked with gamma oscillations and, together with MGE-derived axo-axonic and bistratified cells, provide attractive candidates for being the driver of this locally generated, predominantly interneuron-driven model of gamma oscillations.

  6. Closed head injury causes hyperexcitability in rat hippocampal CA1 but not in CA3 pyramidal cells.

    Science.gov (United States)

    Griesemer, Désirée; Mautes, Angelika M

    2007-12-01

    Traumatic brain injury frequently elicits epileptic seizures hours or days after the impact. The mechanisms on cellular level are poorly understood. Because posttraumatic epilepsy appears in many cases as a temporal-lobe epilepsy which originated the hippocampus, we studied trauma-induced hyperexcitability on the cellular level in this brain area. We used the model of closed head injury to analyse the electrophysiological changes in CA1 and CA3 pyramidal cells and in interneurones of the CA1 field, which is extremely sensitive to ischemia. We found that morphologically closed head injury (CHI) led to a gradual progressive, cell type specific time course in neuronal degeneration. To analyse electrophysiological impairment we measured resting membrane potential, recorded spontaneous action potentials and induced action potentials by current pulses at different times after CHI. We found a dramatic increase in the frequency of spontaneous action potentials of CA1 but not of CA3 pyramidal cells after CHI. This hyperexcitability was maximal at 2 h (4.5-fold higher than sham), was also observed at 24 h after CHI and disappeared after 3 days. We found that CA1 interneurones responded by a much weaker increase of AP frequency after CHI. We conclude that the strong hyperexcitability after CHI is cell-type specific and transient. The understanding of the complex neuronal interactions probably offers a promising possibility for pharmacological intervention to prevent posttraumatic epilepsy.

  7. DNA fragmentation follows delayed neuronal death in CA1 neurons exposed to transient global ischemia in the rat.

    Science.gov (United States)

    Petito, C K; Torres-Munoz, J; Roberts, B; Olarte, J P; Nowak, T S; Pulsinelli, W A

    1997-09-01

    Apoptosis is an active, gene-directed process of cell death in which early fragmentation of nuclear DNA precedes morphological changes in the nucleus and, later, in the cytoplasm. In ischemia, biochemical studies have detected oligonucleosomes of apoptosis whereas sequential morphological studies show changes consistent with necrosis rather than apoptosis. To resolve this apparent discrepancy, we subjected rats to 10 minutes of transient forebrain ischemia followed by 1 to 14 days of reperfusion. Parameters evaluated in the CA1 region of the hippocampus included morphology, in situ end labeling (ISEL) of fragmented DNA, and expression of p53. Neurons were indistinguishable from controls at postischemic day 1 but displayed cytoplasmic basophilia or focal condensations at day 2; some neurons were slightly swollen and a few appeared normal. In situ end labeling was absent. At days 3 and 5, approximately 40 to 60% of CA1 neurons had shrunken eosinophilic cytoplasm and pyknotic nuclei, but only half of these were ISEL. By day 14, many of the necrotic neurons had been removed by phagocytes; those remaining retained mild ISEL. Neither p53 protein nor mRNA were identified in control or postischemic brain by in situ hybridization with riboprobes or by northern blot analysis. These results show that DNA fragmentation occurs after the development of delayed neuronal death in CA1 neurons subjected to 10 minutes of global ischemia. They suggest that mechanisms other than apoptosis may mediate the irreversible changes in the CA1 neurons in this model.

  8. Cell-Type Specific Inactivation of Hippocampal CA1 Disrupts Location-Dependent Object Recognition in the Mouse

    Science.gov (United States)

    Haettig, Jakob; Sun, Yanjun; Wood, Marcelo A.; Xu, Xiangmin

    2013-01-01

    The allatostatin receptor (AlstR)/ligand inactivation system enables potent regulation of neuronal circuit activity. To examine how different cell types participate in memory formation, we have used this system through Cre-directed, cell-type specific expression in mouse hippocampal CA1 in vivo and examined functional effects of inactivation of…

  9. DOPING DEPENDENCE OF THE CHEMICAL-POTENTIAL IN BI2SR2CA1-XYXCU2O8+DELTA

    NARCIS (Netherlands)

    VANVEENENDAAL, MA; SCHLATMANN, R; SAWATZKY, GA; GROEN, WA

    1993-01-01

    A detailed study of the doping dependence of valence- and core-level spectra of Bi2Sr2Ca1-xYxCu2O8+delta leads to the conclusion that the chemical potential shifts in a manner consistent with that of a simple doped semiconductor. The spectroscopically observed filling in of the gap upon doping of th

  10. Clioquinol inhibits zinc-triggered caspase activation in the hippocampal CA1 region of a global ischemic gerbil model.

    Directory of Open Access Journals (Sweden)

    Tao Wang

    Full Text Available BACKGROUND: Excessive release of chelatable zinc from excitatory synaptic vesicles is involved in the pathogenesis of selective neuronal cell death following transient forebrain ischemia. The present study was designed to examine the neuroprotective effect of a membrane-permeable zinc chelator, clioquinol (CQ, in the CA1 region of the gerbil hippocampus after transient global ischemia. METHODOLOGY/PRINCIPAL FINDINGS: The common carotid arteries were occluded bilaterally, and CQ (10 mg/kg, i.p. was injected into gerbils once a day. The zinc chelating effect of CQ was examined with TSQ fluorescence and autometallography. Neuronal death, the expression levels of caspases and apoptosis inducing factor (AIF were evaluated using TUNEL, in situ hybridization and Western blotting, respectively. We were able to show for the first time that CQ treatment attenuates the ischemia-induced zinc accumulation in the CA1 pyramidal neurons, accompanied by less neuronal loss in the CA1 field of the hippocampus after ischemia. Furthermore, the expression levels of caspase-3, -9, and AIF were significantly decreased in the hippocampus of CQ-treated gerbils. CONCLUSIONS/SIGNIFICANCE: The present study indicates that the neuroprotective effect of CQ is related to downregulation of zinc-triggered caspase activation in the hippocampal CA1 region of gerbils with global ischemia.

  11. Proteasome alteration and delayed neuronal death in hippocampal CA1 and dentate gyrus regions following transient cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Pengfei Ge; Tianfei Luo; Jizhou Zhang; Haifeng Wang; Wenchen Li; Yongxin Luan; Feng Ling; Yi'nan Luo

    2009-01-01

    BACKGROUND:Proteasome dysfunction has been reported to induce abnormal protein aggregation and cell death.OBJECTIVE:To investigate the effect of proteasome changes on delayed neuronal death in CA1 and dentate gyrus (DG) regions of the rat hippocampus following transient cerebral ischemia.DESIGN,TIME AND SETTING:A randomized,controlled animal experiment.The study was performed at the Department of Biochemistry and Molecular Biology,Norman Bethune Medical College of Jilin University,from September 2006 to May 2008.MATERIALS:Rabbit anti-19S S10B polyclonal antibody was purchased from Bioreagents,USA;propidium iodide and fluorescently-labeled goat anti-rabbit IgG were purchased from Jackson Immunoresearch,USA;hematoxylin and eosin staining solution was purchased from Sigma,USA;LSM 510 confocal microscope was purchased from Zeiss,Germany.METHODS:A total of 40 healthy Wistar rats,male,4 months old,were randomly divided into sham surgery group (n=8) and model group (n=32).Ischemic models were established in the model group by transient clamping of the bilateral carotid arteries and decreased blood pressure.After 20 minutes of global ischemia,the clamp was removed to allow blood flow for 30 minutes,4,24,and 72 hours,respectively,with 8 rats at each time point.The bilateral carotid arteries were not ligated in the sham surgery group.MAIN OUTCOME MEASURES:Neuronal death in the CA1 and DG regions was observed by hematoxylin-eosin staining.Proteasome expression in CA1 and DG region neurons was detected by immunohistochemistry.RESULTS:Hematoxylin-eosin staining showed neuronal death in the CA1 region alone at 72 hours of reperfusion following ischemia.In comparison to the sham surgery group,a significant decrease in proteasome expression was observed,by immunohistochemistry,in the CA1 and DG regions in the model group,following 30 minutes,4,24,and 72 hours of reperfusion (P<0.01).After 72 hours of reperfusion following ischemia,proteasome expression had almost completely

  12. BDNF up-regulates TrkB protein and prevents the death of CA1 neurons following transient forebrain ischemia.

    Science.gov (United States)

    Ferrer, I; Ballabriga, J; Martí, E; Pérez, E; Alberch, J; Arenas, E

    1998-04-01

    The neurotrophin family of growth factors, which includes Nerve Growth Factor (NGF), Brain-Derived Neurotrophic Factor (BDNF), Neurotrophin-3 (NT3) and Neurotrophin-4/5 (NT4/5) bind and activate specific tyrosine kinase (Trk) receptors to promote cell survival and growth of different cell populations. For these reasons, growing attention has been paid to the use of neurotrophins as therapeutic agents in neurodegeneration, and to the regulation of the expression of their specific receptors by the ligands. BDNF expression, as revealed by immunohistochemistry, is found in the pre-subiculum, CA1, CA3, and dentate gyrus of the hippocampus. Strong TrkB immunoreactivity is present in most CA3 neurons but only in scattered neurons of the CA1 area. Weak TrkB immunoreactivity is found in the granule cell layer of the dentate gyrus. Unilateral grafting of BDNF-transfected fibroblasts into the hippocampus resulted in a marked increase in the intensity of the immunoreaction and in the number of TrkB-immunoreactive neurons in the granule cell layer of the dentate gyrus, pre-subiculum and CA1 area in the vicinity of the graft. No similar effects were produced after the injection of control mock-transfected fibroblasts. Delayed cell death in the CA1 area was produced following 5 min of forebrain ischemia in the gerbil. The majority of living cells in the CA1 area at the fourth day were BDNF/TrkB immunoreactive. Unilateral grafting of control mock-transfected or BDNF fibroblasts two days before ischemia resulted in a moderate non-specific protection of TrkB-negative, but not TrkB-positive cells, in the CA1 area of the grafted side. This finding is in line with a vascular and glial reaction, as revealed, by immunohistochemistry using astroglial and microglial cell markers. This astroglial response was higher in the grafted side than in the contralateral side in ischemic gerbils, but no differences were seen between BDNF-producing and non-BDNF-producing grafts. However, grafting of

  13. Multi-Dimensional Path Queries

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    1998-01-01

    We present the path-relationship model that supports multi-dimensional data modeling and querying. A path-relationship database is composed of sets of paths and sets of relationships. A path is a sequence of related elements (atoms, paths, and sets of paths). A relationship is a binary path...... to create nested path structures. We present an SQL-like query language that is based on path expressions and we show how to use it to express multi-dimensional path queries that are suited for advanced data analysis in decision support environments like data warehousing environments...

  14. Different patterns of amygdala priming differentially affect dentate gyrus plasticity and corticosterone, but not CA1 plasticity.

    Directory of Open Access Journals (Sweden)

    Rose-Marie eVouimba

    2013-05-01

    Full Text Available Stress-induced activation of the amygdala is involved in the modulation of memory processes in the hippocampus. However, stress effects on amygdala and memory remain complex. The activation of the basolateral amygdala (BLA was found to modulate plasticity in other brain areas, including the hippocampus. We previously demonstrated a differential effect of BLA priming on LTP in the CA1 and the dentate gyrus (DG. While BLA priming suppressed long term potentiation (LTP in CA1, it was found to enhance it in the DG. However, since the amygdala itself is amenable to experience-induced plasticity it is thus conceivable that when activity within the amygdala is modified this will have impact on the way the amygdala modulates activity and plasticity in other brain areas. In the current study we examined the effects of different patterns of BLA activation on the modulation of LTP in the DG and CA1, as well as on serum corticosterone (CORT. In CA1, BLA priming impaired LTP induction as was reported before. In contrast, in the DG, varying BLA stimulation intensity and frequency resulted in differential effects on LTP, ranging from no effect to strong impairment or enhancement. Varying BLA stimulation patterns resulted in also differential alterations in Serum CORT, leading to higher CORT levels being positively correlated with LTP magnitude in DG but not in CA1.The results support the notion of a differential role for the DG in aspects of memory, and add to this view the possibility that DG-associated aspects of memory will be enhanced under more emotional or stressful conditions. It is interesting to think of BLA patterns of activation and the differential levels of circulating CORT as two arms of the emotional and stress response that attempt to synchronize brain activity to best meet the challenge. It is foreseeable to think of abnormal such synchronization under extreme conditions, which would lead to the development of maladaptive behavior.

  15. Effect of ischemic preconditioning on antioxidant status in the gerbil hippocampal CA1 region after transient forebrain ischemia.

    Science.gov (United States)

    Park, Seung Min; Park, Chan Woo; Lee, Tae-Kyeong; Cho, Jeong Hwi; Park, Joon Ha; Lee, Jae-Chul; Chen, Bai Hui; Shin, Bich-Na; Ahn, Ji Hyeon; Tae, Hyun-Jin; Shin, Myoung Cheol; Ohk, Taek Geun; Cho, Jun Hwi; Won, Moo-Ho; Choi, Soo Young; Kim, In Hye

    2016-07-01

    Ischemic preconditioning (IPC) is a condition of sublethal transient global ischemia and exhibits neuroprotective effects against subsequent lethal ischemic insult. We, in this study, examined the neuroprotective effects of IPC and its effects on immunoreactive changes of antioxidant enzymes including superoxide dismutase (SOD) 1 and SOD2, catalase (CAT) and glutathione peroxidase (GPX) in the gerbil hippocampal CA1 region after transient forebrain ischemia. Pyramidal neurons of the stratum pyramidale (SP) in the hippocampal CA1 region of animals died 5 days after lethal transient ischemia without IPC (8.6% (ratio of remanent neurons) of the sham-operated group); however, IPC prevented the pyramidal neurons from subsequent lethal ischemic injury (92.3% (ratio of remanent neurons) of the sham-operated group). SOD1, SOD2, CAT and GPX immunoreactivities in the sham-operated animals were easily detected in pyramidal neurons in the stratum pyramidale (SP) of the hippocampal CA1 region, while all of these immunoreactivities were rarely detected in the stratum pyramidale at 5 days after lethal transient ischemia without IPC. Meanwhile, their immunoreactivities in the sham-operated animals with IPC were similar to (SOD1, SOD2 and CAT) or higher (GPX) than those in the sham-operated animals without IPC. Furthermore, their immunoreactivities in the stratum pyramidale of the ischemia-operated animals with IPC were steadily maintained after lethal ischemia/reperfusion. Results of western blot analysis for SOD1, SOD2, CAT and GPX were similar to immunohistochemical data. In conclusion, IPC maintained or increased the expression of antioxidant enzymes in the stratum pyramidale of the hippocampal CA1 region after subsequent lethal transient forebrain ischemia and IPC exhibited neuroprotective effects in the hippocampal CA1 region against transient forebrain ischemia.

  16. Modeling sharp wave-ripple complexes through a CA3-CA1 network model with chemical synapses.

    Science.gov (United States)

    Taxidis, Jiannis; Coombes, Stephen; Mason, Robert; Owen, Markus R

    2012-05-01

    The hippocampus, and particularly the CA3 and CA1 areas, exhibit a variety of oscillatory rhythms that span frequencies from the slow theta range (4-10 Hz) up to fast ripples (200 Hz). Various computational models of different complexities have been developed in an effort to simulate such population oscillations. Nevertheless the mechanism that underlies the so called Sharp Wave-Ripple complex (SPWR), observed in extracellular recordings in CA1, still remains elusive. We present here, the combination of two simple but realistic models of the rat CA3 and CA1 areas, connected together in a feedforward scheme mimicking Schaffer collaterals. Both network models are computationally simple one-dimensional arrays of excitatory and inhibitory populations interacting only via fast chemical synapses. Connectivity schemes and postsynaptic potentials are based on physiological data, yielding a realistic network topology. The CA3 model exhibits quasi-synchronous population bursts, which give rise to sharp wave-like deep depolarizations in the CA1 dendritic layer accompanied by transient field oscillations at ≈ 150-200 Hz in the somatic layer. The frequency and synchrony of these oscillations is based on interneuronal activity and fast-decaying recurrent inhibition in CA1. Pyramidal cell spikes are sparse and come from a subset of cells receiving stronger than average excitatory input from CA3. The model is shown to accurately reproduce a large number of basic characteristics of SPWRs and yields a new mechanism for the generation of ripples, offering an interpretation to a range of neurophysiological observations, such as the ripple disruption by halothane and the selective firing of pyramidal cells during ripples, which may have implications for memory consolidation during SPWRs.

  17. Electrophysiological effects of SKF83959 on hippocampal CA1 pyramidal neurons: potential mechanisms for the drug's neuroprotective effects.

    Directory of Open Access Journals (Sweden)

    Hong-Yuan Chu

    Full Text Available Although the potent anti-parkinsonian action of the atypical D₁-like receptor agonist SKF83959 has been attributed to the selective activation of phosphoinositol(PI-linked D₁ receptor, whereas the mechanism underlying its potent neuroprotective effect is not fully understood. In the present study, the actions of SKF83959 on neuronal membrane potential and neuronal excitability were investigated in CA1 pyramidal neurons of rat hippocampal slices. SKF83959 (10-100 µM caused a concentration-dependent depolarization, associated with a reduction of input resistance in CA1 pyramidal neurons. The depolarization was blocked neither by antagonists for D₁, D₂, 5-HT(2A/2C receptors and α₁-adrenoceptor, nor by intracellular dialysis of GDP-β-S. However, the specific HCN channel blocker ZD7288 (10 µM antagonized both the depolarization and reduction of input resistance caused by SKF83959. In voltage-clamp experiments, SKF83959 (10-100 µM caused a concentration-dependent increase of Ih current in CA1 pyramidal neurons, which was independent of D₁ receptor activation. Moreover, SKF83959 (50 µM caused a 6 mV positive shift in the activation curve of Ih and significantly accelerated the activation of Ih current. In addition, SKF83959 also reduced the neuronal excitability of CA1 pyramidal neurons, which was manifested by the decrease in the number and amplitude of action potentials evoked by depolarizing currents, and by the increase of firing threshold and rhoebase current. The above results suggest that SKF83959 increased Ih current through a D₁ receptor-independent mechanism, which led to the depolarization of hippocampal CA1 pyramidal neurons. These findings provide a novel mechanism for the drug's neuroprotective effects, which may contributes to its therapeutic benefits in Parkinson's disease.

  18. Repeated transcranial magnetic stimulation prevents kindling-induced changes in electrophysiological properties of rat hippocampal CA1 pyramidal neurons.

    Science.gov (United States)

    Shojaei, A; Semnanian, S; Janahmadi, M; Moradi-Chameh, H; Firoozabadi, S M; Mirnajafi-Zadeh, J

    2014-11-01

    The mechanisms underlying antiepileptic or antiepileptogenic effects of repeated transcranial magnetic stimulation (rTMS) are poorly understood. In this study, we investigated the effect of rTMS applied during rapid amygdala kindling on some electrophysiological properties of hippocampal CA1 pyramidal neurons. Male Wistar rats were kindled by daily electrical stimulation of the basolateral amygdala in a semi-rapid manner (12 stimulations/day) until they achieved stage-5 seizure. One group (kindled+rTMS (KrTMS)) of animals received rTMS (1Hz for 4min) 5min after termination of daily kindling stimulations. Twenty four hours following the last kindling stimulation electrophysiological properties of hippocampal CA1 pyramidal neurons were investigated using whole-cell patch-clamp technique. Amygdala kindling significantly depolarized the resting membrane potential and increased the input resistance, spontaneous firing activity, number of evoked spikes and half-width of the first evoked spike. Kindling also decreased the first-spike latency and amplitude significantly. Application of rTMS during kindling somehow prevented the development of seizures and protected CA1 pyramidal neurons of hippocampus against deleterious effect of kindling on both passive and active neuronal electrophysiological properties. Interestingly, application of rTMS alone enhanced the excitability of CA1 pyramidal neurons significantly. Based on the results of our study, it may be suggested that rTMS exerts its anticonvulsant effect, in part, through preventing the amygdala kindling-induced changes in electrophysiological properties of hippocampal CA1 pyramidal neurons. It seems that rTMS exerts protective effects on the neural circuits involved in spreading the seizures from the focus to other parts of the brain.

  19. Ketogenic diets cause opposing changes in synaptic morphology in CA1 hippocampus and dentate gyrus of late-adult rats.

    Science.gov (United States)

    Balietti, Marta; Giorgetti, Belinda; Fattoretti, Patrizia; Grossi, Yessica; Di Stefano, Giuseppina; Casoli, Tiziana; Platano, Daniela; Solazzi, Moreno; Orlando, Fiorenza; Aicardi, Giorgio; Bertoni-Freddari, Carlo

    2008-06-01

    Ketogenic diets (KDs) have beneficial effects on several diseases, such as epilepsy, mitochondriopathies, cancer, and neurodegeneration. However, little is known about their effects on aging individuals. In the present study, late-adult (19-month-old) rats were fed for 8 weeks with two medium chain triglycerides (MCT)-KDs, and the following morphologic parameters reflecting synaptic plasticity were evaluated in stratum moleculare of hippocampal CA1 region (SM CA1) and outer molecular layer of hippocampal dentate gyrus (OML DG): average area (S), numeric density (Nv(s)), and surface density (Sv) of synapses, and average volume (V), numeric density (Nv(m)), and volume density (Vv) of synaptic mitochondria. In SM CA1, MCT-KDs induced the early appearance of the morphologic patterns typical of old animals (higher S and V, and lower Nv(s) and Nv(m)). On the contrary, in OML DG, Sv and Vv of MCT-KDs-fed rats were higher (as a result of higher Nv(s) and Nv(m)) versus controls; these modifications are known to improve synaptic function and metabolic supply. The opposite effects of MCT-KDs might reflect the different susceptibility to aging processes: OML DG is less vulnerable than SM CA1, and the reactivation of ketone bodies uptake and catabolism might occur more efficiently in this region, allowing the exploitation of their peculiar metabolic properties. Present findings provide the first evidence that MCT-KDs may cause opposite morphologic modifications, being potentially harmful for SM CA1 and potentially advantageous for OML DG. This implies risks but also promising potentialities for their therapeutic use during aging.

  20. CORRELATION BETWEEN TYMPANIC MEMBRANE PERFORATION AND HEARING LOSS

    Directory of Open Access Journals (Sweden)

    Lidija RISTOVSKA

    2016-04-01

    Full Text Available Introduction: Perforation of the tympanic membrane primarily results from middle ear infections, trauma or iatrogenic causes. The perforation causes conductive hearing loss by reducing the surface area available for sound transmission to the ossicular chain. Objective: The objective was to analyze the characteristics of tympanic membrane perforations in relation to hearing loss and to determine the type and degree of hearing loss. Materials and methods: We analyzed audiometric, otoscopic findings and medical reports of 218 patients, 114 males (52.3% and 104 females (47.7%, aged 9 to 75 years (mean age of 47.9 years, examined during the period of November 2012 to October 2015. For statistical data analysis we used Chi-square test with level of significance p<0.05. Results: Most of the patients had unilateral perforations (89% with right ear predominance and involvement of two quadrants of pars tensa (37.2%. Mean air-bone gap was 23.9 dB. The largest air-bone gap was at frequency of 250 Hz. Most of the patients (73.1% had mixed hearing loss (p=0.032, and average hearing thresholds from 21 to 40 dB. Conclusion: Mean air-bone gap is largest at the lower frequencies, and decreases as frequency increases. Size of the perforation has effect on hearing loss. Mean air-bone gap increases with increasing size of the perforation. There is no big difference between the mean air-bone gap in posterior versus anterior perforations.

  1. COMPARATIVE STUDY OF LAPAROSCOPIC CLOSURE OPEN PEPTIC PERFORATION CLOSURE

    Directory of Open Access Journals (Sweden)

    Vivek

    2015-10-01

    Full Text Available Laparoscopic closure of perforated duodenal ulcer was first performed in the year 1990 . Due to its advantage of better view of the peritoneal cavity an opportunity for thorough lavage and avoidance of upper abdominal incision, with its related complication, especially in high – ri sk patients, this procedure has gained popularity all over the world. Approximately 10 - 20% of patients suffering from peptic ulcer develop perforation of stomach or duodenum in which, chemical peritonitis develop initially from gastric secretion and duoden al secretion the condition is life threatening. Early diagnosis and treatment is extremely important. Mortality will increase up if perforation exists more than 24 to 48 hours. Usually surgical intervention of simple closure with omental patch of the perforation is required. this study aims at evaluating efficacy , safety and outcome of laparoscopic surgery for perforated duodenal ulcer patients admitted during period Jan 2009 to Dec 2012 at tertiary hospital in north Karnataka A total of 61cases diagnosed as peritonitis secondary to duodenal ulcer perforation were involved in the study 30underwent open perforation closure and 31 cases underwent lap closure. Peptic ulcers are focal defects in the gastric or duodenal mucosa which extend into the sub mucosa or deeper. they may be acute or chronic and ultimately are caused by on imbalance between the action of peptic acid and mucosal defenses peptic ulcer remains a common outpatient diagnosis, but the number of elective operations for peptic ul cer disease have decreased dramatically over the past 30 decades due to the advent of H2 blockers However the incidence of emergency surgeries, and death rate associated with peptic ulcer are same

  2. Chromium geochemistry of the ca. 1.85 Ga Flin Flon paleosol.

    Science.gov (United States)

    Babechuk, M G; Kleinhanns, I C; Schoenberg, R

    2017-01-01

    Fractionation of stable Cr isotopes has been measured in Archaean paleosols and marine sedimentary rocks and interpreted to record the terrestrial oxidation of Cr(III) to Cr(VI), providing possible indirect evidence for the emergence of oxygenic photosynthesis. However, these fractionations occur amidst evidence from other geochemical proxies for a pervasively anoxic atmosphere. This study examined the Cr geochemistry of the ca. 1.85 Ga Flin Flon paleosol, which developed under an atmosphere unambiguously oxidising enough to quantitatively convert Fe(II) to Fe(III) during pedogenesis. The paleosol shows an extreme range in Cr isotope composition of 2.76 ‰ δ(53/52) Cr. The protolith greenstone (δ(53/52) Cr: -0.23 ‰), the deepest weathering horizon (δ(53/52) Cr: -0.15 to -0.23 ‰) and a residual corestone in the upper paleosol (δ(53/52) Cr: -0.01 ‰) all exhibit Cr isotopic compositions comparable to unaltered igneous rocks. The most significant isotopic fractionation is preserved in the areas influenced by oxidative subaerial weathering (i.e. increase in Fe(III)/Fe(II)) and the greatest loss of mobile elements. The uppermost paleosol horizon is both Cr and Mn depleted and offset to significantly (53) Cr-enriched compositions (δ(53/52) Cr values between +1.50 and +2.38 ‰), which is not easily modelled with the oxidation of Cr(III) and loss of isotopically heavy Cr(VI). Instead, the currently preferred model for these data invokes the open-system removal of isotopically light aqueous Cr(III) during either pedogenesis or subsequent hydrothermal/metamorphic alteration. The (53) Cr enrichment would then represent the preferential dissolution or complexation of isotopically light aqueous Cr(III) species (enhanced by lower pH conditions and possibly the presence of complexing ligands) and/or the residual signature from preferential adsorption of isotopically heavy Cr(III). Both scenarios would contradict the widely held assumption that only redox reactions of

  3. P53、Noxa在血管性痴呆大鼠海马CA1区中表达及意义%Expression of P53 and Noxa in hippocampal CA1. area of rats with vascular dementia

    Institute of Scientific and Technical Information of China (English)

    朱燕珍; 林凌

    2008-01-01

    目的 观测P53、Noxa在血管性痴呆大鼠海马CA1区表达,探讨血管性痴呆的发病机制.方法 经Morris水迷宫筛选出学习记忆能力处于正常值范围的雄性SD大鼠24只,随机分为假手术组和模型组(各12只),采用双侧颈总动脉结扎法制备血管性痴呆大鼠模型,手术后2个月用Morris水迷宫观测各组大鼠在空间学习记忆方面的变化,HE染色观察各组大鼠海马CA1区锥体细胞形态学变化,免疫荧光染色检测P53、Noxa在海马CA1区锥体细胞的表达.结果 模型组大鼠相对假手术组大鼠平均逃避潜伏期延长(P<0.01),空间记忆能力减退(P<0.01),海马CA1区神经细胞凋亡明显,P53、Noxa在海马CA1区表达的阳性细胞数明显升高(P<0.05),且直线相关分析显示Noxa的表达与P53的表达呈正相关(P<0.01).结论 海马CA1区P53和Noxa的表达升高在血管性痴呆发病机制中起重要作用.

  4. Bladder perforation in a peritoneal dialysis patient

    Directory of Open Access Journals (Sweden)

    M Ounissi

    2012-01-01

    Full Text Available The dysfunction of the catheter in peritoneal dialysis (PD is a frequent compli-cation. However, perforation of organs are rare, particularly that of the urinary bladder. This re-quires an early diagnosis and prompt treatment of patients. We report here the case of a 38-year-old woman having end-stage renal disease due to autosomal-dominant polycystic kidney disease treated by PD since November 2000. Three years later, she was treated for Staphylococcal peritonitis. Four months later, she presented with a severe urge to urinate at the time of the fluid exchanges. The biochemical analysis of the fluid from the bladder showed that it was dialysis fluid. Injection of contrast through the catheter demonstrated the presence of a fistula between the bladder and the peritoneal cavity. She underwent cystoscopic closure of the fistulous tract and the PD catheter was removed. Subsequently, the patient was treated by hemodialysis. One month later, a second catheter was implanted surgically after confirming the closure of the fistula. Ten days later, she presented with pain at the catheter site and along the tunnel, which was found to be swollen along its track. The injection of contrast produced swelling of the subcutaneous tunnel but without extravasation of the dye. PD was withdrawn and the patient was put back on hemodialysis. Bladder fistula is a rare complication in PD and diagnosis should be suspected when patient complains of an urge to pass urine during the exchanges, which can be confirmed by contrast study showing presence of dye in the bladder. PD may be possible after the closure of the fistula, but recurrence may occur.

  5. Jet Screech Reduction with Perforated Flat Reflector

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In the present experimental study, investigations have been carried out to evaluate the performance of the new control technique of jet screech with different perforated flat reflectors. Mainly two types of porous flat reflectors had been used in the experiment. One reflector (reflector-V) designed for placing the reflector surface vertical to the jet axis, when, another type of reflector (reflector-H) designed for placing the reflecting surface horizontal to the jet axis. In both cases the reflectors had been placed at the nozzle (base tube with uniform cross-sectional area)exit. The diameter of the reflector-V was 15D when the diameter of the reflector-H was 10D. The porous area of the reflector-V was 6D and 4.5D for reflector-H where D indicated the diameter of the nozzle exit. The placement of the reflector at the exit of the nozzle reduces the sound pressure at the nozzle exit. Thus the muted sound can not excite the unstable disturbance at the nozzle exit and the loop of the feedback mechanism disappeared, finally,the generation of jet screech be cancelled. The suction space located at the back side of the porous surface of the reflector-V improves the efficiency of the screech control technique. However, in the case of reflector-H, the receptivity process of feedback loop had been controlled by reducing the disturbances at the effective shock fronts as well as at the nozzle exit. The performance of the proposed method was verified with a flat reflector concept and good performance in jet screech suppression has been confirmed in the case of porous reflector.

  6. Does Ramadan Fasting Increase duodenal ulcer perforation?

    Directory of Open Access Journals (Sweden)

    Abdoulhossein Davoodabadi

    2016-03-01

    Full Text Available Introduction: In Ramadan, healthy adult Muslims are obliged to fast. Prolonged fasting increase gastric acid and pepsin levels, which promote the risk of duodenal ulcer perforation (DUP. Effects of Ramadan fasting on DUP have not been thoroughly studied yet, and the limited number of studies investigating the impact of Ramadan fasting on DUP yielded discrepant results. This study aimed to evaluate DUP frequency during Ramadan 2011-2015 and compare it with other months. Methods: This cross-sectional study was performed in 82 patients undergoing surgery due to DUP during July 2011-September 2015. The demographics, history of addiction, use of nonsteroidal and antiinflammatory drugs, previous history of acid peptic disease, as well as complications and outcomes of treatment were recorded and analyzed, and the obtained results were compared between Ramadan and other lunar months. Results: The majority of patients were male (86.6%, 71 patients, with a mean age of 43.9±16.5 years (age range: 20-75 years. Male to female ratio was 6:1. Cases with less than 30 years of age were less frequent (22%, 18 patients. DUP was more frequent during Rajab with nine cases (11%, while during Ramadan, six cases were reported, the difference between Ramadan and other months regarding the incidence of DUP was not significant (P=0.7. Risk factors such as smoking (60% and addiction (44%; especially to crystal and crack were noted. Consumption of nonsteroidal antiinflammatory drugs in 20 (24% patients, and use of antacids in 17 (25% patients. Distribution of DUP in different blood types was as follows: O+=41%, A+=28%, B+=23%, AB=5%, and O-=3%; moreover, post-operative Helicobacter pylori antibody was present in 67% of the patients. Conclusion: Ramadan fasting did not escalate DUP incidence, and those with DUP risk factors can fast with the use of antacids.

  7. Jet screech reduction with perforated flat reflector

    Science.gov (United States)

    Khan, Md. Tawhidul Islam; Teramoto, Kenbu; Matsuo, Shigeru; Setoguchi, Toshiaki

    2008-09-01

    In the present experimental study, investigations have been carried out to evaluate the performance of the new control technique of jet screech with different perforated flat reflectors. Mainly two types of porous flat reflectors had been used in the experiment. One reflector (reflector-V) designed for placing the reflector surface vertical to the jet axis, when, another type of reflector (reflector-H) designed for placing the reflecting surface horizontal to the jet axis. In both cases the reflectors had been placed at the nozzle (base tube with uniform cross-sectional area) exit. The diameter of the reflector-V was 15D when the diameter of the reflector-H was 10D. The porous area of the reflector-V was 6D and 4.5D for reflector-H where D indicated the diameter of the nozzle exit. The placement of the reflector at the exit of the nozzle reduces the sound pressure at the nozzle exit. Thus the muted sound can not excite the unstable disturbance at the nozzle exit and the loop of the feedback mechanism disappeared, finally, the generation of jet screech be cancelled. The suction space located at the back side of the porous surface of the reflector-V improves the efficiency of the screech control technique. However, in the case of reflector-H, the receptivity process of feedback loop had been controlled by reducing the disturbances at the effective shock fronts as well as at the nozzle exit. The performance of the proposed method was verified with a flat reflector concept and good performance in jet screech suppression has been confirmed in the case of porous reflector.

  8. Path dependence and creation

    DEFF Research Database (Denmark)

    Garud, Raghu; Karnøe, Peter

    the place of agency in these theories that take history so seriously. In the end, they are as interested in path creation and destruction as they are in path dependence. This book is compiled of both theoretical and empirical writing. It shows relatively well-known industries such as the automobile...

  9. Unique Path Partitions

    DEFF Research Database (Denmark)

    Bessenrodt, Christine; Olsson, Jørn Børling; Sellers, James A.

    2013-01-01

    We give a complete classification of the unique path partitions and study congruence properties of the function which enumerates such partitions.......We give a complete classification of the unique path partitions and study congruence properties of the function which enumerates such partitions....

  10. A CLINICAL STUDY ON PATIENTS WITH DUODENAL ULCER PERFORATION

    Directory of Open Access Journals (Sweden)

    Kishore Babu

    2016-03-01

    Full Text Available INTRODUCTION Perforated duodenal ulcer, the most catastrophic complication was Associated with high mortality in the past due to late presentation of the patients, delay in surgery and lack of antibiotics. Various authors state that the incidence of peptic ulcer disease and perforation has been declining for the past 3 decades. Because of advances in the medical therapy of peptic ulcer with a wide range of drugs the management of peptic ulcer disease has been changing and the role of surgery has been declining. Perforation is usually seen in 3rd and 4th decades with a male preponderance and the epidemiological trend is not the same worldwide. Incidence is slightly declining in western countries. The present study has been done during the period between 2013 and 2014 in S. V. R. R. Government general hospital Tirupati. AIMS AND OBJECTIVES The aim of the present study is to analyze the probable factors for increase in incidence of duodenal ulcer perforation, with particular emphasis on assessment of impact of H2 receptor antagonists and Proton Pump inhibitors on the incidence of perforation. STUDY SETTING S. V. Medical College, Department of General Surgery, Tirupati. STUDY PERIOD Patients attending S. V. Medical College, Department of General Surgery with perforation during the period from November 2013 to October 2014. INCLUSION CRITERIA Patients between age group of more than 14 years presenting with pain abdomen and who are diagnosed to have peritonitis due to duodenal ulcer perforation. EXCLUSION CRITERIA Patients with peritonitis due causes other than duodenal ulcer. STUDY METHOD Prospective Observational study among the selected patients. Total numbers of peptic ulcer cases that were admitted in this hospital and treated either medically or surgically were noted. The details of their clinical history and findings, investigation reports, operative findings, post-operative complications were recorded. Simple closure was performed for all the

  11. Free path groupoid grading on Leavitt path algebras

    OpenAIRE

    Goncalves, Daniel; Yoneda, Gabriela

    2015-01-01

    In this work we realize Leavitt path algebras as partial skew groupoid rings. This yields a free path groupoid grading on Leavitt path algebras. Using this grading we characterize free path groupoid graded isomorphisms of Leavitt path algebras that preserves generators.

  12. Reactive changes in astrocytes, and delayed neuronal death, in the rat hippocampal CA1 region following cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Guiqing Zhang; Xiang Luo; Zhiyuan Yu; Chao Ma; Shabei Xu; Wei Wang

    2009-01-01

    BACKGROUND: Blood supply to the hippocampus is not provided by the middle cerebral artery. However, previous studies have shown that delayed neuronal death in the hippocampus may occur following focal cerebral ischemia induced by middle cerebral artery occlusion. OBJECTIVE: To observe the relationship between reactive changes in hippocampal astrocytes and delayed neuronal death in the hippocampal CA1 region following middle cerebral artery occlusion. DESIGN, TIME AND SETTING: The immunohistochemical, randomized, controlled animal study was performed at the Laboratory of Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, from July to November 2007. MATERIALS: Rabbit anti-glial fibrillary acidic protein (GFAP) (Neomarkers, USA), goat anti-rabbit IgG (Sigma, USA) and ApoAlert apoptosis detection kit (Biosciences Clontech, USA) were used in this study. METHODS: A total of 42 healthy adult male Wistar rats, aged 3-5 months, were randomly divided into a sham operation group (n = 6) and a cerebral ischemia/reperfusion group (n = 36). In the cerebral ischemia/reperfusion group, cerebral ischemia/reperfusion models were created by middle cerebral artery occlusion. In the sham operation group, the thread was only inserted into the initial region of the internal carotid artery, and middle cerebral artery occlusion was not induced. Rats in the cerebral ischemia/reperfusion group were assigned to a delayed neuronal death (+) subgroup and a delayed neuronal death (-) subgroup, according to the occurrence of delayed neuronal death in the ischemic side of the hippocampal CA1 region following cerebral ischemia. MAIN OUTCOME MEASURES: Delayed neuronal death in the hippocampal CA1 region was measured by Nissl staining. GFAP expression and delayed neuronal death changes were measured in the rat hippocampal CA1 region at the ischemic hemisphere by double staining for GFAP and TUNEL. RESULTS: After 3 days of ischemia

  13. The research progress of acute small bowel perforation

    Institute of Scientific and Technical Information of China (English)

    Rudolf Schiessel

    2015-01-01

    This article reviews the various aetiologies of small bowel perforations and their management. In addition to the well-known aetiologies such as trauma, inflammation and circulatory disorders, several new causes of small bowel perforation have been described in recent years. The spectrum reaches from iatrogenic perforations during laparoscopic surgery or enteroscopies to drug-induced perforations with new anticancer agents. The management of small bowel perforations requires a concept consisting of the safe revision of the leaking bowel and the treatment of the peritonitis. Depending on the local situation and the condition of the patient, several treatment options are available. The surgical management of the bowel leak can range from a simple primary closure to a delayed restoration of bowel continuity. When the condition of the bowel or patient is frail, the risk of a failure of a closure or anastomosis is too high, and the exteriorization of the bowel defect as a primary measure is a safe option. The treatment of the peritonitis is also dependent on the condition of the patient and the local situation. Early stages of peritonitis can be treated by a simple peritoneal lavage, either performed by laparoscopy or laparotomy. Severe forms of peritonitis with multiorgan failure and an abdominal compartment syndrome need repeated peritoneal revisions. In such cases, the abdomen can only be closed temporarily. Different technical options are available in order to overcome the difficult care of these patients.

  14. Serrated needle design facilitates precise round window membrane perforation.

    Science.gov (United States)

    Stevens, James P; Watanabe, Hirobumi; Kysar, Jeffrey W; Lalwani, Anil K

    2016-07-01

    The round window membrane (RWM) has become the preferred route, over cochleostomy, for the introduction of cochlear implant electrodes as it minimizes inner ear trauma. However, in the absence of a tool designed for creating precise perforation, current practices lead to tearing of the RWM and significant intracochlear pressure fluctuations. On the basis of RWM mechanical properties, we have designed a multi-serrated needle to create consistent holes without membrane tearing or damaging inner ear structures. Four and eight-serrated needles were designed and produced with wire electrical discharge machining (EDM). The needle's ability to create RWM perforations was tested in deidentified, commercially acquired temporal bones with the assistance of a micromanipulator. Subsequently, specimens were imaged under light and scanning electron microscopy (SEM). The needles created consistent, appropriately sized holes in the membrane with minimal tearing. While a four-serrated crown needle made rectangular/trapezoid perforations, the octagonal crown formed smooth oval holes within the membrane. Though designed for single use, the needle tolerated repeated use without significant damage. The serrated needles formed precise perforations in the RWM while minimizing damage during cochlear implantation. The octagonal needle design created the preferred oval perforation better than the quad needle. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1633-1637, 2016.

  15. Perforated duodenal ulcer: A rare complication of deferasirox in children

    Science.gov (United States)

    Yadav, Sunil Kumar; Gupta, Vipul; El Kohly, Ashraf; Al Fadhli, Wasmi

    2013-01-01

    Duodenal ulcer perforation in pediatric age group is an uncommon entity; hence, it is not usually considered in the differential diagnosis of acute abdomen in these patients. It is important for the emergency physician to consider perforated peptic ulcer in the differential diagnosis of children presenting with acute abdominal pain, gastrointestinal bleeding, or shock. We report a 6½-year-old male child with thalassemia major who presented to emergency room with an acute abdomen and shock, who was subsequently found to have a perforated duodenal ulcer, probably related to use of oral chelating agent, deferasirox. Although, gastrointestinal symptoms like nausea, vomiting, and abdominal pain has been mentioned as infrequent adverse event in the scientific product information of deferasirox, in our current knowledge this is the first case report of perforated duodenal ulcer after oral deferasirox. The severity of this event justifies the reporting of this case. This patient had an atypical presentation in that there were no signs or symptoms of peptic ulcer disease before perforation and shock he was successfully managed with open surgery after initial resuscitation and stabilization of his general condition. PMID:23833377

  16. Coagulation syndrome: Delayed perforation after colorectal endoscopic treatments

    Institute of Scientific and Technical Information of China (English)

    Kingo; Hirasawa; Chiko; Sato; Makomo; Makazu; Hiroaki; Kaneko; Ryosuke; Kobayashi; Atsushi; Kokawa; Shin; Maeda

    2015-01-01

    Various procedure-related adverse events related to colonoscopic treatment have been reported. Previous studies on the complications of colonoscopic treatment have focused primarily on perforation or bleeding. Coagulation syndrome(CS), which is synonymous with transmural burn syndrome following endoscopic treatment, is another typical adverse event. CS is the result of electrocoagulation injury to the bowel wall that induces a transmural burn and localized peritonitis resulting in serosal inflammation. CS occurs after polypectomy, endoscopic mucosal resection(EMR), and even endoscopic submucosal dissection(ESD). The occurrence of CS after polypectomy or EMR varies according previous reports; most report an occurrence rate around 1%. However, artificial ulcers after ESD are largely theoretical, and CS following ESD was reported in about 9% of cases, which is higher than that for CS after polypectomy or EMR. Most cases of post-polypectomy syndrome(PPS) have an excellent prognosis, and they are managed conservatively with medical therapy. PPS rarely develops into delayed perforation. Delayed perforation is a severe adverse event that often requires emergency surgery. Since few studies have reported on CS and delayed perforation associated with CS, we focused on CS after colonoscopic treatments in this review. Clinicians should consider delayed perforation in CS patients.

  17. Perforated duodenal ulcer: a rare complication of deferasirox in children.

    Science.gov (United States)

    Yadav, Sunil Kumar; Gupta, Vipul; El Kohly, Ashraf; Al Fadhli, Wasmi

    2013-01-01

    Duodenal ulcer perforation in pediatric age group is an uncommon entity; hence, it is not usually considered in the differential diagnosis of acute abdomen in these patients. It is important for the emergency physician to consider perforated peptic ulcer in the differential diagnosis of children presenting with acute abdominal pain, gastrointestinal bleeding, or shock. We report a 6½-year-old male child with thalassemia major who presented to emergency room with an acute abdomen and shock, who was subsequently found to have a perforated duodenal ulcer, probably related to use of oral chelating agent, deferasirox. Although, gastrointestinal symptoms like nausea, vomiting, and abdominal pain has been mentioned as infrequent adverse event in the scientific product information of deferasirox, in our current knowledge this is the first case report of perforated duodenal ulcer after oral deferasirox. The severity of this event justifies the reporting of this case. This patient had an atypical presentation in that there were no signs or symptoms of peptic ulcer disease before perforation and shock he was successfully managed with open surgery after initial resuscitation and stabilization of his general condition.

  18. The research progress of acute small bowel perforation

    Directory of Open Access Journals (Sweden)

    Rudolf Schiessel

    2015-08-01

    Full Text Available This article reviews the various aetiologies of small bowel perforations and their management. In addition to the well-known aetiologies such as trauma, inflammation and circulatory disorders, several new causes of small bowel perforation have been described in recent years. The spectrum reaches from iatrogenic perforations during laparoscopic surgery or enteroscopies to drug-induced perforations with new anticancer agents. The management of small bowel perforations requires a concept consisting of the safe revision of the leaking bowel and the treatment of the peritonitis. Depending on the local situation and the condition of the patient, several treatment options are available. The surgical management of the bowel leak can range from a simple primary closure to a delayed restoration of bowel continuity. When the condition of the bowel or patient is frail, the risk of a failure of a closure or anastomosis is too high, and the exteriorization of the bowel defect as a primary measure is a safe option. The treatment of the peritonitis is also dependent on the condition of the patient and the local situation. Early stages of peritonitis can be treated by a simple peritoneal lavage, either performed by laparoscopy or laparotomy. Severe forms of peritonitis with multi-organ failure and an abdominal compartment syndrome need repeated peritoneal revisions. In such cases, the abdomen can only be closed temporarily. Different technical options are available in order to overcome the difficult care of these patients.

  19. Perforated duodenal ulcer: A rare complication of deferasirox in children

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Yadav

    2013-01-01

    Full Text Available Duodenal ulcer perforation in pediatric age group is an uncommon entity; hence, it is not usually considered in the differential diagnosis of acute abdomen in these patients. It is important for the emergency physician to consider perforated peptic ulcer in the differential diagnosis of children presenting with acute abdominal pain, gastrointestinal bleeding, or shock. We report a 6½-year-old male child with thalassemia major who presented to emergency room with an acute abdomen and shock, who was subsequently found to have a perforated duodenal ulcer, probably related to use of oral chelating agent, deferasirox. Although, gastrointestinal symptoms like nausea, vomiting, and abdominal pain has been mentioned as infrequent adverse event in the scientific product information of deferasirox, in our current knowledge this is the first case report of perforated duodenal ulcer after oral deferasirox. The severity of this event justifies the reporting of this case. This patient had an atypical presentation in that there were no signs or symptoms of peptic ulcer disease before perforation and shock he was successfully managed with open surgery after initial resuscitation and stabilization of his general condition.

  20. Displacements and stresses in bending of circular perforated plate

    Science.gov (United States)

    Atanasiu, C.; Sorohan, St.

    2016-08-01

    The flat plates, perforated by a large number of holes are widely used in the engineering, especially in the component of the process equipment. Strength calculations and experimental methods used in the actual literature for study perforated plates, do not present the problem in all its complexity for stress distribution and displacements. Research and doctoral theses in last decades, with methods characteristic of the respective periods were engaged either perforated plates considered infinite and requested the median plane or rarely, plate loaded normal to the median plane, with a small number of holes. In this work the stress distribution and displacement is presented for a circular plate perforated by 96 holes arranged in a grid of squares, simply supported on the outline and loaded through a central concentrated force or by uniformly distributed load. It conducted a numerical analysis by finite element method (FEM) with a proper meshing of the plate and an experimental study by holographic interferometry. Holographic interferometry method permits to measure, with high accuracy, extremely small displacements and comparing the results with those obtained by FEM becomes sustainable. Supplementary, an analysis of a non-perforated plate with the same dimensions and stiffness, similar loaded, was performed, determining the coefficient of stress concentration for a particular arrangement of holes.

  1. GABAA receptor-mediated feedforward and feedback inhibition differentially modulate the gain and the neural code transformation in hippocampal CA1 pyramidal cells.

    Science.gov (United States)

    Jang, Hyun Jae; Park, Kyerl; Lee, Jaedong; Kim, Hyuncheol; Han, Kyu Hun; Kwag, Jeehyun

    2015-12-01

    Diverse variety of hippocampal interneurons exists in the CA1 area, which provides either feedforward (FF) or feedback (FB) inhibition to CA1 pyramidal cell (PC). However, how the two different inhibitory network architectures modulate the computational mode of CA1 PC is unknown. By investigating the CA3 PC rate-driven input-output function of CA1 PC using in vitro electrophysiology, in vitro-simulation of inhibitory network, and in silico computational modeling, we demonstrated for the first time that GABAA receptor-mediated FF and FB inhibition differentially modulate the gain, the spike precision, the neural code transformation and the information capacity of CA1 PC. Recruitment of FF inhibition buffered the CA1 PC spikes to theta-frequency regardless of the input frequency, abolishing the gain and making CA1 PC insensitive to its inputs. Instead, temporal variability of the CA1 PC spikes was increased, promoting the rate-to-temporal code transformation to enhance the information capacity of CA1 PC. In contrast, the recruitment of FB inhibition sub-linearly transformed the input rate to spike output rate with high gain and low spike temporal variability, promoting the rate-to-rate code transformation. These results suggest that GABAA receptor-mediated FF and FB inhibitory circuits could serve as network mechanisms for differentially modulating the gain of CA1 PC, allowing CA1 PC to switch between different computational modes using rate and temporal codes ad hoc. Such switch will allow CA1 PC to efficiently respond to spatio-temporally dynamic inputs and expand its computational capacity during different behavioral and neuromodulatory states in vivo.

  2. THE ALTERATION OF NFP IN CA1 OF HIPPOCAMPUB IN MORPHINE DEPENDENT RATS%吗啡依赖性大鼠海马CA1区NPY细胞免疫组织化学研究

    Institute of Scientific and Technical Information of China (English)

    周郦楠; 张晖

    2004-01-01

    目的:观察吗啡依赖性大鼠海马区NPY细胞的变化.方法:用皮下注射吗啡法建立雄性大鼠吗啡依赖模型.用免疫组织化学和图像分析方法观察大鼠CA1区NPY细胞的变化.结果:吗啡依赖性大鼠海马CA1区NPY细胞免疫反应减弱(p<0.01).结论:NPY细胞减少与吗啡依赖性的发生、发展.

  3. 吗啡依赖性大鼠海马CA1区NPY细胞阳性表达%The Alteration of Npy in CA1 of Hippocampus in Morphine Dependent Rats

    Institute of Scientific and Technical Information of China (English)

    周郦楠; 张晖; 张晔; 张维; 刘永林

    2006-01-01

    目的 观察吗啡依赖性大鼠海马区NPY细胞的变化.方法 用皮下注射吗啡法建立雄性大鼠吗啡依赖模型.用免疫组织化学和图像分析方法观察大鼠CA1区NPY细胞的变化.结果 吗啡依赖性大鼠海马CA1区NPY细胞免疫反应减弱(p<0.01).结论 NPY细胞减少与吗啡依赖性的发生、发展.

  4. 吗啡依赖性大鼠海马CA1区AChE阳性反应物的变化%The alteration of AChE in CA1 of hippocampus in morphine dependent rats

    Institute of Scientific and Technical Information of China (English)

    周郦楠; 王辛荑; 张广新; 李开明

    2004-01-01

    目的:观察吗啡依赖性大鼠海马区AChE阳性反应物的变化.方法:用皮下注射吗啡法建立雄性大鼠吗啡依赖模型.用酶组织化学和图像分析方法观察大鼠CA1区AChE细胞的变化.结果:吗啡依赖性大鼠海马CA1区AChE细胞免疫反应减弱(P<0.01).结论:AChE阳性反应物减少与吗啡依赖性的发生、发展.

  5. Effect of microinjection of morphine into CA1 region of hippocampus on sleep of rats%海马CA1区注射吗啡对大鼠睡眠的影响

    Institute of Scientific and Technical Information of China (English)

    张瑾; 李春华; 汪凯; 王烈成; 章功良; 赵乐章; 张景行

    2010-01-01

    目的 观察吗啡在海马CA1区对大鼠睡眠的影响.方法 选择雄性成年SD大鼠39只,分为对照组(8只),吗啡组(8只)和纳洛酮组(8只),15只不符合要求已剔除.运用脑立体定位、核团插管、药物微量注射和多导睡眠描记技术,观察海马CA1区注射药物后大鼠睡眠-觉醒指标变化情况.结果 与对照组比较,吗啡组大鼠海马CA1区双侧微量注射吗啡后觉醒时间增加32.0%(P<0.05),总睡眠时间减少23.7%(P<0.05),其中深慢波睡眠减少76.1%(P<0.05).纳洛酮组大鼠海马CA1区双侧微量注射纳洛酮后觉醒时间减少34.1%(P<0.01),总睡眠时间增加25.3%(P<0.01),其中深慢波睡眠增加247.8%(P<0.01).结论 吗啡在海马参与对睡眠-觉醒周期的调节,且吗啡对睡眠的影响主要是通过改变深慢波睡眠成分实现的.

  6. Model-Based Assessment of an In-Vivo Predictive Relationship from CA1 to CA3 in the Rodent Hippocampus

    OpenAIRE

    Sandler, Roman A.; Song, Dong; Hampson, Robert E.; Deadwyler, Sam A.; Berger, Theodore W; Marmarelis, Vasilis Z.

    2014-01-01

    Although an anatomical connection from CA1 to CA3 via the Entorhinal Cortex (EC) and through backprojecting interneurons has long been known it exist, it has never been examined quantitatively on the single neuron level, in the in-vivo nonpatholgical, nonperturbed brain. Here, single spike activity was recorded using a multi-electrode array from the CA3 and CA1 areas of the rodent hippocampus (N=7) during a behavioral task. The predictive power from CA3→CA1 and CA1→CA3 was examined by constru...

  7. Model-based asessment of an in-vivo predictive relationship from CA1 to CA3 in the rodent hippocampus.

    Science.gov (United States)

    Sandler, Roman A; Song, Dong; Hampson, Robert E; Deadwyler, Sam A; Berger, Theodore W; Marmarelis, Vasilis Z

    2015-02-01

    Although an anatomical connection from CA1 to CA3 via the Entorhinal Cortex (EC) and through backprojecting interneurons has long been known it exist, it has never been examined quantitatively on the single neuron level, in the in-vivo nonpatholgical, nonperturbed brain. Here, single spike activity was recorded using a multi-electrode array from the CA3 and CA1 areas of the rodent hippocampus (N = 7) during a behavioral task. The predictive power from CA3→CA1 and CA1→CA3 was examined by constructing Multivariate Autoregressive (MVAR) models from recorded neurons in both directions. All nonsignificant inputs and models were identified and removed by means of Monte Carlo simulation methods. It was found that 121/166 (73 %) CA3→CA1 models and 96/145 (66 %) CA1→CA3 models had significant predictive power, thus confirming a predictive 'Granger' causal relationship from CA1 to CA3. This relationship is thought to be caused by a combination of truly causal connections such as the CA1→EC→CA3 pathway and common inputs such as those from the Septum. All MVAR models were then examined in the frequency domain and it was found that CA3 kernels had significantly more power in the theta and beta range than those of CA1, confirming CA3's role as an endogenous hippocampal pacemaker.

  8. Path Creation, Path Dependence and Breaking Away from the Path

    DEFF Research Database (Denmark)

    Wang, Jens Erik; Hedman, Jonas; Tuunainen, Virpi Kristiina

    2016-01-01

    The explanation of how and why firms succeed or fail is a recurrent research challenge. This is particularly important in the context of technological innovations. We focus on the role of historical events and decisions in explaining such success and failure. Using a case study of Nokia, we develop...... the importance of intermediate outcomes, which in the case of Nokia was the importance of software ecosystems and adaptable mobile devices. Furthermore, we show how the layers of path dependence mutually reinforce each other and become stronger....

  9. INCIDENCE, RISK FACTORS AND COMPLICATIONS OF ACUTE PERFORATED AND NON - PERFORATED APPENDICITIS IN A RURAL SETUP OF ANDHRA PRADESH

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2015-05-01

    Full Text Available Appendicitis is one of the most common surgical emergencies. The incidence of appendicitis and chances of complication in the form of perforation are dependent on both the patients and non - patient factors . There are various studies conducted to address this problem, but there are no studies conducted to look in to the incidence of appendicitis in east Godavari district of Andhra Pradesh. Our study was aimed to bridge thi s gap. METHOD S AND MATERIALS: this was a retrospective study, patient data from 2009 - 2014 was analyzed and the age, distance from hospital, educational and socioeconomic background of the patients was collected. The duration between first appearance of sy mptoms and hospitalization was recorded. The incidence of post - op complication was also recorded. RESULTS: T he incidence of perforation was 15% in our study population, most of the patients were from low socioeconomic group and having income less than 5000 /month. The middle age group between 30 - 40 years was commonly affected by the appendicitis. The time laps between appearance of symptoms and hospitalization was found to be a predominant factor in the perforation. Surgical site infection was most common co mplication in the patients treated. CONCLUSION: T he incidence of perforation is still high and the time laps between first appearance of symptoms and hospitalization is a major determinant of perforation or complication in the appendicitis.

  10. Acoustic Liner Drag: Measurements on Novel Facesheet Perforate Geometries

    Science.gov (United States)

    Howerton, Brian M.; Jones, Michael G.

    2016-01-01

    Interest in characterization of the aerodynamic drag of acoustic liners has increased in the past several years. This paper details experiments in the NASA Langley Grazing Flow Impedance Tube to quantify the relative drag of several perforate-over-honeycomb liner configurations at flow speeds of centerline flow Mach number equals 0.3 and 0.5. Various perforate geometries and orientations are investigated to determine their resistance factors using a static pressure drop approach. Comparison of these resistance factors gives a relative measurement of liner drag. For these same flow conditions, acoustic measurements are performed with tonal excitation from 400 to 3000 hertz at source sound pressure levels of 140 and 150 decibels. Educed impedance and attenuation spectra are used to determine the impact of variations in perforate geometry on acoustic performance.

  11. Perforation of the sinus membrane during sinus floor elevation

    DEFF Research Database (Denmark)

    von Arx, Thomas; Fodich, Ivo; Bornstein, Michael M;

    2014-01-01

    PURPOSE: To analyze the frequency of perforation of the sinus membrane during maxillary sinus floor elevation (SFE) and to assess possible risk factors. MATERIALS AND METHODS: Seventy-seven cases of SFE performed with a lateral window approach were evaluated retrospectively. Clinical and radiogra......PURPOSE: To analyze the frequency of perforation of the sinus membrane during maxillary sinus floor elevation (SFE) and to assess possible risk factors. MATERIALS AND METHODS: Seventy-seven cases of SFE performed with a lateral window approach were evaluated retrospectively. Clinical...... (presence and height of septum, height of residual ridge, thickness of lateral sinus wall, width of antrum, and thickness and status of sinus membrane). RESULTS: The following factors presented with at least a 10% difference in rates of perforations: smokers (46.2%) versus nonsmokers (23.4%), simultaneous...... the lateral window approach....

  12. [A case of perforated xanthogranulomatous cholecystitis presenting as biloma].

    Science.gov (United States)

    Ahn, Yeon Jeong; Kim, Tae Hyo; Moon, Sung Won; Choi, Su Nyoung; Kim, Hyun Jin; Jung, Woon Tae; Lee, Ok Jae; Ko, Gyung Hyuck

    2011-09-25

    Xanthogranulomatous cholecystitis is an unusual inflammatory disease of the gallbladder characterized by severe proliferative fibrosis and the accumulation of lipid-laden macrophages in areas of destructive inflammation. Its macroscopic appearance may occasionally be confused with gallbladder carcinoma. We present a case of perforated xanthogranulomatous cholecystitis presenting as biloma. An 80-year-old woman was referred to our hospital with a 1-week history of abdominal pain and febrile sensation. Abdominal CT showed a biloma in the subhepatic area. The follow-up CT showed that the biloma increased in size. Therefore, ultrasonography-guided aspiration was performed. The aspirated fluid/serum bilirubin ratio was greater than 5, which was strongly suggestive of bile leakage complicated by perforated cholecystitis. She underwent a laparoscopic cholecystectomy with cyst aspiration and adhesiolysis. A histological diagnosis of perforated xanthogranulomatous cholecystitis was made.

  13. Primary tubercular caecal perforation: a rare clinical entity

    Directory of Open Access Journals (Sweden)

    Moses Sonia

    2010-03-01

    Full Text Available Abstract Background Intestinal tuberculosis is a common problem in endemic areas, causing considerable morbidity and mortality. An isolated primary caecal perforation of tubercular origin is exceptionally uncommon. Case presentation We report the case of a 39 year old male who presented with features of perforation peritonitis, which on laparotomy revealed a caecal perforation with a dusky appendix. A standard right hemicolectomy with ileostomy and peritoneal toileting was done. Histopathology revealed multiple transmural caseating granulomas with Langerhans-type giant cells and acid-fast bacilli, consistent with tuberculosis, present only in the caecum. Conclusions We report this extremely rare presentation of primary caecal tuberculosis to sensitize the medical fraternity to its rare occurrence, which will be of paramount importance owing to the increasing incidence of tuberculosis all over the world, especially among the developing countries.

  14. [A case of jejunal perforation in gallstone ileus].

    Science.gov (United States)

    Taira, Akiko; Yamada, Masami; Takehira, Yasunori; Kageyama, Fujito; Yoshii, Shigeto; Murohisa, Gou; Yoshida, Kenichi; Iwaoka, Yasushi; Terai, Tomohiro; Uotani, Takahiro; Watanabe, Shinya; Noritake, Hidenao; Ikematu, Yoshito; Kanai, Toshikazu

    2008-04-01

    Gallstone ileus is a rare but important cause of small bowel obstruction in the geriatric population. A 65-year-old man with a twenty year history of cholecystolithiasis was admitted to our hospital with abdominal pain and vomiting. Physical exams showed abdominal defence and rebound tenderness. A plain abdominal X-ray suggested a small bowel obstruction and pneumobilia. CT scan revealed a 2.5-cm gallstone at the jejunum and air in the biliary tree. The patient underwent a emergency laparotomy based on a diagnosis of panperitonitis with a perforation associated with gallstone ileus. Operative findings revealed a jejunal perforation and a impacted stone on the anal side of perforation. Enterolithotomy and jejunal resection were performed with cholecystectomy and repairment of the cholecystoduodenal fistula.

  15. Distal thoracic oesophageal perforation secondary to blunt trauma: Case report

    Directory of Open Access Journals (Sweden)

    Tandon Ruchi

    2007-03-01

    Full Text Available Abstract Background Traumatic perforation of the distal oesophagus due to blunt trauma is a very rare condition and is still associated with a significant morbidity and mortality. This is further exacerbated by delayed diagnosis and management as symptoms and signs are often masked by or ascribed to more common blunt thoracic injuries. Case report We present a case of a distal oesophageal perforation, secondary to a fall from a third storey window, which was masked by concomitant thoracic injuries and missed on both computed tomography imaging and laparotomy. The delay in his diagnosis significantly worsened the patient's recovery by allowing the development of an overwhelming chest sepsis that contributed to his death. Conclusion Early identification of an intrathoracic oesophageal perforation requires deliberate consideration and is essential to ensure a favorable outcome. Treatment should be individualised taking into account the nature of the oesophageal defect, time elapsed from injury and the patient's general condition.

  16. Pedicled perforator flaps in the head and neck.

    Science.gov (United States)

    Hofer, Stefan O P; Mureau, Marc A M

    2010-10-01

    Perforator flaps, since their first description in 1989, have in many ways revolutionized reconstructive surgery. Whereas little more than a decade ago many surgeons were still hesitant to fully trust perforator flaps to be a reliable option, nowadays these flaps are often first choice. Investigators have to remain critical, however, of their advances and realize that not every reconstruction will require or benefit from a perforator flap, as previously well-established, nonperforator flaps still have their indication and can give excellent results. The most important skill in reconstructive surgery of the head and neck is not cutting the flap but assessing the defect, planning the reconstruction, and choosing wisely from the ever-increasing options available.

  17. Risk factors in patients surgically treated for peptic ulcer perforation

    DEFF Research Database (Denmark)

    Møller, Morten Hylander; Shah, Kamran; Bendix, Jørgen;

    2009-01-01

    OBJECTIVE: The overall mortality for patients undergoing surgery for perforated peptic ulcer has increased despite improvements in perioperative monitoring and treatment. The objective of this study was to identify and describe perioperative risk factors in order to identify ways of optimizing...... the treatment and to improve the outcome of patients with perforated peptic ulcer. MATERIAL AND METHODS: Three hundred and ninety-eight patients undergoing emergency surgery in four university hospitals in Denmark were included in the study. Information regarding the pre-, intra- and postoperative phases were...... insufficiency upon admission and insufficient postoperative nutrition have been added to the list of independent risk factors for death within 30 days of surgery in patients with peptic ulcer perforation. Finding that shock upon admission, reduced albumin blood levels upon admission, renal insufficiency upon...

  18. Microsporidium infection and perforation peritonitis: A rare association

    Directory of Open Access Journals (Sweden)

    Nadeem Tanveer

    2015-01-01

    Full Text Available Enteric protozoan infections are a well-documented cause of diarrhea in immunocompromised patients. Special stains on stool specimens are routinely performed in such patients to diagnose these protozoa namely cryptosporidium, microsporidium, and isospora. Duodenal and jejunal biopsies can also be performed to obtain a tissue diagnosis. We report a case of microsporidium enteritis diagnosed on histopathological examination of small bowel resection specimen in a case of perforation peritonitis. The patient was a known HIV-positive on antiretroviral treatment for 2 years and on antitubercular treatment for 3 months. This case report highlights the importance of carefully screening the resection specimens for protozoal infections in immunocompromised individuals. The association of perforation peritonitis and microsporidium is rare. Hence, the possibility that untreated microsporidium infection can lead to perforation cannot be ruled out.

  19. Computational analysis of acoustic transmission through periodically perforated interfaces

    Directory of Open Access Journals (Sweden)

    Rohan E.

    2009-06-01

    Full Text Available The objective of the paper is to demonstrate the homogenization approach applied to modelling the acoustic transmission on perforated interfaces embedded in the acoustic fluid. We assume a layer, with periodically perforated obstacles, separating two half-spaces filled with the fluid. The homogenization method provides limit transmission conditions which can be prescribed at the homogenized surface representing the "limit" interface. The conditions describe relationship between jump of the acoustic pressures and the transversal acoustic velocity, on introducing the "in-layer pressure" which describes wave propagation in the tangent directions with respect to the interface.This approach may serve as a relevant tool for optimal design of devices aimed at attenuation of the acoustic waves, such as the engine exhaust mufflers or other structures fitted with sieves and grillages. We present numerical examples of wave propagation in a muffler-like structure illustrating viability of the approach when complex 3D geometries of the interface perforation are considered.

  20. Presynaptic ultrastructural plasticity along CA3→CA1 axons during long-term potentiation in mature hippocampus.

    Science.gov (United States)

    Bourne, Jennifer N; Chirillo, Michael A; Harris, Kristen M

    2013-12-01

    In area CA1 of the mature hippocampus, synaptogenesis occurs within 30 minutes after the induction of long-term potentiation (LTP); however, by 2 hours many small dendritic spines are lost, and those remaining have larger synapses. Little is known, however, about associated changes in presynaptic vesicles and axonal boutons. Axons in CA1 stratum radiatum were evaluated with 3D reconstructions from serial section electron microscopy at 30 minutes and 2 hours after induction of LTP by theta-burst stimulation (TBS). The frequency of axonal boutons with a single postsynaptic partner was decreased by 33% at 2 hours, corresponding perfectly to the 33% loss specifically of small dendritic spines (head diameters complement postsynaptic ultrastructural plasticity during LTP.

  1. Responses of CA1 pyramidal neurons in rat hippocampus to transient forebrain ischemia: an in vivo intracellular recording study.

    Science.gov (United States)

    Xu, Z C; Pulsinelli, W A

    1994-04-25

    The electrophysiological responses of CA1 pyramidal neurons to 5 min forebrain ischemia were studied with intracellular recording and staining techniques in vivo. The baseline membrane potential rapidly depolarized to approximately -20 mV about 3 min after the onset of ischemia and began to repolarize 1-3 min after recirculation. The amplitude of this ischemic depolarization (ID) was related directly to the severity of ischemia and its latency of onset was inversely related to brain temperature. Spontaneous synaptic activity ceased shortly after ischemia onset while the evoke synaptic potentials lasted until shortly before the onset of ID. Inhibitory postsynaptic potentials (IPSPs) disappeared earlier than excitatory postsynaptic potentials (EPSPs) and the membrane input resistance of CA1 neurons increased after the onset of ischemia.

  2. Atorvastatin increases dynamin 1 expression in hippocampal CA1 region in a rat model of vascular dementia

    Institute of Scientific and Technical Information of China (English)

    Qinghua Li; Wensheng Zhou

    2011-01-01

    The current study examined a rat model of vascular dementia. The model rats exhibited obvious morphological and ultrastructural changes in neurons in the brain, and significantly reduced dynamin 1 expression in hippocampal CA1 region along with decreased learning and memory performance. Following atorvastatin treatment, the morphology and ultrastructure of cells in the model rat brain were significantly improved, dynamin 1 expression in hippocampal CA1 region was significantly enhanced, and learning and memory ability was significantly improved. The results demonstrated that impaired learning and memory abilities in vascular dementia model rats were closely correlated with decreased dynamin 1 expression. These findings indicate that atorvastatin can protect model rats against cognitive impairment by increasing dynamin 1 expression.

  3. Electron-correlation-induced band renormalization and Mott transition in Ca1-xSrxVO3

    Institute of Scientific and Technical Information of China (English)

    Wang Guang-Tao; Zhang Min-Ping; Zheng Li-Hua

    2011-01-01

    We present the local density approximate+Gutzwiller results for the electronic structure of Ca1-xSryVO3. The substitution of Sr 2+ by Ca2+ reduces the bandwidth,as the V-O-V bond angle decreases from 180°for SrVO3 to about 160°for CaVO3. However,we find that the bandwidth decrease induced by the V-O-V bond angle decrease is smaller as compared to that induced by electron correlation. In correlated electron systems,such as Ca1-xSr. V03,the correlation effect of 3d electrons plays a leading role in determining the bandwidth. The electron correlation effect and crystal field splitting collaboratively determine whether the compounds will be in a metal state or in a Mottinsulator phase.

  4. Low doses of alcohol potentiate GABA sub B inhibition of spontaneous activity of hippocampal CA1 neurons in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Criado, J.R.; Thies, R. (Univ. of Oklahoma, Oklahoma City (United States))

    1991-03-11

    Low doses of alcohol facilitate firing of hippocampal neurons. Such doses also enhance the inhibitory actions of GABA. Alcohol is known to potentiate inhibition via GABA{sub A} receptors. However, the effects of alcohol on GABA{sub B} receptor function are not understood. Spontaneous activity of single units was recorded from CA1 neurons of male rats anesthetized with 1.0% halothane. Electrical recordings and local application of drugs were done with multi-barrel pipettes. CA1 pyramidal neurons fired spontaneous bursts of action potentials. Acute alcohol decreased the interval between bursts, a mild excitatory action. Alcohol also more than doubled the period of complete inhibition produced by local application of both GABA and baclofen. These data suggest that GABA{sub B}-mediated inhibition is also potentiated by low doses of alcohol.

  5. High-energy gas fracturing in cased and perforated wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Cuderman, J.F.

    1986-06-01

    A propellant-based technology, High-Energy Gas Fracturing (HEGF), has been applied to fracturing through perforations in cased boreholes. HEGF is a tailored-pulse fracturing technique originally developed by Sandia National Laboratories for application in uncased, liquid-free gas wells in Appalachian Devonian shales. Because most oil and gas wells are liquid filled as well as cased and perforated, the potential impact of present research is significantly broader. A number of commercial tailored-pulse fracturing services, using a variety of explosives or propellants, are currently available. Present research provides valuable insight into phenomena that occur in those stimulations. The use of propellants that deflagrate or burn rather than detonate, as do high-order explosives, permits controlled buildup of pressure in the wellbore. The key to successful stimulation in cased and perforated wellbores is to control the pressure buildup of the combustion gases to maximize fracturing without destroying the casing. Eight experiments using cased and perforated wellbore were conducted in a tunnel complex at the Department of Energy's Nevada Test Site, which provides a realistic in situ stress environment (4 to 10 MPa (600 to 1500 psi)) and provides access for mineback to directly observe fracturing obtained. Primary variables in the experiments include propellant burn rate and amount of propellant used, presence or absence of liquid in the wellbore, in situ stress orientation, and perforation diameter, density, and phasing. In general, the presence of liquid in the borehole results in a much faster pressure risetime and a lower peak pressure for the same propellant charge. Fracture surfaces proceed outward along lines of perforations as determined by phasing, then gradually turn toward the hydraulic fracture direction. 8 refs., 23 figs., 3 tabs.

  6. 小鼠海马CA1区锥体神经元树突棘的发育%Dendritic spine development of mouse hippocampal CA1 pyramidal neurons

    Institute of Scientific and Technical Information of China (English)

    刘畅; 范文娟; 程维杰; 左曙光; 邓锦波

    2012-01-01

    Objective To investigate the developmental characteristics of dendritic spines in mouse hippocampal CA1 pyramidal neurons by analysing the spine density and morphological changes. Methods Fifty mice were collected at postnatal days ( P ) 0, 5, 10, 20 and 30, 10 mice for each age. Dil diolistic labeling with gene gun was performed to observe dendritic spines development in mouse hippocampal CA1 pyramidal neurons. High quality labeled neurons were examined and photographed under a confocal microscope, whereas the ultrastructure of spines was observed under a transmission electron microscope. Results Dendritic spines changed their morphology and density with mouse development in response to neuronal activity. The smooth endoplasmic reticulum and spine apparatus in dendritic spines of hippocampal CA1 were observed with electron microscopy analysis, which might be involved in the regulation of plasticity at individual synapses. Conclusion The development of dendritic spines may be closely related to synaptogenesis and the formation of synaptic plasticity.%目的 对小鼠海马CA1区锥体神经元正常发育中树突棘密度及各种形态变化进行分析测定,为深入研究突触发生及突触可塑性提供直接的形态学依据.方法 分别取出生后0、5、10、20及30d 5个年龄段的C57BL/6小鼠各10只,采用基因枪对小鼠海马CA1区锥体神经元树突棘进行亲脂性荧光染料DiI标记,通过激光共焦显微镜对其进行观察分析;同时利用透射电镜技术对树突棘的超微结构进行分析.结果 树突棘的形态、大小及其密度随小鼠发育而变化,成熟树突棘内部存在滑面内质网与棘器,可能参与了突触后膜结合蛋白及其转运体的合成.结论 树突棘的发育过程与突触连接的形成以及突触可塑性密切相关.

  7. An unusual case of duodenal perforation caused by a blister pack: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Si-Yuan Yao

    2015-01-01

    Conclusion: Unnoticed ingestion of blister packs can cause duodenal perforation. Although prompt management is necessary, duodenal perforation, especially in the third portion, may be potentially fatal.

  8. Laparoscopic Lavage Is Feasible and Safe for the Treatment of Perforated Diverticulitis With Purulent Peritonitis

    DEFF Research Database (Denmark)

    Angenete, Eva; Thornell, Anders; Burcharth, Jakob

    2016-01-01

    OBJECTIVE: To evaluate short-term outcomes of a new treatment for perforated diverticulitis with purulent peritonitis in a randomized controlled trial. BACKGROUND: Perforated diverticulitis with purulent peritonitis (Hinchey III) has traditionally been treated with surgery including colon resection...

  9. Spontaneous perforation of the rectosigmoid colon: a report of 2 cases

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Spontaneous perforation of rectosigmoid colon is rare but usually results in severe peritonitis, with very high mortality. Two cases of spontaneous rectosigmoid perforations are reported here along with a brief literatures review.

  10. Optogenetic identification of an intrinsic cholinergically driven inhibitory oscillator sensitive to cannabinoids and opioids in hippocampal CA1.

    Science.gov (United States)

    Nagode, Daniel A; Tang, Ai-Hui; Yang, Kun; Alger, Bradley E

    2014-01-01

    Neuronal electrical oscillations in the theta (4-14 Hz) and gamma (30-80 Hz) ranges are necessary for the performance of certain animal behaviours and cognitive processes. Perisomatic GABAergic inhibition is prominently involved in cortical oscillations driven by ACh release from septal cholinergic afferents. In neocortex and hippocampal CA3 regions, parvalbumin (PV)-expressing basket cells, activated by ACh and glutamatergic agonists, largely mediate oscillations. However, in CA1 hippocampus in vitro, cholinergic agonists or the optogenetic release of endogenous ACh from septal afferents induces rhythmic, theta-frequency inhibitory postsynaptic currents (IPSCs) in pyramidal cells, even with glutamatergic transmission blocked. The IPSCs are regulated by exogenous and endogenous cannabinoids, suggesting that they arise from type 1 cannabinoid receptor-expressing (CB1R+) interneurons - mainly cholecystokinin (CCK)-expressing cells. Nevertheless, an occult contribution of PV-expressing interneurons to these rhythms remained conceivable. Here, we directly test this hypothesis by selectively silencing CA1 PV-expressing cells optogenetically with halorhodopsin or archaerhodopsin. However, this had no effect on theta-frequency IPSC rhythms induced by carbachol (CCh). In contrast, the silencing of glutamic acid decarboxylase 2-positive interneurons, which include the CCK-expressing basket cells, strongly suppressed inhibitory oscillations; PV-expressing interneurons appear to play no role. The low-frequency IPSC oscillations induced by CCh or optogenetically stimulated ACh release were also inhibited by a μ-opioid receptor (MOR) agonist, which was unexpected because MORs in CA1 are not usually associated with CCK-expressing cells. Our results reveal novel properties of an inhibitory oscillator circuit within CA1 that is activated by muscarinic agonists. The oscillations could contribute to behaviourally relevant, atropine-sensitive, theta rhythms and link cannabinoid and

  11. Hippocampal Deletion of BDNF Gene Attenuates Gamma Oscillations in Area CA1 by Up-Regulating 5-HT3 Receptor

    OpenAIRE

    Ying Huang; Alexei Morozov

    2011-01-01

    BACKGROUND: Pyramidal neurons in the hippocampal area CA3 express high levels of BDNF, but how this BDNF contributes to oscillatory properties of hippocampus is unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we examined carbachol-induced gamma oscillations in hippocampal slices lacking BDNF gene in the area CA3. The power of oscillations was reduced in the hippocampal area CA1, which coincided with increases in the expression and activity of 5-HT3 receptor. Pharmacological block of this recept...

  12. Large Magnetic Entropy Effect in La2/3Ca1/3MnO3

    Institute of Scientific and Technical Information of China (English)

    彭振生

    2004-01-01

    The magnetocaloric effect in the colossal magnetoresistance material La2/3Ca1/3MnO3 was studied.From the measurements of temperature dependence of magnetization in various magnetic fields,the large magnetic entropy change associated with the ferromagnetic-paramagnetic transition was discovered.This result suggests that perovskite manganites are suitable candidates as working substance in magnetic refrigeration technology.

  13. Study of gel grown mixed crystals of BaCa(1–)(IO3)4

    Indian Academy of Sciences (India)

    S L Garud; N K Mahajan; K B Saraf

    2009-04-01

    The growth of mixed crystals of BaCa1–(IO3)4 were carried out with simple gel method. The effect of various parameters such as pH of gel solution, gel concentration, gel setting time, concentration of reactants on the growth was studied. Crystals having different morphologies and habits were obtained. The grown crystals were characterized by XRD, FT–IR, EDAX, TGA, DTA and DSC.

  14. Specificity and actions of an arylaspartate inhibitor of glutamate transport at the Schaffer collateral-CA1 pyramidal cell synapse.

    Directory of Open Access Journals (Sweden)

    Weinan Sun

    Full Text Available In this study we characterized the pharmacological selectivity and physiological actions of a new arylaspartate glutamate transporter blocker, L-threo-ß-benzylaspartate (L-TBA. At concentrations up to 100 µM, L-TBA did not act as an AMPA receptor (AMPAR or NMDA receptor (NMDAR agonist or antagonist when applied to outside-out patches from mouse hippocampal CA1 pyramidal neurons. L-TBA had no effect on the amplitude of field excitatory postsynaptic potentials (fEPSPs recorded at the Schaffer collateral-CA1 pyramidal cell synapse. Excitatory postsynaptic currents (EPSCs in CA1 pyramidal neurons were unaffected by L-TBA in the presence of physiological extracellular Mg(2+ concentrations, but in Mg(2+-free solution, EPSCs were significantly prolonged as a consequence of increased NMDAR activity. Although L-TBA exhibited approximately four-fold selectivity for neuronal EAAT3 over glial EAAT1/EAAT2 transporter subtypes expressed in Xenopus oocytes, the L-TBA concentration-dependence of the EPSC charge transfer increase in the absence of Mg(2+ was the same in hippocampal slices from EAAT3 +/+ and EAAT3 -/- mice, suggesting that TBA effects were primarily due to block of glial transporters. Consistent with this, L-TBA blocked synaptically evoked transporter currents in CA1 astrocytes with a potency in accord with its block of heterologously expressed glial transporters. Extracellular recording in the presence of physiological Mg(2+ revealed that L-TBA prolonged fEPSPs in a frequency-dependent manner by selectively increasing the NMDAR-mediated component of the fEPSP during short bursts of activity. The data indicate that glial glutamate transporters play a dominant role in limiting extrasynaptic transmitter diffusion and binding to NMDARs. Furthermore, NMDAR signaling is primarily limited by voltage-dependent Mg(2+ block during low-frequency activity, while the relative contribution of transport increases during short bursts of higher frequency

  15. Melamine Alters Glutamatergic Synaptic Transmission of CA3-CA1 Synapses Presynaptically Through Autophagy Activation in the Rat Hippocampus.

    Science.gov (United States)

    Zhang, Hui; Wang, Hui; Xiao, Xi; Zhang, Tao

    2016-01-01

    Melamine is an industrial chemical that can cause central nervous system disorders including excitotoxicity and cognitive impairment. Its illegal use in powdered baby formula was the focus of a milk scandal in China in 2008. One of our previous studies showed that melamine impaired glutamatergic transmission in rat hippocampal CA1 pyramidal cells. However, the underlying mechanism of action of melamine is unclear, and it is unknown if the CA3-CA1 pathway is directly involved. In the present study, a whole-cell patch-clamp technique was employed to investigate the effect of melamine on the hippocampal CA3-CA1 pathway in vitro. Both the evoked excitatory postsynaptic current (eEPSC) and the paired-pulse ratio (PPR) were recorded. Furthermore, we examined whether autophagy was involved in glutamatergic transmission alterations induced by melamine. Our data showed that melamine significantly increased the amplitude of eEPSCs in a dose-dependent manner. Inhibition of the N-methyl-D-aspartic acid receptor did not prevent the increase in eEPSC amplitude. In addition, the PPR was remarkably decreased by a melamine concentration of 5 × 10(-5) g/mL. It was found that autophagy could be activated by melamine and an autophagy inhibitor, 3-MA, prevented the melamine-induced increase in eEPSC amplitude. Overall, our results show that melamine presynaptically alters glutamatergic synaptic transmission of hippocampal CA3-CA1 synapses in vitro and this is likely associated with autophagy alteration.

  16. Spatiotemporal Progression of Microcalcification in the Hippocampal CA1 Region following Transient Forebrain Ischemia in Rats: An Ultrastructural Study.

    Directory of Open Access Journals (Sweden)

    Tae-Ryong Riew

    Full Text Available Calcification in areas of neuronal degeneration is a common finding in several neuropathological disorders including ischemic insults. Here, we performed a detailed examination of the onset and spatiotemporal profile of calcification in the CA1 region of the hippocampus, where neuronal death has been observed after transient forebrain ischemia. Histopathological examinations showed very little alizarin red staining in the CA1 pyramidal cell layer until day 28 after reperfusion, while prominent alizarin red staining was detected in CA1 dendritic subfields, particularly in the stratum radiatum, by 14 days after reperfusion. Electron microscopy using the osmium/potassium dichromate method and electron probe microanalysis revealed selective calcium deposits within the mitochondria of degenerating dendrites at as early as 7 days after reperfusion, with subsequent complete mineralization occurring throughout the dendrites, which then coalesced to form larger mineral conglomerates with the adjacent calcifying neurites by 14 days after reperfusion. Large calcifying deposits were frequently observed at 28 days after reperfusion, when they were closely associated with or completely engulfed by astrocytes. In contrast, no prominent calcification was observed in the somata of CA1 pyramidal neurons showing the characteristic features of necrotic cell death after ischemia, although what appeared to be calcified mitochondria were noted in some degenerated neurons that became dark and condensed. Thus, our data indicate that intrahippocampal calcification after ischemic insults initially occurs within the mitochondria of degenerating dendrites, which leads to the extensive calcification that is associated with ischemic injuries. These findings suggest that in degenerating neurons, the calcified mitochondria in the dendrites, rather than in the somata, may serve as the nidus for further calcium precipitation in the ischemic hippocampus.

  17. Pharyngeal perforation after blunt cervical trauma in child.

    Science.gov (United States)

    Svetlikova, Mariana; Starek, Ivo; Spenerova, Michaela; Potesil, Jan; Sulla, Igor; Hucko, Csaba; Mihal, Vladimir; Balik, Vladimir

    2014-01-01

    Pharyngeal perforation caused by non-penetrating cervical trauma is an extremely rare clinical entity both in adults and children. Data concerning management of this type of injury are quite rare in surgical and even scarcer in pediatric literature. Since delay in treatment may be associated with life-threatening complications, prompt diagnosis coupled with appropriate therapy is essential for achieving favorable clinical outcome. To the best of authors' knowledge, the present study illustrates for the first time the experience with successful treatment of pharyngeal perforation caused by a blunt cervical trauma in a child.

  18. Outcome of surgical treatment of intestinal perforation in typhoid fever

    Institute of Scientific and Technical Information of China (English)

    Aziz; Sümer; zgür; Kemik; Ahmet; Cumhur; Dülger; Aydemir; Olmez; Ismail; Hasirci; Erol; Kisli; Vedat; Bayrak; Gulay; Bulut; etin; Kotan

    2010-01-01

    AIM:To represent our clinical experience in the treatment of intestinal perforation arising from typhoid fever.METHODS:The records of 22 surgically-treated patients with typhoid intestinal perforation were evaluated retrospectively.RESULTS:There were 18 males and 4 females,mean age 37 years(range,8-64 years).Presenting symptoms were fever,abdominal pain,diarrhea or constipation.Sixteen cases were subjected to segmental resection and end-to-end anastomosis,while 3 cases received 2-layered primary repair foll...

  19. Appendicular involvement in perforated sigmoid disease: US and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Ripolles, T.; Concepcion, L.; Martinez-Perez, M.J.; Morote, V. [Dept. of Radiology, Dr. Peset Hospital, Valencia (Spain)

    1999-05-01

    We describe four patients in whom ultrasound (US) and/or computed tomography (CT) demonstrated a thickened appendix, secondarily enlarged due to perforated sigmoid diverticulitis (n = 2) or carcinoma (n = 2). The underlying pathology was correctly recognized in all cases. Secondary thickening of the appendix due to perforated sigmoid disease provides a potential pitfall mainly on US and may lead to an incorrect diagnosis and thus to unnecessary surgery or a wrong surgical intervention. Although US alone is enough to diagnose periappendicitis and sigmoid disease, combined use of US and CT may improve assessment of its origin and extension. (orig.) With 4 figs., 19 refs.

  20. Gastric Perforation and Phlegmon Formation by Foreign Body Ingestion

    Directory of Open Access Journals (Sweden)

    Albert Alejandro Avila Alvarez

    2014-08-01

    Full Text Available This is a case report of foreign body ingestion in a suicide attempt resulting in gastric perforation and phlegmon formation during a subsequent 6 month period that eventually required surgical intervention. The patient had a prolonged course because she did not report a history of foreign body ingestion and the initial evaluating physicians had no suspicion about possible foreign body ingestion and may have missed important findings on physical examination. Gastric perforation by a foreign object  may have a slow course rather than presenting acute abdomen. The realization of a proper physical examination in the emergency department is key to an accurate diagnosis.

  1. To drain or not to drain in perforated peptic ulcer

    Directory of Open Access Journals (Sweden)

    Zafer Kilbas

    2012-02-01

    Full Text Available In their study, published in the current issue of the Journal of Experimental and Integrative Medicine, Ansari et al investigated the role of prophylactic abdominal drain usage in perforated peptic ulcer (PPU, a frequently performed surgical procedure in the emergency departments. Surgical treatment of PPU has not changed much, i.e. primary closure of the perforation and careful cleansing of the abdominal cavity, since it was described by Johann von Mikulicz-Radecki (1850-1905. There have been different applications related to drain usage and drain numbers in different centers. While a single drain... [J Exp Integr Med 2012; 2(1.000: 45-46

  2. Isolated perforation of a duodenal diverticulum following blunt abdominal trauma

    Directory of Open Access Journals (Sweden)

    Metcalfe Matthew

    2010-01-01

    Full Text Available Only 10% of duodenal diverticula are symptomatic. We present the case of a man who fell from a height of 6 ft, landing on his abdomen and presenting 4 h later with severe back pain and a rigid abdomen. At laparotomy, a perforated retroperitoneal duodenal diverticulum was found and repaired with an omental patch. No other injury was noted. Not only is this perforation unusual, but the absence of other injuries sustained during this minor blunt trauma makes this case unique. This case highlights the need for a high index of suspicion when managing patients with back or abdominal pain following minor trauma.

  3. Unusual scintigraphic appearance of perforation of the common bile duct

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, M.O.; Tauxe, W.N.; Scott, J.W.; Aldrete, J.S.

    1983-12-01

    This report deals with the diagnosis of perforation of the common bile duct into the lesser sac by HIDA cholescintigraphy. The first hour images after injection were suggestive of biliary obstruction. Subsequent images demonstrated unusual accumulations of the activity into the lesser sac and retroperitoneal potential spaces. Careful correlation between scintigraphic and surgical findings were undertaken. The case is reported to demonstrate the scintigraphic findings in choledochal perforation and to stress the importance of carrying out late images when the initial ones are abnormal.

  4. Perforated ileal duplication cyst with haemorrhagic pseudocyst formation

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Im Kyung; Kim, Bong Soo; Kim, Heung Chul; Lee, In Sun; Hwang, Woo Chul [Department of Radiology, College of Medicine, Hallym University (Korea); Namkung, Sook [Department of Radiology, College of Medicine, Hallym University (Korea); Department of Radiology, Chuncheon Sacred Heart Hospital, 153 Kyo-dong, Chuncheon, Kangwon-do, 200-704 (Korea)

    2003-07-01

    Duplication cysts of the gastrointestinal tract are rare congenital abnormalities. Ectopic gastric mucosa, which can be found in duplications, may cause peptic ulceration, gastrointestinal bleeding or perforation. We report a 1-year-old boy with a perforated ileal duplication cyst with haemorrhagic pseudocyst formation caused by peptic ulceration of the duplication cyst. It presented a snowman-like appearance consisting of a small, thick-walled, true enteric cyst and a large, thin-walled haemorrhagic pseudocyst on US and CT. It is an unusual manifestation of a duplication cyst, which has not been reported in the English language literature. (orig.)

  5. Changes in ensemble activity of hippocampus CA1 neurons induced by chronic morphine administration in freely behaving mice.

    Science.gov (United States)

    Liu, F; Jiang, H; Zhong, W; Wu, X; Luo, J

    2010-12-15

    The hippocampus plays an important role in the formation of new memories and spatial navigation. Recently, growing evidence supports the view that it is also involved in addiction to opiates and other drugs. Theoretical and experimental studies suggest that hippocampal neural-network oscillations at specific frequencies and unit firing patterns reflect information of learning and memory encoding. Here, using multichannel recordings from the hippocampal CA1 area in behaving mice, we investigated the phase correlations between the theta (4-10 Hz) and gamma (40-100 Hz) oscillations, and the timing of spikes modulated by these oscillations. Local field potentials and single unit recordings in the CA1 area of mice receiving chronic morphine treatment revealed that the power of the theta rhythm was strongly increased; at the same time, the theta frequency during different behavioral states shifted markedly, and the characteristic coupling of theta and gamma oscillations was altered. Surprisingly, though the gamma oscillation frequency changed, the power of gamma lacking theta did not. Moreover, the timing of pyramidal cell spikes relative to the theta rhythm and the timing of interneuron spikes relative to the gamma rhythm changed during chronic morphine administration. Furthermore, these responses were impaired by a selective D1/D5 receptor antagonist intra-hippocampus injection. These results indicate that chronic morphine administration induced the changes of ensemble activity in the CA1 area, and these changes were dependent on local dopamine receptor activation.

  6. Layer-specific processing of excitatory signals in CA1 interneurons depends on postsynaptic M₂ muscarinic receptors.

    Science.gov (United States)

    Zheng, Fang; Seeger, Thomas; Nixdorf-Bergweiler, Barbara E; Alzheimer, Christian

    2011-05-02

    The hippocampus receives a diffuse cholinergic innervation which acts on pre- and postsynaptic sites to modulate neurotransmission and excitability of pyramidal cells and interneurons in an intricate fashion. As one missing piece in this puzzle, we explored how muscarinic receptor activation modulates the somatodendritic processing of glutamatergic input in CA1 interneurons. We performed whole-cell recordings from visually identified interneurons of stratum radiatum (SR) and stratum oriens (SO) and examined the effects of the cholinergic agonist carbachol (CCh) on EPSP-like waveforms evoked by brief glutamate pulses onto their proximal dendrites. In SO interneurons, CCh consistently reduced glutamate-induced postsynaptic potentials (GPSPs) in control rat and mice, but not in M₂ muscarinic receptor knockout mice. By contrast, the overwhelming majority of interneurons recorded in SR of control and M₂ receptor-deficient hippocampi exhibited muscarinic enhancement of GPSPs. Interestingly, the non-responding interneurons were strictly confined to the SR subfield closest to the subiculum. Our data suggest that postsynaptic modulation by acetylcholine of excitatory input onto CA1 interneurons occurs in a stratum-specific fashion, which is determined by the absence or presence of M₂ receptors in their (somato-)dendritic compartments. Thus cholinergic projections might be capable of recalibrating synaptic weights in different inhibitory circuits of the CA1 region.

  7. Effects of FK506 on Hippocampal CA1 Cells Following Transient Global Ischemia/Reperfusion in Wistar Rat

    Directory of Open Access Journals (Sweden)

    Zahra-Nadia Sharifi

    2012-01-01

    Full Text Available Transient global cerebral ischemia causes loss of pyramidal cells in CA1 region of hippocampus. In this study, we investigated the neurotrophic effect of the immunosuppressant agent FK506 in rat after global cerebral ischemia. Both common carotid arteries were occluded for 20 minutes followed by reperfusion. In experimental group 1, FK506 (6 mg/kg was given as a single dose exactly at the time of reperfusion. In the second group, FK506 was administered at the beginning of reperfusion, followed by its administration intraperitoneally (IP 6, 24, 48, and 72 hours after reperfusion. FK506 failed to show neurotrophic effects on CA1 region when applied as a single dose of 6 mg/kg. The cell number and size of the CA1 pyramidal cells were increased, also the number of cell death decreased in this region when FK506 was administrated 48 h after reperfusion. This work supports the possible use of FK506 in treatment of ischemic brain damage.

  8. Effects of diazepam on glutamatergic synaptic transmission in the hippocampal CA1 area of rats with traumatic brain injury.

    Science.gov (United States)

    Cao, Lei; Bie, Xiaohua; Huo, Su; Du, Jubao; Liu, Lin; Song, Weiqun

    2014-11-01

    The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after fluid percussion injury. Diazepam can inhibit the hyperexcitability of rat hippocampal neurons after injury, but the mechanism by which it affects excitatory synaptic transmission remains poorly understood. Our results showed that diazepam treatment significantly increased the slope of input-output curves in rat neurons after fluid percussion injury. Diazepam significantly decreased the numbers of spikes evoked by super stimuli in the presence of 15 μmol/L bicuculline, indicating the existence of inhibitory pathways in the injured rat hippocampus. Diazepam effectively increased the paired-pulse facilitation ratio in the hippocampal CA1 region following fluid percussion injury, reduced miniature excitatory postsynaptic potentials, decreased action-potential-dependent glutamine release, and reversed spontaneous glutamine release. These data suggest that diazepam could decrease the fluid percussion injury-induced enhancement of excitatory synaptic transmission in the rat hippocampal CA1 area.

  9. Effects of diazepam on glutamatergic synaptic transmission in the hippocampal CA1 area of rats with traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Lei Cao; Xiaohua Bie; Su Huo; Jubao Du; Lin Liu; Weiqun Song

    2014-01-01

    The activity of the Schaffer collaterals of hippocampal CA3 neurons and hippocampal CA1 neurons has been shown to increase after lfuid percussion injury. Diazepam can inhibit the hy-perexcitability of rat hippocampal neurons after injury, but the mechanism by which it affects excitatory synaptic transmission remains poorly understood. Our results showed that diazepam treatment signiifcantly increased the slope of input-output curves in rat neurons after lfuid per-cussion injury. Diazepam signiifcantly decreased the numbers of spikes evoked by super stimuli in the presence of 15 μmol/L bicuculline, indicating the existence of inhibitory pathways in the injured rat hippocampus. Diazepam effectively increased the paired-pulse facilitation ratio in the hippocampal CA1 region following fluid percussion injury, reduced miniature excitatory postsynaptic potentials, decreased action-potential-dependent glutamine release, and reversed spontaneous glutamine release. These data suggest that diazepam could decrease the lfuid per-cussion injury-induced enhancement of excitatory synaptic transmission in the rat hippocampal CA1 area.

  10. Ongoing intrinsic synchronous activity is required for the functional maturation of CA3-CA1 glutamatergic synapses.

    Science.gov (United States)

    Huupponen, Johanna; Molchanova, Svetlana M; Lauri, Sari E; Taira, Tomi

    2013-11-01

    Fine-tuning of synaptic connectivity during development is guided by intrinsic activity of the immature networks characteristically consisting of intermittent bursts of synchronous activity. However, the role of synchronous versus asynchronous activity in synapse maturation in the brain is unclear. Here, we have pharmacologically prevented generation of synchronous activity in the immature rat CA3-CA1 circuitry in a manner that preserves unitary activity. Long-term desynchronization of the network resulted in weakening of AMPA-receptor-mediated glutamatergic transmission in CA1 pyramidal cells. This weakening was dependent on protein phosphatases and mGluR activity, associated with an increase in the proportion of silent synapses and a decrease in the protein levels of GluA4 suggesting postsynaptic mechanisms of expression. The findings demonstrate that synchronous activity in the immature CA3-CA1 circuitry is critical for the induction and maintenance of glutamatergic synapses and underscores the importance of temporal activity patterns in shaping the synaptic circuitry during development.

  11. Calculating minimum perforating depth with consideration of plastic deformation around well-hole

    Institute of Scientific and Technical Information of China (English)

    LUO Yong

    2007-01-01

    In order to obtain the perforation depth, the three zones with different permeability because of plastic deformation and fluid invasion were studied based on related theories. The study shows that the calculation of perforation depth should take account of not only damaged zone, but also plastic zone, because the plastic zone has much lower permeability. The required minimum perforation depth was obtained by making the solution of elastic/plastic equations, and the factors affecting perforation depth were analyzed accordingly.

  12. Spontaneous Perforation of Pyometra Presented as an Acute Abdomen: A Case Report

    Science.gov (United States)

    Saha, Pradip Kumar; Gupta, Pratiksha; Mehra, Reeti; Goel, Poonam; Huria, Anju

    2008-01-01

    Spontaneous perforation of pyometra is a rare pathologic condition that presents as diffuse peritonitis. This report describes an interesting case of spontaneous uterine perforation that mimicked gut perforation clinically and was finally diagnosed at exploratory laparotomy. Although rare, perforation of pyometra should be kept as one of the differential diagnosis in an elderly woman with an acute abdomen. A high index of suspicion is required to make a correct preoperative diagnosis, which allows early intervention, thus reducing morbidity and mortality. PMID:18324325

  13. Xanthogranulomatous pseudotumor of stomach induced by perforated peptic ulcer mimicking a stromal tumor.

    Science.gov (United States)

    Lai, Hsin-Yi; Chen, Jeon-Hor; Chen, Chi-Kuan; Chen, Yung-Fang; Ho, Yung-Jen; Yang, Mei-Due; Shen, Wu-Chung

    2006-10-01

    Perforation is a serious complication of peptic ulcer disease occurring in 5% of such patients. Occasionally, the perforation may be sealed off by the omentum or the adjacent organs. Sealed perforated ulcer with pseudotumor formation is very rarely encountered. Here we present a case of gastric pseudotumor induced by perforation of a peptic ulcer. The imaging features in a barium sulfate study and computed tomography mimic an intramural tumor of the stomach.

  14. Career Path Descriptions

    CERN Document Server

    Charkiewicz, A

    2000-01-01

    Before the Career Path system, jobs were classified according to grades with general statutory definitions, guided by the "Job Catalogue" which defined 6 evaluation criteria with example illustrations in the form of "typical" job descriptions. Career Paths were given concise statutory definitions necessitating a method of description and evaluation adapted to their new wider-band salary concept. Evaluations were derived from the same 6 criteria but the typical descriptions became unusable. In 1999, a sub-group of the Standing Concertation Committee proposed a new guide for describing Career Paths, adapted to their wider career concept by expanding the 6 evaluation criteria into 9. For each criterion several levels were established tracing the expected evolution of job level profiles and personal competencies over their longer salary ranges. While providing more transparency to supervisors and staff, the Guide's official use would be by services responsible for vacancy notices, Career Path evaluations and rela...

  15. Tortuous path chemical preconcentrator

    Science.gov (United States)

    Manginell, Ronald P.; Lewis, Patrick R.; Adkins, Douglas R.; Wheeler, David R.; Simonson, Robert J.

    2010-09-21

    A non-planar, tortuous path chemical preconcentrator has a high internal surface area having a heatable sorptive coating that can be used to selectively collect and concentrate one or more chemical species of interest from a fluid stream that can be rapidly released as a concentrated plug into an analytical or microanalytical chain for separation and detection. The non-planar chemical preconcentrator comprises a sorptive support structure having a tortuous flow path. The tortuosity provides repeated twists, turns, and bends to the flow, thereby increasing the interfacial contact between sample fluid stream and the sorptive material. The tortuous path also provides more opportunities for desorption and readsorption of volatile species. Further, the thermal efficiency of the tortuous path chemical preconcentrator is comparable or superior to the prior non-planar chemical preconcentrator. Finally, the tortuosity can be varied in different directions to optimize flow rates during the adsorption and desorption phases of operation of the preconcentrator.

  16. Path Optimization Using APSO

    Directory of Open Access Journals (Sweden)

    Deepak Goyal

    2013-07-01

    Full Text Available This paper addresses the malicious node detection and path optimization problem for wireless sensor networks. Malicious node detection in neighborhood is a needed because that node may cause incorrect decisions or energy depletion. In this paper APSO (combination of Artificial bee colony and particular swarm optimization is used to choose an optimized path. Through this improved version we will overcome the disadvantage of local optimal which comes when we use PSO approach.

  17. GABA application to hippocampal CA3 or CA1 stratum lacunosum-moleculare excites an interneuron network.

    Science.gov (United States)

    Perkins, Katherine L

    2002-03-01

    Whole cell voltage-clamp recording and focal application of the neurotransmitter gamma-aminobutyric acid (GABA) were used to investigate the ability of exogenous GABA applied to different locations within the guinea pig hippocampal slice to trigger a giant GABA-mediated postsynaptic current (GPSC) in pyramidal cells. A GPSC reflects the synchronous release of GABA from a group of interneurons. Recordings were done in the presence of 4-aminopyridine (4-AP) and blockers of ionotropic glutamatergic synaptic transmission. Spontaneous GPSCs occurred rhythmically in pyramidal cells under these conditions. Brief focal pressure application of GABA (500 microM; 30-200 ms) to CA3 stratum lacunosum-moleculare (SLM) or to the border between CA3 s. radiatum (SR) and SLM triggered an "all-or-none" GPSC in CA3 and CA1 pyramidal cells that looked like the spontaneous GPSCs. During the refractory period following a spontaneous GPSC, application of GABA could not trigger a GPSC. Both spontaneous GPSCs and GPSCs triggered by exogenous GABA were blocked by suppressing synaptic transmission with high Mg(2+)/low Ca(2+) bath solution. On the other hand, focal application of GABA to CA3 s. oriens (SO) or to proximal SR did not trigger a GPSC in the CA3 pyramidal cell; instead it produced a graded response. Focal application of GABA to regions other than CA3 was also tested. Focal application of GABA to CA1 SLM always triggered a GPSC in the CA3 pyramidal cell. Focal application of GABA within the outer two-thirds of the dentate molecular layer often elicited a GPSC in the CA3 pyramidal cell. In contrast, focal application of GABA to CA1 SO, to CA1 SR, or to the hilus elicited no current response in the CA3 pyramidal cell. These data indicate that the GPSC recorded in pyramidal cells that was triggered by focal GABA application resulted from the synchronous synaptic release of GABA from activated interneurons rather than from the binding of exogenous GABA to receptors on the pyramidal cell

  18. Prolonged enhancement and depression of synaptic transmission in CA1 pyramidal neurons induced by transient forebrain ischemia in vivo.

    Science.gov (United States)

    Gao, T M; Pulsinelli, W A; Xu, Z C

    1998-11-01

    Evoked postsynaptic potentials of CA1 pyramidal neurons in rat hippocampus were studied during 48 h after severe ischemic insult using in vivo intracellular recording and staining techniques. Postischemic CA1 neurons displayed one of three distinct response patterns following contralateral commissural stimulation. At early recirculation times (0-12 h) approximately 50% of neurons exhibited, in addition to the initial excitatory postsynaptic potential, a late depolarizing postsynaptic potential lasting for more than 100 ms. Application of dizocilpine maleate reduced the amplitude of late depolarizing postsynaptic potential by 60%. Other CA1 neurons recorded in this interval failed to develop late depolarizing postsynaptic potentials but showed a modest blunting of initial excitatory postsynaptic potentials (non-late depolarizing postsynaptic potential neuron). The proportion of recorded neurons with late depolarizing postsynaptic potential characteristics increased to more than 70% during 13-24 h after reperfusion. Beyond 24 h reperfusion, approximately 20% of CA neurons exhibited very small excitatory postsynaptic potentials even with maximal stimulus intensity. The slope of the initial excitatory postsynaptic potentials in late depolarizing postsynaptic potential neurons increased to approximately 150% of control values up to 12 h after reperfusion indicating a prolonged enhancement of synaptic transmission. In contrast, the slope of the initial excitatory postsynaptic potentials in non-late depolarizing postsynaptic potential neurons decreased to less than 50% of preischemic values up to 24 h after reperfusion indicating a prolonged depression of synaptic transmission. More late depolarizing postsynaptic potential neurons were located in the medial portion of CA1 zone where neurons are more vulnerable to ischemia whereas more non-late depolarizing postsynaptic potential neurons were located in the lateral portion of CA1 zone where neurons are more resistant to

  19. Perforation into gut by ventriculoperitoneal shunts: A report of two cases and review of the literature

    Directory of Open Access Journals (Sweden)

    Abdul Hai

    2011-01-01

    Full Text Available We report two cases of gastrointestinal perforation by ventriculoperitoneal (VP shunts and review the literature on the topic. The time interval between shunt surgery and detection of bowel perforation is minimum in infants and increases with age. Sigmoid and transverse colon followed by stomach are the most frequent sites of gastrointestinal perforations by VP shunts.

  20. Increased Flap Weight and Decreased Perforator Number Predict Fat Necrosis in DIEP Breast Reconstruction

    Directory of Open Access Journals (Sweden)

    Carolyn L. Mulvey, BS

    2013-05-01

    Conclusions: Flaps with increasing weight have increased risk of fat necrosis. These data suggest that inclusion of more than 1 perforator may decrease odds of fat necrosis in large flaps. Perforator flap breast reconstruction can be performed safely; however, considerations concerning race, body mass index, staging with tissue expanders, perforator number, and flap weight may optimize outcomes.

  1. Effect of ischemic preconditioning on the expression of c-myb in the CA1 region of the gerbil hippocampus after ischemia/reperfusion injury

    Directory of Open Access Journals (Sweden)

    Hui Young Lee

    2016-06-01

    Conclusion: Our results show that a lethal transient ischemia significantly decreased c-myb immunoreactivity in the SP of the CA1 region and that IPC well preserved c-myb immunoreactivity in the SP of the CA1 region. We suggest that the maintenance of c-myb might be related with IPC-mediated neuroprotection after a lethal ischemic insult.

  2. Cloning and characterization of a novel calcium channel toxin-like gene BmCa1 from Chinese scorpion Mesobuthus martensii Karsch.

    Science.gov (United States)

    Zhijian, Cao; Yun, Xie; Chao, Dai; Shunyi, Zhu; Shijin, Yin; Yingliang, Wu; Wenxin, Li

    2006-06-01

    Many studies have been carried on peptides and genes encoding scorpion toxins from the venom of Mesobuthus martensii Karsch (synonym: Buthus martensii Karsch, BmK), such as Na+, K+ and Cl- channel modulators. In this study, a novel calcium channel toxin-like gene BmCa1 was isolated and characterized from the venom of Mesobuthus martensii Karsch. First, a partial cDNA sequence of the Ca2+ channel toxin-like gene was identified by random sequencing method from a venomous gland cDNA library of Mesobuthus martensii Karsch. The full-length sequence of BmCa1 was then obtained by 5'RACE technique. The peptide deduced from BmCa1 precursor nucleotide sequence contains a 27-residue signal peptide and a 37-residue mature peptide. Although BmCa1 and other scorpion toxins are different at the gene and protein primary structure levels, BmCa1 has the same precursor nucleotide organization and cysteine arrangement as that of the first subfamily members of calcium channel scorpion toxins. Genomic DNA sequence of BmCa1 was also cloned by PCR. Sequence analysis showed that BmCa1 gene consists of three exons separated by two introns of 72 bp and 1076 bp in length, respectively. BmCa1 is the first calcium channel toxin-like gene cloned from the venom of Mesobuthus martensii Karsch and potentially represents a novel class of calcium channel toxins in scorpion venoms.

  3. Laparoscopic repair in children with traumatic bladder perforation.

    Science.gov (United States)

    Karadag, Cetin Ali; Tander, Burak; Erginel, Basak; Demirel, Dilek; Bicakci, Unal; Gunaydin, Mithat; Sever, Nihat; Bernay, Ferit; Dokucu, Ali Ihsan

    2016-01-01

    Here, we report two patients with a traumatic intraperitoneal bladder dome rupture repaired by laparoscopic intracorporeal sutures. The first patient was a 3-year old boy was admitted with a history of road accident. He had a traumatic lesion on his lower abdomen and a pelvic fracture. Computed tomography (CT) scan revealed free intraabdominal fluid. The urethragram showed spreading contrast material into the abdominal cavity. Laparoscopic exploration revealed a 3-cm-length perforation at the top of the bladder. The injury was repaired in a two fold fashion. Post-operative follow-up was uneventful. The second case was a 3-year-old boy fell from the second floor of his house on the ground. He had traumatic lesion on his lower abdomen and a pelvic fracture. Due to bloody urine drainage, a cystography was performed and an extravasation from the dome of the bladder into the peritoneum was detected. On laparoscopy, a 3-cm long vertical perforation at the dome of the bladder was found. The perforation was repaired in two layers with intracorporeal suture technique. The post-operative course was uneventful. Laparoscopic repair of traumatic perforation of the bladder dome is a safe, effective and minimally invasive method. The cosmetic outcome is superior.

  4. Laparoscopic repair in children with traumatic bladder perforation

    Directory of Open Access Journals (Sweden)

    Cetin Ali Karadag

    2016-01-01

    Full Text Available Here, we report two patients with a traumatic intraperitoneal bladder dome rupture repaired by laparoscopic intracorporeal sutures. The first patient was a 3-year old boy was admitted with a history of road accident. He had a traumatic lesion on his lower abdomen and a pelvic fracture. Computed tomography (CT scan revealed free intraabdominal fluid. The urethragram showed spreading contrast material into the abdominal cavity. Laparoscopic exploration revealed a 3-cm-length perforation at the top of the bladder. The injury was repaired in a two fold fashion. Post-operative follow-up was uneventful. The second case was a 3-year-old boy fell from the second floor of his house on the ground. He had traumatic lesion on his lower abdomen and a pelvic fracture. Due to bloody urine drainage, a cystography was performed and an extravasation from the dome of the bladder into the peritoneum was detected. On laparoscopy, a 3-cm long vertical perforation at the dome of the bladder was found. The perforation was repaired in two layers with intracorporeal suture technique. The post-operative course was uneventful. Laparoscopic repair of traumatic perforation of the bladder dome is a safe, effective and minimally invasive method. The cosmetic outcome is superior.

  5. Auxetic Perforated Mechanical Metamaterials with Randomly Oriented Cuts.

    Science.gov (United States)

    Grima, Joseph N; Mizzi, Luke; Azzopardi, Keith M; Gatt, Ruben

    2016-01-13

    Perforated systems with quasi-disordered arrays of slits are found to exhibit auxetic characteristics almost as much as their traditional ordered "rotating-squares" counterparts. This provides a highly robust methodology for constructing auxetics that may be used for various practical applications such as skin grafting, where a high degree of precision may not always be achievable.

  6. Primary appendiceal adenocarcinoma of colonic type with perforating peritonitis.

    Directory of Open Access Journals (Sweden)

    Noguch H

    2001-10-01

    Full Text Available Primary adenocarcinoma of the appendix is rare, especially the colonic type. We report a case of appendiceal adenocarcinoma of colonic type associated with perforating peritonitis after aorto-femoral artery bypass surgery. A 79-year-old woman presented with fever and pain in the right lower abdomen. She had undergone aorto-femoral artery bypass surgery due to arteriosclerosis obliterans 6 months earlier. Abdominal ultrasonography and computed tomography showed a suspected pool of fluid surrounding the artificial vessel and a mass lesion in the upper end of the fluid collection. These findings suggested localized peritonitis due to appendiceal perforation. Emergency laparotomy showed a pool of pus around the artificial vessel and inflamed appendix, which adhered to the surrounding tissue. The mass was excised in combination with an ileocaecal resection, followed by an ileocolic anastomosis. The histological diagnosis was moderately differentiated adenocarcinoma of the appendix, colonic type. The tumour had infiltrated and obstructed the lumen of the orifice of the appendix, which may have caused perforation of the appendix. She was examined at regular periodic follow-ups and no evidence of recurrence or metastasis was noted in the 12-month postoperative period. These findings indicate that, in cases of acute appendicitis, especially with perforation, the possibility of appendiceal adenocarcinoma should be considered.

  7. Gastrointestinal Perforation in Neonates: Aetiology and Risk Factors

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    Hyginus Okechukwu Ekwunife

    2013-06-01

    Full Text Available Background: Gastrointestinal perforation (GIP in neonates presents important challenges and mortality can be high. This is a report of recent experience with GIP in neonates in a developing country.Patients and methods: A retrospective review of 16 neonates treated for GIP in a 3 year period.Results: There were 9 males and 7 females, aged 0-28 days (median age =7days. Their weights at presentation ranged from 0.9 - 4.7kg (median =2.6. Five infants were premature. Twelve infants presented more than 72 hours after onset of symptoms. Plain abdominal radiographs showed peumoperitoneum in 9 infants. The cause of perforation was necrotising enterocolitis 6, intestinal obstruction 6, iatrogenic 3 and spontaneous 1. The site of perforation was ileum in 12 infants, stomach in 4 and colon in 4; 4 patients had involvement of more than one site. All the neonates underwent exploratory laparotomy with primary closure ( n=5 , resection and anastomosis( n=6, colostomy (n=3, Ileostomy ( n=2, partial gastrectomy (n=2 ,or gastrojejunostomy ( n=1. Two neonates had multiple procedures. Two very sick preterm babies had an initial peritoneal lavage. Surgical site infection is the commonest postoperative complication occurring in 9 infants. Anaesthesia sepsis and malnutrition is responsible for the seven deaths recorded.Conclusions: Neonatal GIP has multiple aetiologies; NEC is the most common cause. Major mortality risk factors include NEC, multiple perforations, delayed presentation and prematurity.

  8. Oral antibiotics for perforated appendicitis is not recommended

    DEFF Research Database (Denmark)

    Alamili, Mahdi; Gögenur, Ismail; Rosenberg, Jacob

    2010-01-01

    In the majority of surgical departments in Denmark, the postoperative treatment for acute perforated appendicitis comprises three days of intravenous antibiotics. Recently, it has been proposed that such antibiotic regimen should be replaced by orally administered antibiotics. The aim of this pap...

  9. Gastrointestinal Perforation in Neonates: Aetiology and Risk Factors

    Directory of Open Access Journals (Sweden)

    Ekwunife Okechukwu Hyginus

    2013-07-01

    Full Text Available Background: Gastrointestinal perforation (GIP in neonates presents important challenges and mortality can be high. This is a report of recent experience with GIP in neonates in a developing country. Patients and methods: A retrospective review of 16 neonates treated for GIP in a 3 year period. Results: There were 9 males and 7 females, aged 0-28 days (median age =7days. Their weights at presentation ranged from 0.9 - 4.7kg (median =2.6. Five infants were premature. Twelve infants presented more than 72 hours after onset of symptoms. Plain abdominal radiographs showed peumoperitoneum in 9 infants. The cause of perforation was necrotising enterocolitis 6, intestinal obstruction 6, iatrogenic 3 and spontaneous 1. The site of perforation was ileum in 12 infants, stomach in 4 and colon in 4; 4 patients had involvement of more than one site. All the neonates underwent exploratory laparotomy with primary closure ( n=5 , resection and anastomosis( n=6, colostomy (n=3, Ileostomy ( n=2, partial gastrectomy (n=2 ,or gastrojejunostomy ( n=1. Two neonates had multiple procedures. Two very sick preterm babies had an initial peritoneal lavage. Surgical site infection is the commonest postoperative complication occurring in 9 infants. Anaesthesia sepsis and malnutrition is responsible for the seven deaths recorded.Conclusions: Neonatal GIP has multiple aetiologies; NEC is the most common cause. Major mortality risk factors include NEC, multiple perforations, delayed presentation and prematurity.

  10. Spontaneous Uterine Perforation of Pyometra Presenting as Acute Abdomen

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    Toshihiro Kitai

    2014-01-01

    Full Text Available Pyometra is the accumulation of pus in the uterine cavity, and spontaneous perforation of pyometra resulting in generalized diffuse peritonitis is extremely uncommon. We report a rare case of diffuse peritonitis caused by spontaneous perforation of pyometra. A 66-year-old postmenopausal woman with diffuse abdominal pain and vomiting was admitted to our institution. She had a history of mixed connective-tissue disease and had been taking steroids for 20 years. Under a diagnosis of generalized peritonitis secondary to perforation of the gastrointestinal tract or uterus, supravaginal hysterectomy and bilateral salpingo-oophorectomy were performed. Unfortunately, wound dehiscence and infection occurred during the postoperative course, which were exacerbated by her immunocompromised state. Despite intensive care and a course of antibiotics, the patient died of multiple organ failure resulting from sepsis on the 36th postoperative day. Although correct diagnosis, early intervention, and proper treatment can reduce morbidity and mortality of spontaneous perforation of pyometra, if severe infection occurs, this disease can be life threatening for immunocompromised hosts.

  11. Perforated jejunal diverticulitis as a rare cause of acute abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Peters, R.; Grust, A.; Fuerst, G. [Department of Radiology, Heinrich-Heine-University, Duesseldorf (Germany); Gerharz, C.D. [Department of Pathology, Heinrich-Heine-University, Duesseldorf (Germany); Dumon, C. [Department of Surgery, Heinrich-Heine-University, Duesseldorf (Germany)

    1999-09-01

    Jejunal diverticula is rare and in most cases without any symptoms. They become clinically relevant when complications, such as diverticulitis, malabsorption caused by bacterial overgrowth, intestinal hemorrhage, or obstruction, occur. In this case report a case of perforated jejunal diverticulitis is presented and the problems in finding the correct diagnosis are discussed. (orig.) With 3 figs., 13 refs.

  12. Early experience with laparoscopic lavage for perforated diverticulitis

    NARCIS (Netherlands)

    Swank, H.A.; Mulder, I.M.; Hoofwijk, A.G.; Nienhuijs, S.W.; Lange, J.F.; Bemelman, W.A.; Hoeven, J.G. van der

    2013-01-01

    BACKGROUND: Laparoscopic lavage has recently emerged as a promising alternative to sigmoid resection in the treatment of perforated diverticulitis. This study examined an early experience with this technique. METHODS: The files of all patients with complicated diverticulitis were searched in 34 teac

  13. Endoscopic treatment of colorectal perforations--a systematic review

    DEFF Research Database (Denmark)

    Hassan, Mohamed Ali; Thomsen, Christian Øystein; Vilmann, Peter

    2016-01-01

    success rate of 87.8% (standard deviation: ± 13.0%) on average and a median of 92.3% (range: 58.6-100%). The total number of patients needing surgery after attempted clip closure was 30 (14.7%); another four were found to have sealed perforations during surgery. One patient died after clip failure (0...

  14. A Rare Cause of Acute Abdomen: Jejunal Diverticulosis with Perforation

    Directory of Open Access Journals (Sweden)

    Ibrahim Aydin

    2013-01-01

    Full Text Available Jejunal diverticulosis is generally asymptomatic and is associated with high morbidity and mortality secondary to complications, especially in elderly patients. We present a case report of a 74-year-old female patient with jejunal diverticulosis and perforation due to diverticulitis.

  15. Self-organizing nanochannel networks in periodically perforated semiconductor films

    NARCIS (Netherlands)

    Annabattula, R. K.; Onck, P. R.

    2011-01-01

    In this paper we theoretically analyze the mechanism of nanochannel formation by an evolutionary etching process in periodically perforated semiconductor films. The compressive stresses due to lattice mismatch of the epitaxially grown nanoscale films are gradually relaxed; leading to an evolutionary

  16. Spontaneous uterine perforation of pyometra presenting as acute abdomen.

    Science.gov (United States)

    Kitai, Toshihiro; Okuno, Kentaro; Ugaki, Hiromi; Komoto, Yoshiko; Fujimi, Satoshi; Takemura, Masahiko

    2014-01-01

    Pyometra is the accumulation of pus in the uterine cavity, and spontaneous perforation of pyometra resulting in generalized diffuse peritonitis is extremely uncommon. We report a rare case of diffuse peritonitis caused by spontaneous perforation of pyometra. A 66-year-old postmenopausal woman with diffuse abdominal pain and vomiting was admitted to our institution. She had a history of mixed connective-tissue disease and had been taking steroids for 20 years. Under a diagnosis of generalized peritonitis secondary to perforation of the gastrointestinal tract or uterus, supravaginal hysterectomy and bilateral salpingo-oophorectomy were performed. Unfortunately, wound dehiscence and infection occurred during the postoperative course, which were exacerbated by her immunocompromised state. Despite intensive care and a course of antibiotics, the patient died of multiple organ failure resulting from sepsis on the 36th postoperative day. Although correct diagnosis, early intervention, and proper treatment can reduce morbidity and mortality of spontaneous perforation of pyometra, if severe infection occurs, this disease can be life threatening for immunocompromised hosts.

  17. Necrotizing fasciitis caused by perforated appendicitis: a case report.

    Science.gov (United States)

    Hua, Jie; Yao, Le; He, Zhi-Gang; Xu, Bin; Song, Zhen-Shun

    2015-01-01

    Acute appendicitis is one of the most common causes of acute abdominal pain. Accurate diagnosis is often hindered due to various presentations that differ from the typical signs of appendicitis, especially the position of the appendix. A delay in diagnosis or treatment may result in increased risks of complications, such as perforation, which is associated with increased morbidity and mortality rates. Necrotizing fasciitis caused by perforated appendicitis is extremely rare. We herein report a case of 50-year-old man presenting with an appendiceal abscess in local hospital. After ten days of conservative treatment with intravenous antibiotics, the patient complained about pain and swelling of the right lower limb and computed tomography (CT) demonstrated a perforated appendix and gas and fluid collection extending from his retroperitoneal cavity to the subcutaneous layer of his right loin and right lower limb. He was transferred to our hospital and was diagnosed with necrotizing fasciitis caused by perforated appendicitis. Emergency surgery including surgical debridement and appendectomy was performed. However, the patient died of severe sepsis and multiple organ failure two days after the operation. This case represents an unusual complication of a common disease and we should bear in mind that retroperitoneal inflammation and/or abscesses may cause necrotizing fasciitis through lumbar triangles.

  18. Colorectal cancer complicated by perforation. Specific features of surgical tactics

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    S. N. Shchaeva

    2015-01-01

    Full Text Available Objective: to assess the immediate results of surgical interventions for colorectal cancer complicated by perforation.Materials and methods. The immediate results of surgical treatment were retrospectively analyzed in 56 patients with colorectal cancer complicated by perforated colon cancer, who had been treated at Smolensk surgical hospitals in 2001 to 2013. Patients with diastatic perforation of the colon in the presence of decompensated obturation intestinal obstruction of tumor genesis were not included into this investigation.Results. The immediate results of uni- and multistage surgical interventions were analyzed in relation to the extent of peritonitis and the stage of colon cancer. More satisfactory immediate results were observed after multistage surgical treatment. Following these interventions, a fatal outcome of disseminated peritonitis in the presence of performed colorectal cancer was recorded in 8 (53.3 % cases whereas after symptomatic surgery there were 11 (67.8 % deaths. A fatal outcome was noted in 1 case (7.7 % after multistage surgery.Discussion. The results of surgical treatment in the patients with perforated colorectal cancer are directly related to the degree of peritonitis and the choice of surgical tactics.

  19. Numerical Method for Wave Forces Acting on Partially Perforated Caisson

    Institute of Scientific and Technical Information of China (English)

    姜峰; 唐晓成; 金钊; 张莉; 陈洪洲

    2015-01-01

    The perforated caisson is widely applied to practical engineering because of its great advantages in effectively wave energy consumption and cost reduction. The attentions of many scientists were paid to the fluid–structure interaction between wave and perforated caisson studies, but until now, most concerns have been put on theoretical analysis and experimental model set up. In this paper, interaction between the wave and the partial perforated caisson in a 2D numerical wave flume is investigated by means of the renewed SPH algorithm, and the mathematical equations are in the form of SPH numerical approximation based on Navier–Stokes equations. The validity of the SPH mathematical method is examined and the simulated results are compared with the results of theoretical models, meanwhile the complex hydrodynamic characteristics when the water particles flow in or out of a wave absorbing chamber are analyzed and the wave pressure distribution of the perforated caisson is also addressed here. The relationship between the ratio of total horizontal force acting on caisson under regular waves and its influence factors is examined. The data show that the numerical calculation of the ratio of total horizontal force meets the empirical regression equation very well. The simulations of SPH about the wave nonlinearity and breaking are briefly depicted in the paper, suggesting that the advantages and great potentiality of the SPH method is significant compared with traditional methods.

  20. Rectal perforation with an intrauterine device: a case report.

    Science.gov (United States)

    Eichengreen, Courtney; Landwehr, Haley; Goldthwaite, Lisa; Tocce, Kristina

    2015-03-01

    A 27-year-old woman presented for routine examination 1 year after intrauterine device (IUD) placement; strings were not visualized. The device was found to be penetrating through the rectal mucosa. It was removed easily through the rectum during an examination under anesthesia. Perforated IUDs with rectal involvement require thoughtful surgical planning to optimize outcomes.