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  1. NR2B antagonist CP-101,606 inhibits NR2B phosphorylation at tyrosine-1472 and its interactions with Fyn in levodopa-induced dyskinesia rat model.

    PubMed

    Kong, Min; Ba, Maowen; Liu, Chuanyu; Zhang, Yanxiang; Zhang, Hongli; Qiu, Haiyan

    2015-04-01

    The augmented tyrosine phosphorylation of NR2B subunit of N-methyl-d-aspartate receptors (NMDAR) dependent on Fyn kinase has been associated with levodopa (l-dopa)-induced dyskinesia (LID). CP-101,606, one selective NR2B subunit antagonist, can improve dyskinesia. Yet, the accurate action mechanism is less well understood. In the present study, the evidences were investigated. Valid 6-hydroxydopamine-lesioned parkinsonian rats were treated with l-dopa intraperitoneally for 22 days to induce LID rat model. On day 23, rats received either CP-101,606 (0.5mg/kg) or vehicle with each l-dopa dose. On the day of 1, 8, 15, 22, and 23 during l-dopa treatment, we determined abnormal involuntary movements (AIMs) in rats. The levels of NR2B phosphorylation at tyrosine-1472 (pNR2B-Tyr1472) and interactions of NR2B with Fyn in LID rat model were detected by immunoblotting and immunoprecipitation. Results showed that CP-101,606 attenuated l-dopa-induced AIMs. In agreement with behavioral analysis, CP-101,606 reduced the augmented pNR2B-Tyr1472 and its interactions with Fyn triggered during the l-dopa administration in the lesioned striatum of parkinsonian rats. Moreover, CP-101,606 also decreased the level of Ca(2+)/calmodulin-dependent protein kinase II at threonine-286 hyperphosphorylation (pCaMKII-Thr286), which was the downstream signaling amplification molecule of NMDAR overactivation and closely associated with LID. However, the protein level of NR2B and Fyn had no difference under the above conditions. These data indicate that the inhibition of the interactions of NR2B with Fyn and NR2B tyrosine phosphorylation may contribute to the CP-101,606-induced downregulation of NMDAR function and provide benefit for the therapy of LID.

  2. Expression of NR2B in different brain regions and effect of NR2B antagonism on learning deficits after experimental subarachnoid hemorrhage.

    PubMed

    Chen, G; Li, Q; Feng, D; Hu, T; Fang, Q; Wang, Z

    2013-02-12

    Approximately 50% of patients who survived after aneurysmal subarachnoid hemorrhage (SAH) have cognitive or neurobehavioral dysfunction. The mechanisms are not known. NR2B, one of the subunits of N-methyl-d-aspartate (NMDA) receptors, has been proved to be an important factor for synapse function and behavior cognition. Experiment 1 aimed to investigate the timecourse of the NR2B expression in the cortex, hippocampus, and cerebellum after SAH in rats. In experiment 2, we assessed the effect of Ro 25-6981 (a specific NR2B antagonist) on regulation of learning deficits and behavioral activity following SAH. All SAH animals were subjected to injection of autologous blood into the prechiasmatic cistern once on day 0. NR2B was assessed by Western blot analysis and immunohistochemistry. Cognitive and memory changes were investigated in the Morris water maze. As a result, the expression of NR2B was decreased remarkably in SAH groups compared with the control group and the low ebb was on days 1-3. The immunohistochemical staining demonstrated expression of NR2B was present mainly in the neurons in all of the three different regions, such as the cortex, hippocampus, and cerebellum. After Ro 25-6981 intraperitoneal administration, learning deficits induced by SAH was markedly aggravated and clinical behavior scale was also significantly decreased. Our results suggest that NR2B expression is down-regulated in the brain after experimental SAH and NR2B antagonism resulted in augmentation of the development of cognitive dysfunction after SAH.

  3. Memory Enhancement by Targeting Cdk5 Regulation of NR2B

    PubMed Central

    Plattner, Florian; Hernandéz, Adan; Kistler, Tara M.; Pozo, Karine; Zhong, Ping; Yuen, Eunice Y.; Tan, Chunfeng; Hawasli, Ammar H.; Cooke, Sam F.; Nishi, Akinori; Guo, Ailan; Wiederhold, Thorsten; Yan, Zhen; Bibb, James A.

    2014-01-01

    SUMMARY Many psychiatric and neurological disorders are characterized by learning and memory deficits, for which cognitive enhancement is considered a valid treatment strategy. The N-methyl-D-aspartate receptor (NMDAR) is a prime target for the development of cognitive enhancers due to its fundamental role in learning and memory. In particular, the NMDAR subunit NR2B improves synaptic plasticity and memory when over-expressed in neurons. However, NR2B regulation is not well understood and no therapies potentiating NMDAR function have been developed. Here, we show that serine 1116 of NR2B is phosphorylated by cyclin-dependent kinase 5 (Cdk5). Cdk5-dependent NR2B phosphorylation is regulated by neuronal activity and controls the receptor’s cell surface expression. Disrupting NR2B-Cdk5 interaction using a small interfering peptide (siP) increases NR2B surface levels, facilitates synaptic transmission, and improves memory formation in vivo. Our results reveal a novel regulatory mechanism critical to NR2B function that can be targeted for the development of cognitive enhancers. PMID:24607229

  4. Effect of NMDA NR2B antagonist on neuropathic pain in two spinal cord injury models.

    PubMed

    Kim, Youngkyung; Cho, Hwi-young; Ahn, Young Ju; Kim, Junesun; Yoon, Young Wook

    2012-05-01

    N-Methyl-d-aspartate (NMDA) receptors are thought to play an important role in the processes of central sensitization and pathogenesis of neuropathic pain, particularly after spinal cord injury (SCI). NMDA antagonists effectively reduce neuropathic pain, but serious side effects prevent their use as therapeutic drugs. NMDA NR2B antagonists have been reported to effectively reduce inflammatory and neuropathic pain. In this study, we investigated the effects of NR2B antagonists on neuropathic pain and the expression of NR2B in the spinal cord in 2 SCI models. SCI was induced at T12 by a New York University impactor (contusion) or by sectioning of the lateral half of the spinal cord (hemisection). Ifenprodil (100, 200, 500, 1000nmol) and Ro25-6981 (20, 50, 100, 200nmol) were intrathecally injected and behavioral tests were conducted. Ifenprodil increased the paw withdrawal threshold in both models but also produced mild motor depression at higher doses. Ro25-6981 increased the mechanical nociceptive threshold in a dose-dependent manner without motor depression. NR2B expression was significantly increased on both sides at the spinal segments of L1-2 and L4-5 in the hemisection model but did not change in the contusion model. Increased expression of NR2B in the hemisection model was reduced by intrathecal ifenprodil. These results suggest that intrathecal NMDA NR2B antagonist increased the mechanical nociceptive threshold after SCI without motor depression. A selective subtype of NMDA receptor, such as NR2B, may be a more selective target for pain control because NMDA receptors play a crucial role in the development and maintenance of chronic pain.

  5. NR4A1 Knockdown Suppresses Seizure Activity by Regulating Surface Expression of NR2B

    PubMed Central

    Zhang, Yanke; Chen, Guojun; Gao, Baobing; Li, Yunlin; Liang, Shuli; Wang, Xiaofei; Wang, Xuefeng; Zhu, Binglin

    2016-01-01

    Nuclear receptor subfamily 4 group A member 1 (NR4A1), a downstream target of CREB that is a key regulator of epileptogenesis, has been implicated in a variety of biological processes and was previously identified as a seizure-associated molecule. However, the relationship between NR4A1 and epileptogenesis remains unclear. Here, we showed that NR4A1 protein was predominantly expressed in neurons and up-regulated in patients with epilepsy as well as pilocarpine-induced mouse epileptic models. NR4A1 knockdown by lentivirus transfection (lenti-shNR4A1) alleviated seizure severity and prolonged onset latency in mouse models. Moreover, reciprocal coimmunoprecipitation of NR4A1 and NR2B demonstrated their interaction. Furthermore, the expression of p-NR2B (Tyr1472) in epileptic mice and the expression of NR2B in the postsynaptic density (PSD) were significantly reduced in the lenti-shNR4A1 group, indicating that NR4A1 knockdown partly decreased surface NR2B by promoting NR2B internalization. These results are the first to indicate that the expression of NR4A1 in epileptic brain tissues may provide new insights into the molecular mechanisms underlying epilepsy. PMID:27876882

  6. NR2B subunit of the NMDA glutamate receptor regulates appetite in the parabrachial nucleus.

    PubMed

    Wu, Qi; Zheng, Ruimao; Srisai, Dollada; McKnight, G Stanley; Palmiter, Richard D

    2013-09-03

    Diphtheria toxin-mediated, acute ablation of hypothalamic neurons expressing agouti-related protein (AgRP) in adult mice leads to anorexia and starvation within 7 d that is caused by hyperactivity of neurons within the parabrachial nucleus (PBN). Because NMDA glutamate receptors are involved in various synaptic plasticity-based behavioral modifications, we hypothesized that modulation of the NR2A and NR2B subunits of the NMDA receptor in PBN neurons could contribute to the anorexia phenotype. We observed by Western blot analyses that ablation of AgRP neurons results in enhanced expression of NR2B along with a modest suppression of NR2A. Interestingly, systemic administration of LiCl in a critical time window before AgRP neuron ablation abolished the anorectic response. LiCl treatment suppressed NR2B levels in the PBN and ameliorated the local Fos induction that is associated with anorexia. This protective role of LiCl on feeding was blunted in vagotomized mice. Chronic infusion of RO25-6981, a selective NR2B inhibitor, into the PBN recapitulated the role of LiCl in maintaining feeding after AgRP neuron ablation. We suggest that the accumulation of NR2B subunits in the PBN contributes to aphagia in response to AgRP neuron ablation and may be involved in other forms of anorexia.

  7. NR4A1 Knockdown Suppresses Seizure Activity by Regulating Surface Expression of NR2B.

    PubMed

    Zhang, Yanke; Chen, Guojun; Gao, Baobing; Li, Yunlin; Liang, Shuli; Wang, Xiaofei; Wang, Xuefeng; Zhu, Binglin

    2016-11-23

    Nuclear receptor subfamily 4 group A member 1 (NR4A1), a downstream target of CREB that is a key regulator of epileptogenesis, has been implicated in a variety of biological processes and was previously identified as a seizure-associated molecule. However, the relationship between NR4A1 and epileptogenesis remains unclear. Here, we showed that NR4A1 protein was predominantly expressed in neurons and up-regulated in patients with epilepsy as well as pilocarpine-induced mouse epileptic models. NR4A1 knockdown by lentivirus transfection (lenti-shNR4A1) alleviated seizure severity and prolonged onset latency in mouse models. Moreover, reciprocal coimmunoprecipitation of NR4A1 and NR2B demonstrated their interaction. Furthermore, the expression of p-NR2B (Tyr1472) in epileptic mice and the expression of NR2B in the postsynaptic density (PSD) were significantly reduced in the lenti-shNR4A1 group, indicating that NR4A1 knockdown partly decreased surface NR2B by promoting NR2B internalization. These results are the first to indicate that the expression of NR4A1 in epileptic brain tissues may provide new insights into the molecular mechanisms underlying epilepsy.

  8. Molecular level activation insights from a NR2A/NR2B agonist.

    PubMed

    Ieong Tou, Weng; Chang, Su-Sen; Wu, Dongchuan; Lai, Ted Weita; Wang, Yu Tian; Hsu, Chung Y; Chen, Calvin Yu-Chian

    2014-01-01

    N-methyl D-aspartate receptors (NMDARs), a subclass of glutamate receptors have broad actions in neural transmission for major brain functions. Overactivation of NMDARs leading to "excitotoxicity" is the underlying mechanism of neuronal death in a number of neurological diseases, especially stroke. Much research effort has been directed toward developing pharmacological agents to modulate NMDAR actions for treating neurological diseases, in particular stroke. Here, we report that Alliin, a sulfoxide in fresh garlic, exhibits affinity toward NR2A as well as NR2B receptors based on virtual screening. Biological activities of Alliin on these two receptors were confirmed in electrophysiological studies. Ligand-binding site closure, a structural change precluding ion channel opening, was observed with Alliin during 100 ns molecular dynamics simulation. Alliin interactions with NR2A and NR2B suggest that residues E/A413, H485, T690, and Y730 may play important roles in the conformation shift. Activation of NR2A and NR2B by Alliin can be differentiated from that caused by glutamate, the endogenous neurotransmitter. These characteristic molecular features in NR2A and NR2B activation provide insight into structural requirements for future development of novel drugs with selective interaction with NR2A and NR2B for treating neurological diseases, particularly stroke.

  9. The NMDAR subunit NR2B expression is modified in hippocampus after repetitive seizures.

    PubMed

    Auzmendi, J; González, N; Girardi, Elena

    2009-05-01

    NMDA receptor is involved in synaptic plasticity, learning, memory and neurological diseases like epilepsia and it is the major mediator of excitotoxicity. NR2B-containing NMDA receptors may be playing a crucial role in epileptic disorders. In the present study the effect of the convulsant drug 3-mercaptopropionic acid (MP) repetitive administration (4-7 days) on the hippocampal NR2B subunit was studied. A significant decrease in NR2B in the whole hippocampus was observed after MP4 with a tendency to recover to normal values in MP7 by western blot assay. Immunohistochemical studies showed a decrease in several CA1 and CA2/3 strata (21-73%). MP7 showed a reversion of the drop observed at 4 days in stratum oriens, pyramidal cell layer in CA1, CA2/3 and CA1 stratum radiatum. A significant fall in the lacunosum molecular layer of both areas and stratum radiatum of CA2/3 was observed. The immunostaining in MP4 showed a decrease in the granulare layer from dentate gyrus (20%), in hillus (71%) and subicullum (63%) as compared with control and these decreases were similar at MP7 values. Results showed decreases in NR2B subunit expression in different areas following repeated MP-induce seizures, suggesting that NR2B expression is altered depending on the diverse hippocampal input and output signals of each region that could be differently involved in modulating MP-induced hyperactivity.

  10. Tyrosine Phosphorylation of NR2B Contributes to Chronic Migraines via Increased Expression of CGRP in Rats

    PubMed Central

    Liang, Xiping; Wang, Sha; Qin, Guangcheng; Xie, Jingmei; Tan, Ge; Zhou, Jiying; McBride, Devin W.

    2017-01-01

    Tyrosine phosphorylation of NR2B (NR2B-pTyr), a subunit of the N-methyl-D-aspartate (NMDA) receptor, has been reported to develop central sensitization and persistent pain in the spine, but its effect in chronic migraines has not been examined. We hypothesized that tyrosine phosphorylation of NR2B contributes to chronic migraines (CM) through calcitonin gene-related peptide (CGRP) in rats. Ninety-four male Sprague-Dawley rats were subjected to seven inflammatory soup (IS) injections. In a subset of animals, the time course and location of NR2B tyrosine phosphorylation were detected by western blot and immunofluorescence double staining. Another set of animals were given either genistein, vehicle, or genistein and recombinant CGRP. The mechanical threshold was measured, the expressions of NR2B-pTyr, NR2B, and CGRP were quantified using western blot, and nitric oxide (NO) was measured with the nitric acid reductase method. NR2B-pTyr expression, in neurons, peaked at 24 hours after CM. Genistein improved the mechanical threshold and reduced migraine attacks 24 and 72 hours after CM. Tyrosine phosphorylation of NR2B decreased the mechanical threshold and increased migraine attacks via upregulated CGRP expression in the rat model of CM. Thus, tyrosine phosphorylation of NR2B may be a potential therapeutic target for treatment of CM. PMID:28393079

  11. Prenatal stress disturbs hippocampal KIF17 and NR2B in spatial cognition in male offspring.

    PubMed

    Zhao, Depeng; Liu, Dan; Chen, Xueyu; Wang, Kai; Zhang, Ai; Kang, Jiuhong; Zhou, Qian; Duan, Tao

    2013-04-01

    Numerous studies have demonstrated that prenatal stress disturbs the hippocampal-mediated learning and memory processes in offspring. The underlying mechanisms for this effect, however, remain vague. It is well documented that N-methyl-D-aspartate (NMDA) receptors play a pivotal role in learning and memory, which are related to dynamically trafficking and regulating NMDA receptors by their response motor proteins. Over the past few years, increasing numbers of studies have elucidated that hippocampal-mediated learning and memory are regulated by KIF17 (kinesin superfamily motor protein 17), which specifically transports and regulates the NMDA receptor subunit NR2B in hippocampal neurons. The present study shows the influence of prenatal stress on KIF17 and NR2B expression and hippocampal NR2A/NR2B ratio partially reflecting function of KIF17, using mice as models. It was found that prenatal stress significantly decreased the hippocampal KIF17 and NR2B level in offspring at postnatal stages of 3 weeks and 9 weeks. Moreover, hippocampal KIF17 in the prenatally stressed pups continued to be weakened even after serial Morris water maze trainings, but not NR2B. Finally, the synaptic NR2A/NR2B level was upregulated in offspring exposed to prenatal stress, which revealed the dysfunction of KIF17. Thus, we conclude that prenatal stress leads to long-lasting deterioration of the expression and function of hippocampal KIF17 in offspring, which may be related to deficits of spatial cognition caused by prenatal stress. These data underpin the hypotheses that a physiopathology of neurodevelopmental origin in early life leads to defects in learning and memory in later life.

  12. Neuroprotective effect of estrogen: role of nonsynaptic NR2B-containing NMDA receptors.

    PubMed

    Liu, Shui-bing; Zhao, Ming-gao

    2013-04-01

    Excessive activation of N-methyl-D-aspartate receptors (NMDARs) has been implicated in the pathophysiology of chronic neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and Huntington's disease. Some studies reported that NR2A and NR2B play different roles in the central nervous system (CNS). The NR2A subunit is primarily found in the synapses and is required for glutamate-mediated neuronal survival. On the other hand, the NR2B subunit is primarily found in the extrasynaptic sites and is required for glutamate-mediated neuronal death in both in vitro and in vivo experiments. Estrogen is a steroid hormone well known for its widespread effects such as neuroprotection in the brain. Classically, estrogen can bind to two kinds of nuclear receptors, namely, estrogen receptor α (ERα) and estrogen receptor β (ERβ), and produce physiological and neuroprotective effects. Aside from nuclear receptors, estrogen has one membrane receptor, which can either be G-protein-coupled receptor 30 (GPR30), Gq-mER, or ER-X. NMDA exposure clearly promotes NR2B subunit phosphorylation at Ser-1303 and causes neuronal cell death. GPR30 mediates rapid non-genomic effects to protect neurons against injury by inhibiting p-DAPK1 dephosphorylation, which inhibits NR2B subunit phosphorylation at Ser-1303. In addition, NMDA exposure and global ischemia activate the autophagy pathway and induce cell death, which are markedly blocked by the NR2B antagonist Ro 25-6981. Thus, NR2B signaling, autophagy induction and cell death may be closely related. Ro 25-6981 inhibits the dissociation of the NR2B-Beclin-1 signaling complex and delays autophagy in vivo, thus confirming the link between NR2B signaling and autophagy. In short, ERα, ERβ, and GPR30 are involved in the neuroprotection of estrogen in the CNS. Additional research must be conducted to reveal the mechanism of estrogen action fully and to identify better targets for the development of more effective drugs. This

  13. NR2B overexpression leads to the enhancement of specific protein phosphorylation in the brain.

    PubMed

    Li, Chunxia; Zhang, Ning; Hu, Yinghe; Wang, Huimin

    2014-11-07

    n-methyl-d-aspartate receptors (NMDARs) are highly expressed in the central nervous system (CNS) including the cerebral cortex, and it has been found that they contribute significantly to the processes of learning and memory. Dysfunctions of NMDARs are implicated in many neurological disorders. To further investigate the specific role of the NR2B subunit of NMDARs in brain functions, we have examined differences in gene expression in the cerebral cortex between NR2B transgenic mice and their wild-type littermates using the DNA microarray. Total of 179 differentially expressed genes were identified, including genes involved in ion channel activity and/or neurotransmission, signal transduction, structure/cytoskeleton, transcription, and hormone/growth factor activity. Signal pathway analysis has indicated that multiple pathways were involved in this process, especially the Mitogen-activated protein kinases/Extracellular signal-regulated kinases (MAPK/ERK) pathway. The phosphorylation levels of ERK and cAMP response element-binding protein (CREB), and the mRNA levels of CREB target genes (C-Fos and Nr4a1) were significantly upregulated in the cerebral cortices of NR2B transgenic mice compared to their wild-type littermates. Our study suggested that a chronic increase of NMDARs activation by NR2B overexpression in the forebrain may enhance the protein serine/threonine phosphorylation levels of MAPK/ERK-CREB and thereby regulated their signaling pathway.

  14. Chronic Kappa opioid receptor activation modulates NR2B: Implication in treatment resistant depression

    PubMed Central

    Dogra, Shalini; Kumar, Ajeet; Umrao, Deepmala; Sahasrabuddhe, Amogh A.; Yadav, Prem N.

    2016-01-01

    Psychotomimetic and prodepressive effect by kappa opioid receptor (KOR) activation in rodents and human is widely known. Significantly, recent clinical investigations demonstrated the salutary effects of KOR antagonists in patients with treatment resistant depression, indicating essential role of KOR signaling in refractory depression. This study was undertaken to reveal the molecular determinant of KOR mediated depression and antidepressant response of KOR antagonist. We observed that chronic KOR activation by U50488, a selective KOR agonist, significantly increased depression like symptoms (behavioral despair, anhedonia and sociability) in C57BL/6J mice, which were blocked by KOR antagonist norBNI and antidepressant imipramine, but not by fluoxetine or citalopram. Further, chronic KOR activation increased phosphorylation of NR2B subunit of NMDA at tyrosine 1472 (pNR2B NMDA) in the hippocampus, but not in the cortex. Similar to behavioral effects norBNI and imipramine, but not SSRIs, blocked NR2B phosphorylation. Moreover, KOR induced depression like behaviors were reversed by NR2B selective inhibitor Ro 25-6981. Mechanistic studies in primary cultured neurons and brain tissues using genetic and pharmacological approaches revealed that stimulation of KOR modulates several molecular correlates of depression. Thus, these findings elucidate molecular mechanism of KOR signaling in treatment resistant depression like behaviors in mice. PMID:27634008

  15. SRC Inhibition Reduces NR2B Surface Expression and Synaptic Plasticity in the Amygdala

    ERIC Educational Resources Information Center

    Sinai, Laleh; Duffy, Steven; Roder, John C.

    2010-01-01

    The Src protein tyrosine kinase plays a central role in the regulation of N-methyl-d-aspartate receptor (NMDAR) activity by regulating NMDAR subunit 2B (NR2B) surface expression. In the amygdala, NMDA-dependent synaptic plasticity resulting from convergent somatosensory and auditory inputs contributes to emotional memory; however, the role of Src…

  16. Ethanol-withdrawal seizures are controlled by tissue plasminogen activator via modulation of NR2B-containing NMDA receptors.

    PubMed

    Pawlak, Robert; Melchor, Jerry P; Matys, Tomasz; Skrzypiec, Anna E; Strickland, Sidney

    2005-01-11

    Chronic ethanol abuse causes up-regulation of NMDA receptors, which underlies seizures and brain damage upon ethanol withdrawal (EW). Here we show that tissue-plasminogen activator (tPA), a protease implicated in neuronal plasticity and seizures, is induced in the limbic system by chronic ethanol consumption, temporally coinciding with up-regulation of NMDA receptors. tPA interacts with NR2B-containing NMDA receptors and is required for up-regulation of the NR2B subunit in response to ethanol. As a consequence, tPA-deficient mice have reduced NR2B, extracellular signal-regulated kinase 1/2 phosphorylation, and seizures after EW. tPA-mediated facilitation of EW seizures is abolished by NR2B-specific NMDA antagonist ifenprodil. These results indicate that tPA mediates the development of physical dependence on ethanol by regulating NR2B-containing NMDA receptors.

  17. NR2B-deficient mice are more sensitive to the locomotor stimulant and depressant effects of ethanol.

    PubMed

    Badanich, K A; Doremus-Fitzwater, T L; Mulholland, P J; Randall, P K; Delpire, E; Becker, H C

    2011-10-01

    The NR2B subunit of N-methyl d-aspartate glutamate receptors influences pharmacological properties and confers greater sensitivity to the modulatory effects of ethanol. This study examined behavioral responses to acute ethanol in a conditional knockout mouse model that allowed for a delayed genetic deletion of the NR2B subunit to avoid mouse lethality. Mice lacking the NR2B gene (knockout) were produced by mating NR2B[f/f] mice with CAMKIIa-driven tTA transgenic mice and the tetO-CRE transgenic mice. Adult male and female offspring representing each of the resultant genotypes (knockout, CAM, CRE and wildtype mice) were tested for open-field locomotor activity following acute low- and high-dose ethanol challenge as well as loss of righting reflex. Findings indicate that male and female mice lacking the NR2B subunit exhibited greater overall activity in comparison to other genotypes during the baseline locomotor activity test. NR2B knockout mice exhibited an exaggerated stimulant response to 1.5 g/kg (i.p.) and an exaggerated depressant response to 3.0 g/kg (i.p.) ethanol challenge. In addition, NR2B knockout mice slept longer following a high dose of ethanol (4.0 g/kg, i.p.). To evaluate pharmacokinetics, clearance rates of ethanol (1.5, 4.0 g/kg, i.p.) were measured and showed that female NR2B knockouts had a faster rate of metabolism only at the higher ethanol dose. Western blot analyses confirmed significant reduction in NR2B expression in the forebrain of knockout mice. Collectively, these data indicate that the NR2B subunit of the N-methyl d-aspartate glutamate receptor is involved in regulating low-dose stimulant effects of ethanol and the depressant/hypnotic effects of ethanol.

  18. Influences of NR2B-containing NMDA receptors knockdown on neural activity in hippocampal newborn neurons.

    PubMed

    Li, Zhi-jun; Zhang, Hui-wen; Tang, Na

    2013-08-01

    Adult-born neurons undergo a transient period of plasticity during their integration into the neural circuit. This transient plasticity may involve NMDA receptors containing NR2B, the major subunit expressed at early developmental stages. The main objective of the present study was to investigate the effects of NR2B gene knockdown on the functional integration of the adult-born granule cells generated from the subgranule zone (SGZ) in the hippocampus. The small interfering RNA (siRNA) was used to knock down the NR2B gene in the adult-born hippocampal neurons. In the functional integration test, the mice were exposed to a novel environment (open field arena), and the expression of c-fos was immunohistochemically detected in the hippocampus. After exposure to the novel environment, siRNA-NR2B mice were significantly different from control mice in either the number of squares or the number of rears they crossed, showing decreased horizontal and vertical activity (P<0.05). Moreover, the c-fos expression was increased in both control and siRNA-NR2B mice after open field test. But, it was significantly lower in siRNA-NR2B neurons than in control neurons. It was concluded that the neural activity of newborn neurons is regulated by their own NR2B-containing NMDA glutamate receptors during a short, critical period after neuronal birth.

  19. IGF-1-Involved Negative Feedback of NR2B NMDA Subunits Protects Cultured Hippocampal Neurons Against NMDA-Induced Excitotoxicity.

    PubMed

    Li, Yun; Sun, Wei; Han, Song; Li, Jianing; Ding, Shu; Wang, Wei; Yin, Yanling

    2017-01-01

    Insulin-like growth factor 1 (IGF-1) is a multifunctional protein involved in neuronal polarity and axonal guidance. In our previous study, it was discovered that IGF-1 alleviated 50-μM NMDA-induced excitotoxicity against neuronal autophagy via depression of NR2B p-Ser1303 activation. However, it was found that NMDA at a higher dose did not cause neuronal autophagy. And, the performance of IGF-1 under severe excitotoxicity still needs to be clarified. In this study, we observed that IGF-1 can salvage the hippocampal neurons in an autophagy-independent manner after 150-μM NMDA exposure using thiazolyl blue tetrazolium bromide (MTT), lactate dehydrogenase (LDH), Western blot assay, and transmission electron microscopy. In addition, over-activation of post-synaptic NMDARs was found with the whole-cell patch clamp recording method. In order to explore whether there is a positive feedback way for post-synaptic NMDARs and the different pathway caused by 150 μM NMDA, the phosphorylation level of Fyn and the phosphorylation site of NR2B were investigated. It was observed that NR2B p-Tyr1472 was increased by the activation of Fyn after 150-μM NMDA exposure. When the neutralizing antibody against NR2B p-Ser1303 was added into the medium, both the activations of Fyn and NR2B p-Tyr1472 were blocked, suggesting NR2B p-Ser1303 may be the initial step of NMDA-induced excitotoxicity. In addition, since IGF-1 can block the initial step of NR2B activation, its effect is concluded to continue with the development of excitotoxicity. Overall, this study strongly indicates that the relationship between different phosphorylation sites of NR2B should be laid more emphasis on, which may be a vital target for the NR2B-involved excitotoxicity.

  20. Effects of chronic NMDA-NR2b inhibition in the median eminence of the reproductive senescent female rat.

    PubMed

    Kermath, B A; Riha, P D; Sajjad, A; Gore, A C

    2013-10-01

    Gonadotrophin-releasing hormone (GnRH) neurones of the hypothalamic-pituitary-gonadal (HPG) axis drive reproductive function and undergo age-related decreases in activation during the transition to reproductive senescence. Decreased GnRH secretion from the median eminence (ME) partially arises from attenuated glutamatergic signalling via the NMDA receptor (NMDAR) and may be a result of changing NMDAR stoichiometry to favour NR2b over NR2a subunit expression with ageing. We have previously shown that the systemic inhibition of NR2b-containing receptors with ifenprodil, an NR2b-specific antagonist, stimulates parameters of luteinising hormone (used as a proxy for GnRH) release in both young and middle-aged females. In the present study, we chronically administered ifenprodil, an NR2b-specific antagonist, at the site of GnRH terminals in the ME or at GnRH perikarya in the preoptic area, in reproductively senescent middle-aged female rats, aiming to determine whether NR2b antagonism could restore aspects of reproductive functionality. Effects on oestrous cyclicity, serum hormones, and protein expression of GnRH, NR2b and phosphorylated NR2b (Tyr-1472) in the ME were measured. Chronic ifenprodil treatment in the ME (but not the preoptic area) altered oestrous cyclicity by increasing the percentage of days spent in pro-oestrus. This was accompanied by increased GnRH fluorescence intensity in the external ME zone and a greater proportion of GnRH terminals that co-labelled with pNR2b with treatment. We also observed changes in the relationships between protein immunofluorescence, serum hormone levels and other aspects of reproductive physiology in acyclic females, as revealed by bionetwork analysis. Together, these data support the hypothesis that NMDAR-NR2b expression and phosphorylation state play a role in reproductive senescence and highlight the ME as a major player in reproductive ageing.

  1. Discovery of 3-Substituted Aminocyclopentanes as Potent and Orally Bioavailable NR2B Subtype-Selective NMDA Antagonists

    PubMed Central

    2011-01-01

    A series of 3-substituted aminocyclopentanes has been identified as highly potent and selective NR2B receptor antagonists. Incorporation of a 1,2,4-oxadiazole linker and substitution of the pendant phenyl ring led to the discovery of orally bioavailable analogues that showed efficient NR2B receptor occupancy in rats. Unlike nonselective NMDA antagonists, the NR2B-selective antagonist 22 showed no adverse affects on motor coordination in the rotarod assay at high dose. Compound 22 was efficacious following oral administration in a spinal nerve ligation model of neuropathic pain and in an acute model of Parkinson’s disease in a dose dependent manner. PMID:22816022

  2. NR2B receptor blockade inhibits pain-related sensitization of amygdala neurons.

    PubMed

    Ji, Guangchen; Horváth, Csilla; Neugebauer, Volker

    2009-04-28

    Pain-related sensitization and synaptic plasticity in the central nucleus of the amygdala (CeA) depend on the endogenous activation of NMDA receptors and phosphorylation of the NR1 subunit through a PKA-dependent mechanism. Functional NMDA receptors are heteromeric assemblies of NR1 with NR2A-D or NR3A, B subunits. NMDA receptors composed of NR1 and NR2B subunits have been implicated in neuroplasticity and are present in the CeA. Here we used a selective NR2B antagonist (Ro-256981) to determine the contribution of NR2B-containing NMDA receptors to pain-related sensitization of CeA neurons. Extracellular single-unit recordings were made from CeA neurons in anesthetized adult male rats before and during the development of an acute arthritis. Arthritis was induced in one knee joint by intraarticular injections of kaolin and carrageenan. Brief (15 s) mechanical stimuli of innocuous (100-500 g/30 mm2) and noxious (1000-2000 g/30 mm2) intensity were applied to the knee and other parts of the body. In agreement with our previous studies, all CeA neurons developed increased background and evoked activity after arthritis induction. Ro-256981 (1, 10 and 100 muM; 15 min each) was administered into the CeA by microdialysis 5-6 h postinduction of arthritis. Ro-256981 concentration-dependently decreased evoked responses, but not background activity. This pattern of effect is different from that of an NMDA receptor antagonist (AP5) in our previous studies. AP5 (100 microM - 5 mM) inhibited background activity and evoked responses. The differential effects of AP5 and Ro-256981 may suggest that NMDA receptors containing the NR2B subunit are important but not sole contributors to pain-related changes of CeA neurons.

  3. Reduction of inflammatory pain in female rats after NR2B NMDA cortical antagonism.

    PubMed

    Vasquez, Carol; Sánchez, Melany; Herrera, Jairo; Quintero, Gabriel

    2012-05-01

    Studies have shown that N-methyl-D-aspartate (NMDA) receptors play a critical role in pain processing at different levels of the central nervous system. In this study, we used female adult Wistar rats to examine the effects of antagonizing the NR2B subunit of the NMDA receptor in phasic and tonic pain processes. All the rats underwent stereotaxic surgery for cortical cannula implantation and after at least one week of recovery, rats performed behavioral tests. For evaluating the effects of drugs on motor coordination rats were tested in the rotarod apparatus. Moreover, rats were evaluated in the paw withdrawal latency (PWL) to a noxious thermal stimulus. Furthermore, rats were tested in the formalin-pain test. Rats that received the NR2B antagonist Ro 25-6981 before and after formalin injection showed significantly reduced pain responses in the formalin test, as compared with female control rats (p<0.05). In contrast, no differences among groups were found in the phasic pain test (Hargreaves) and the rotarod test. Taken together, these results suggest that cortical antagonism of the NR2B subunit of NMDA receptors is able to reduce inflammatory pain levels not only before, but after the formalin injection in females at different phases of the estrous cycle.

  4. Hippocampal NR2B-containing NMDA receptors enhance long-term potentiation in rats with chronic visceral pain.

    PubMed

    Chen, Yu; Chen, Ai-qin; Luo, Xiao-qing; Guo, Li-xia; Tang, Ying; Bao, Cheng-jia; Lin, Ling; Lin, Chun

    2014-06-27

    Pain and learning memory have striking similarities in synaptic plasticity. Activation of the N-methyl-D-aspartic acid receptors 2B subunits (NR2B-NMDAs) is responsible for the hippocampal LTP in memory formation. In our previous studies, we found the significant enhancement of CA1 hippocampal long-term potentiation (LTP) induced by high-frequency stimulation (HFS) in rats with chronic visceral pain. However, it is unclear whether the NR2B-NMDAs are required for the LTP in chronic visceral pain. In this study, a rat model with irritable bowel syndrome (IBS) was established by colorectal distention (CRD). The sensitivity of visceral pain and HFS-induced LTP at SC-CA1 synapses were significantly enhanced in IBS-like rats (p<0.05). In addition, hippocampal NR2B protein levels significantly increased in IBS-like rats (p<0.05). To test whether NR2B-NMDAs are responsible for the LTP, effects of Ro 25-6981, a selective antagonist of NR2B-NMDAs, on field potential in CA1 region were investigated in vitro. Our results demonstrated that Ro 25-6981 dose-dependently inhibited the facilitation of CA1 LTP in IBS-like rats. The plausible activation mechanism of hippocampal NR2B-NMDAs in the LTP enhancement was further explored. Western blot data indicated that expression of tyrosine phosphorylated NR2B protein in hippocampus significantly enhanced in IBS-like rats. Accordingly, genistein, a specific inhibitor of tyrosine kinases, dose-dependently blocked the facilitation of hippocampal LTP in IBS-like rats. Furthermore, EMG data revealed that intra-hippocampal injection of Ro 25-6981 dose-dependently attenuated the visceral hypersensitivity. In conclusion, hippocampal NR2B-NMDAs are responsible for the facilitation of CA1 LTP via tyrosine phosphorylation, which leads to visceral hypersensitivity.

  5. Immunolocalization of CaMKII and NR2B in hippocampal subregions of rat during postnatal development.

    PubMed

    Liu, Weiya; Chang, Lirong; Song, Yizhi; Gao, Xianghong; Ling, Wei; Lu, Tao; Zhang, Yali; Wu, Yan

    2013-04-01

    Although the expression of CaMKII and synaptic-associated proteins has been widely studied, the temporospatial distribution of CaMKII and NMDAR subunits in different hippocampal subregions during postnatal development still lacks detailed information. In this study, we used immunofluorescent staining to assess CaMKII and NR2B expressions and the relationship between them in CA1, CA3, and DG of rat hippocampus on postnatal (P) days: P0, P4, P7, P10, P14, P21, P28, and P56. The results showed that from P0 to P56, CaMKII expression increased gradually, while NR2B expression decreased gradually, and the time points of their expression peak differed in CA1, CA3, and DG during postnatal development. Although the expression of CaMKII was negatively correlated with NR2B in CA1 and DG, the coexpression of CaMKII with NR2B existed in CA1, CA3, and DG during postnatal development. Interestingly, after P21, CaMKII expression and the coexpression of CaMKII with NR2B became obvious in the Stratum lucidum of CA3. The specific temporospatial distribution pattern of CaMKII with NR2B might be related to the different physiological functions during postnatal development. Discovery of the alteration of the relationship between expression of CaMKII and NMDAR subunits may be helpful for understanding mechanisms and therapy of neurodegenerative diseases.

  6. The role of NR2B containing NMDA receptor in place preference conditioned with morphine and natural reinforcers in rats.

    PubMed

    Ma, Yao-Ying; Guo, Chang-Yong; Yu, Peng; Lee, David Yue-Wei; Han, Ji-Sheng; Cui, Cai-Lian

    2006-08-01

    It has been reported that N-methyl-D-aspartate (NMDA) receptor is implicated in drug addiction and antagonists of the NMDA receptor complex can inhibit the development and expression of conditioned place preference (CPP) induced by several addictive drugs, implying that this class of compounds might be considered as candidate for the treatment of substance abuse. To explore this possibility, it is important to evaluate whether the inhibitory effect of NMDA receptor antagonists would be confined to behaviors produced by drugs of abuse only, but not by natural reinforcers. According to the quantitative changes of NMDA receptor subunits, including NR1, NR2A, and NR2B, induced by diverse types of reinforcers, we chose NR2B subunit as the target of research. Experimental results showed that (1) an augmented expression of NR2B subunit was revealed by Western blotting in the nucleus accumbens (NAc) and the hippocampus in rats with CPP induced by morphine, but not by natural rewards such as food, novel environment and social interaction. (2) Ifenprodil, an antagonist highly selective for NR2B subunit of the NMDA receptor, produced a dose-dependent reduction in CPP induced by morphine and novel environment, but not that by food consumption and social interaction. Taking together, these findings suggested that NR2B containing NMDA receptor may be more involved with morphine reward rather than natural rewards, and that antagonism of NR2B may have a potential for the treatment of morphine abuse.

  7. Role for the NR2B Subunit of the NMDA Receptor in Mediating Light Input to the Circadian System

    PubMed Central

    Wang, LM; Schroeder, A; Loh, D; Smith, D; Lin, K; Han, JH; Michel, S; Hummer, DL; Ehlen, JC; Albers, HE; Colwell, CS

    2008-01-01

    Light information reaches the suprachiasmatic nucleus (SCN) through a subpopulation of retinal ganglion cells that utilize glutamate as a neurotransmitter. A variety of evidence suggests that the release of glutamate then activates N-methyl-Daspartate (NMDA) receptors within the SCN and triggers a signaling cascade that ultimately leads to phase shifts in the circadian system. In this study, we first sought to explore the role of the NR2B subunit in mediating the effects of light on the circadian system. We found that localized microinjection of the NR2B subunit antagonist ifenprodil into the SCN region inhibits the magnitude of light-induced phase shifts of the circadian rhythm in wheel-running activity. Next, we found that the NR2B message and levels of phospho-NR2B levels vary with time of day in SCN tissue using semi-quantitative real-time PCR and Western blot analysis, respectively. Functionally, we found that blocking the NR2B subunit with ifenprodil significantly reduced the magnitude of NMDA currents recorded in SCN neurons. Ifenprodil also significantly reduced the magnitude of NMDA-induced calcium changes in SCN cells. Together, these results demonstrate that the NR2B subunit is an important component of NMDA receptor mediated responses within SCN neurons and that this subunit contributes to light-induced phase shifts of the mammalian circadian system. PMID:18380671

  8. SETDB1 HISTONE METHYLTRANSFERASE REGULATES MOOD-RELATED BEHAVIORS AND EXPRESSION OF THE NMDA RECEPTOR SUBUNIT NR2B

    PubMed Central

    Jiang, Yan; Jakovcevski, Mira; Bharadwaj, Rahul; Connor, Caroline; Schroeder, Frederick A.; Lin, Cong L.; Straubhaar, Juerg; Martin, Gilles; Akbarian, Schahram

    2010-01-01

    Histone methyltransferases specific for the histone H3-lysine 9 (H3K9) residue, including Setdb1 (Set domain, bifurcated 1)/Eset/Kmt1e are associated with repressive chromatin remodeling and expressed in adult brain, but potential effects on neuronal function and behavior remain unexplored. Here, we report that transgenic mice with increased Setdb1 expression in adult forebrain neurons show antidepressant-like phenotypes in behavioral paradigms for anhedonia, despair and learned helplessness. Chromatin immunoprecipitation in conjunction with DNA tiling arrays (ChIP-chip) revealed that genomic occupancies of neuronal Setdb1 are limited to less than 1% of annotated genes, which include the NMDA receptor subunit NR2B/Grin2B and other ionotropic glutamate receptor genes. Chromatin conformation capture (“3C”) and Setdb1-ChIP revealed a loop formation tethering the NR2B/Grin2b promoter to the Setdb1 target site positioned 30Kb downstream of the transcription start site. In hippocampus and ventral striatum, two key structures in the neuronal circuitry regulating mood-related behaviors, Setdb1-mediated repressive histone methylation at NR2B/Grin2b was associated with decreased NR2B expression and EPSP insensitivity to pharmacological blockade of NR2B, and accelerated NMDA receptor desensitization consistent with a shift in NR2A/B subunit ratios. In wildtype mice, systemic treatment with the NR2B antagonist, Ro-256981, and hippocampal siRNA-mediated NR2B/Grin2b knockdown, resulted in behavioral changes similar to those elicited by the Setdb1 transgene. Together, these findings point to a role for neuronal Setdb1 in the regulation of affective and motivational behaviors through repressive chromatin remodeling at a select set of target genes, resulting in altered NMDA receptor subunit composition and other molecular adaptations. PMID:20505083

  9. Kalirin binds the NR2B subunit of the NMDA receptor, altering its synaptic localization and function

    PubMed Central

    Kiraly, Drew D.; Lemtiri-Chlieh, Fouad; Levine, Eric S.; Mains, Richard E.; Eipper, Betty A.

    2011-01-01

    The ability of dendritic spines to change size and shape rapidly is critical in modulating synaptic strength; these morphological changes are dependent upon rearrangements of the actin cytoskeleton. Kalirin-7 (Kal7), a Rho guanine nucleotide exchange factor (GEF) localized to the postsynaptic density (PSD), modulates dendritic spine morphology in vitro and in vivo. Kal7 activates Rac and interacts with several PSD proteins including PSD-95, DISC-1, AF-6 and Arf6. Mice genetically lacking Kal7 (Kal7KO) exhibit deficient hippocampal LTP as well as behavioral abnormalities in models of addiction and learning. Purified PSDs from Kal7KO mice contain diminished levels of NR2B, an NMDA receptor subunit that plays a critical role in LTP induction. Here we demonstrate that Kal7KO animals have decreased levels of NR2B-dependent NMDA receptor currents in cortical pyramidal neurons as well as a specific deficit in cell-surface expression of NR2B. Additionally, we demonstrate that the genotypic differences in conditioned place preference and passive avoidance learning seen in Kal7KO mice are abrogated when animals are treated with an NR2B-specific antagonist during conditioning. Finally, we identify a stable interaction between the pleckstrin homology domain of Kal7 and the juxtamembrane region of NR2B preceding its cytosolic C-terminal domain. Binding of NR2B to a protein that modulates the actin cytoskeleton is important, as NMDA receptors require actin integrity for synaptic localization and function. These studies demonstrate a novel and functionally important interaction between the NR2B subunit of the NMDA receptor and Kalirin, proteins known to be essential for normal synaptic plasticity. PMID:21880917

  10. Kalirin binds the NR2B subunit of the NMDA receptor, altering its synaptic localization and function.

    PubMed

    Kiraly, Drew D; Lemtiri-Chlieh, Fouad; Levine, Eric S; Mains, Richard E; Eipper, Betty A

    2011-08-31

    The ability of dendritic spines to change size and shape rapidly is critical in modulating synaptic strength; these morphological changes are dependent upon rearrangements of the actin cytoskeleton. Kalirin-7 (Kal7), a Rho guanine nucleotide exchange factor localized to the postsynaptic density (PSD), modulates dendritic spine morphology in vitro and in vivo. Kal7 activates Rac and interacts with several PSD proteins, including PSD-95, DISC-1, AF-6, and Arf6. Mice genetically lacking Kal7 (Kal7(KO)) exhibit deficient hippocampal long-term potentiation (LTP) as well as behavioral abnormalities in models of addiction and learning. Purified PSDs from Kal7(KO) mice contain diminished levels of NR2B, an NMDA receptor subunit that plays a critical role in LTP induction. Here we demonstrate that Kal7(KO) animals have decreased levels of NR2B-dependent NMDA receptor currents in cortical pyramidal neurons as well as a specific deficit in cell surface expression of NR2B. Additionally, we demonstrate that the genotypic differences in conditioned place preference and passive avoidance learning seen in Kal7(KO) mice are abrogated when animals are treated with an NR2B-specific antagonist during conditioning. Finally, we identify a stable interaction between the pleckstrin homology domain of Kal7 and the juxtamembrane region of NR2B preceding its cytosolic C-terminal domain. Binding of NR2B to a protein that modulates the actin cytoskeleton is important, as NMDA receptors require actin integrity for synaptic localization and function. These studies demonstrate a novel and functionally important interaction between the NR2B subunit of the NMDA receptor and Kalirin, proteins known to be essential for normal synaptic plasticity.

  11. Arcuate Src activation-induced phosphorylation of NR2B NMDA subunit contributes to inflammatory pain in rats.

    PubMed

    Xu, Longsheng; Pan, Yanyan; Zhu, Qi; Gong, Shan; Tao, Jin; Xu, Guang-Yin; Jiang, Xinghong

    2012-12-01

    The tyrosine kinases of Src family play an important role in the central sensitization following peripheral inflammation. However, whether the Src family in the arcuate nucleus (ARC) of mediobasal hypothalamus is involved in central sensitization remains unknown. The aim of this study was to investigate the role and mechanisms of tyrosine kinases of Src family in N-methyl-d-aspartate (NMDA) receptor activity in the ARC following peripheral inflammation. Peripheral inflammation was induced by unilateral injection of complete Freund's adjuvant (CFA) into rat hindpaw. The neuronal activities of the ARC were recorded using electrophysiological field recording from the in vitro mediobasal hypothalamic slices from control and CFA rats. Expression of total and phosphorylated Src and NR2B subunit protein was analyzed by Western blot and immuoprecipitation. Our results showed that CFA injection resulted in an increase in mechanical and thermal sensitivity, which was partially blocked by neonatal monosodium glutamate treatment. CFA injection also enhanced spontaneous firings of ARC neurons, which were reversed by the NMDA receptor NR2B subunit specific antagonist Ro25-6981 and by PP2, an Src family tyrosine kinase inhibitor. In addition, peripheral inflammation enhanced Src phosphorylation and NMDA receptor NR2B subunit phosphorylation without alteration of total NR2B subunit expression in the ARC. Peripheral inflammation also increased the association of NR2B protein with p-Src protein in the ARC. Administration of PP2 blocked the upregulation of NR2B phosphorylation induced by CFA injection. Taken together, our present results suggest that the arcuate Src activation-induced tyrosine phosphorylation of NR2B NMDA subunit may contribute to inflammatory pain.

  12. Early chronic blockade of NR2B subunits and transient activation of NMDA receptors modulate LTP in mouse auditory cortex.

    PubMed

    Mao, Yuting; Zang, Shaoyun; Zhang, Jiping; Sun, Xinde

    2006-02-16

    In the auditory cortex, the properties of NMDA receptors depend primarily on the ratio of NR2A and NR2B subunits. NR2B subunit expression is high at the beginning of critical period and lower in adulthood. Because NMDA receptors are crucial in triggering long-term potentiation (LTP) and long-term depression, developmental or experience-dependent modification of NMDAR subunit composition is likely to influence synaptic plasticity. To examine how NMDA subunit change during postnatal development affect the adult synaptic plasticity, we employed chronic ifenprodil blockade of NR2B subunits and analyzed evoked field potentials in adult C57BL/6 mice auditory cortex (AC). We found that chronic loss of NR2B activity led to a decline in LTP magnitude in the AC of adult mice. Adding NMDA to the artificial cerebrospinal fluid (ACSF) in blocked mice had the opposite effect, producing LTP magnitudes at or exceeding those found in treated or untreated animals. These results suggest that, even in adulthood when NR2B expression is downregulated, these receptor subunits play an important role in experience-dependent plasticity of mouse auditory cortex. Blockade from P60 did not result in any decrease of LTP amplitude, suggesting that chronic block in postnatal period may permanently affect cortical circuits so that they cannot produce significant LTP in adulthood.

  13. NMDA receptor NR2B subunits contribute to PTZ-kindling-induced hippocampal astrocytosis and oxidative stress.

    PubMed

    Zhu, Xinjian; Dong, Jingde; Shen, Kai; Bai, Ying; Zhang, Yuan; Lv, Xuan; Chao, Jie; Yao, Honghong

    2015-05-01

    The N-methyl-d-aspartate (NMDA) receptor plays an important role in the pathophysiology of several neurological diseases, including epilepsy. The present study investigated the effect of NMDA receptor NR2B subunits on pentylenetetrazole (PTZ)-kindling-induced pathological and biochemical events in mice. Our results showed that PTZ-kindling up-regulates the expression of NMDA receptor NR2B subunits in the hippocampus and that kindled mice were characterized by significant astrocytosis and neuron loss in the hippocampus. Oxidative stress, including excessive malondialdehyde (MDA) production and decreased enzymatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), were detected in the hippocampus after the mice were fully kindled. Additionally, expression of brain-derived neurotrophic factor (BDNF) in the hippocampus was found to be up-regulated in PTZ-kindled mice. However, selectively blocking NMDA receptor NR2B subunits by ifenprodil significantly suppressed PTZ-kindling-induced hippocampal astrocytosis, oxidative stress and neuron loss. Furthermore, blocking NMDA receptor NR2B subunits also abolished PTZ-kindling-induced BDNF expression. These results indicate that NMDA receptor NR2B subunits contribute to epilepsy-associated pathological and biochemical events, including hippocampal astrocytosis, oxidative stress and neuron loss, and these events might be correlated with up-regulation of BDNF expression.

  14. Negative Allosteric Modulators Selective for The NR2B Subtype of The NMDA Receptor Impair Cognition in Multiple Domains.

    PubMed

    Weed, Michael R; Bookbinder, Mark; Polino, Joseph; Keavy, Deborah; Cardinal, Rudolf N; Simmermacher-Mayer, Jean; Cometa, Fu-ni L; King, Dalton; Thangathirupathy, Srinivasan; Macor, John E; Bristow, Linda J

    2016-01-01

    Antidepressant activity of N-methyl-D-aspartate (NMDA) receptor antagonists and negative allosteric modulators (NAMs) has led to increased investigation of their behavioral pharmacology. NMDA antagonists, such as ketamine, impair cognition in multiple species and in multiple cognitive domains. However, studies with NR2B subtype-selective NAMs have reported mixed results in rodents including increased impulsivity, no effect on cognition, impairment or even improvement of some cognitive tasks. To date, the effects of NR2B-selective NAMs on cognitive tests have not been reported in nonhuman primates. The current study evaluated two selective NR2B NAMs, CP101,606 and BMT-108908, along with the nonselective NMDA antagonists, ketamine and AZD6765, in the nonhuman primate Cambridge Neuropsychological Test Automated Battery (CANTAB) list-based delayed match to sample (list-DMS) task. Ketamine and the two NMDA NR2B NAMs produced selective impairments in memory in the list-DMS task. AZD6765 impaired performance in a non-specific manner. In a separate cohort, CP101,606 impaired performance of the nonhuman primate CANTAB visuo-spatial Paired Associates Learning (vsPAL) task with a selective impairment at more difficult conditions. The results of these studies clearly show that systemic administration of a selective NR2B NAM can cause transient cognitive impairment in multiple cognitive domains.

  15. Co-activation of NR2A and NR2B subunits induces resistance to fear extinction.

    PubMed

    Leaderbrand, Katherine; Corcoran, Kevin A; Radulovic, Jelena

    2014-09-01

    Unpredictable stress is known to profoundly enhance susceptibility to fear and anxiety while reducing the ability to extinguish fear when threat is no longer present. Accordingly, partial aversive reinforcement, via random exposure to footshocks, induces fear that is resistant to extinction. Here we sought to determine the hippocampal mechanisms underlying susceptibility versus resistance to context fear extinction as a result of continuous (CR) and partial (PR) reinforcement, respectively. We focused on N-methyl-D-aspartate receptor (NMDAR) subunits 2A and B (NR2A and NR2B) as well as their downstream signaling effector, extracellular signal-regulated kinase (ERK), based on their critical role in the acquisition and extinction of fear. Pharmacological inactivation of NR2A, but not NR2B, blocked extinction after CR, whereas inactivation of NR2A, NR2B, or both subunits facilitated extinction after PR. The latter finding suggests that co-activation of NR2A and NR2B contributes to persistent fear following PR. In contrast to CR, PR increased membrane levels of ERK and NR2 subunits after the conditioning and extinction sessions, respectively. In parallel, nuclear activation of ERK was significantly reduced after the extinction session. Thus, co-activation and increased surface expression of NR2A and NR2B, possibly mediated by ERK, may cause persistent fear. These findings suggest that patients with post-traumatic stress disorder (PTSD) may benefit from antagonism of specific NR2 subunits.

  16. Diminution of the NMDA receptor NR2B subunit in cortical and subcortical areas of WAG/Rij rats.

    PubMed

    Karimzadeh, Fariba; Soleimani, Mansoureh; Mehdizadeh, Mehdi; Jafarian, Maryam; Mohamadpour, Maliheh; Kazemi, Hadi; Joghataei, Mohammad-Taghi; Gorji, Ali

    2013-12-01

    Modulation of glutamatergic NMDA receptors affects the synchronization of spike discharges in in WAG/Rij rats, a valid genetic animal model of absence epilepsy. In this study, we describe the alteration of NR2B subunit of NMDA receptors expression in WAG/Rij rats in different somatosensory cortical layers and in hippocampal CA1 area. Experimental groups were divided into four groups of six rats of both WAG/Rij and Wistar strains with 2 and 6 months of age. The distribution of NR2B receptors was assessed by immunohistochemical staining in WAG/Rij and compared with age-matched Wistar rats. The expression of NR2B subunit was significantly decreased in different somatosensory cortical layers in 2- and 6-month-old WAG/Rij rats. In addition, the distribution of NR2B in hippocampal CA1 area was lower in 6-month-old WAG/Rij compared with age-matched Wistar rats. The reduction of NR2B receptors in different brain areas points to disturbance of glutamate receptors expression in cortical and subcortical areas in WAG/Rij rats. An altered subunit assembly of NMDA receptors may underlie cortical hyperexcitability in absence epilepsy.

  17. Forebrain NR2B overexpression enhancing fear acquisition and long-term potentiation in the lateral amygdala.

    PubMed

    Duan, Yanhong; Zhou, Siqi; Ma, Jing; Yin, Pengcheng; Cao, Xiaohua

    2015-09-01

    N-methyl-d-aspartic acid (NMDA) receptor-dependent long-term potentiation (LTP) at the thalamus-lateral amygdala (T-LA) synapses is the basis for acquisition of auditory fear memory. However, the role of the NMDA receptor NR2B subunit in synaptic plasticity at T-LA synapses remains speculative. In the present study, using transgenic mice with forebrain-specific overexpression of the NR2B subunit, we have observed that forebrain NR2B overexpression results in enhanced LTP but does not alter long-term depression (LTD) at the T-LA synapses in transgenic mice. To elucidate the cellular mechanisms underlying enhanced LTP at T-LA synapses in these transgenic mice, AMPA and NMDA receptor-mediated postsynaptic currents have been measured. The data show a marked increasing in the amplitude and decay time of NMDA receptor-mediated currents in these transgenic mice. Consistent with enhanced LTP at T-LA synapses, NR2B-transgenic mice exhibit better performance in the acquisition of auditory fear memory than wild-type littermates. Our results demonstrate that up-regulation of NR2B expression facilitates acquisition of auditory cued fear memory and enhances LTP at T-LA synapses.

  18. Effects of diazoxide on Aβ1-42-induced expression of the NR2B subunit in cultured cholinergic neurons.

    PubMed

    Zhu, Jin; Fu, Qingxi; Xia, Chunfeng; Ma, Guozhao

    2015-12-01

    The accumulation of amyloid-β protein (Aβ) is significant in the pathogenesis of Alzheimer's disease. Several previous studies indicate that the NR2B‑containing N‑methyl‑D‑aspartate receptors are critically involved in the Aβ mediated disruption of neuronal function. Diazoxide (DZ), a highly selective drug capable of opening mitochondrial ATP‑sensitive potassium channels, has neuroprotective effects against neuronal cell death. However, the mechanism by which DZ protects cholinergic neurons against Aβ‑induced cytotoxicity remains to be elucidated. The present study was designed to investigate the effects of DZ pretreatment against Aβ1‑42‑induced expression of NR2B in order to gain novel insights into the neuroprotective mechanisms. Following exposure to Aβ1‑42 for 24 h, the expression of the NR2B subunit remained unchanged compared with the control group. However, a significant increase in the expression of the NR2B subunit was observed following treatment with Aβ1‑42 for 72 h (P<0.05); and the upregulation of the expression of the NR2B subunit was reversed by pretreatment with DZ (P<0.05). These results suggested that DZ may counteract Aβ1‑42‑mediated cytotoxicity by alleviating the expression of NR2B.

  19. Silencing the NR2B gene in rat ACC neurons by lentivirus-delivered shRNA alleviates pain-related aversion.

    PubMed

    Guo, Shou-Gang; Lv, Xiu-Hua; Guan, Shan-Hui; Li, Hui-Lu; Qiao, Yong; Feng, Hao; Cong, Lin; Wang, Gong-Ming

    2015-01-01

    The N-methyl-D-aspartate (NMDA) receptor NR2B subunit on neurons in the anterior cingulate cortex (ACC) is implicated in the affective response to noxious stimuli. Selectively silencing this NR2B subunit in ACC neurons could therefore alleviate pain-related aversion. However, to date, there is no optimal approach to selectively silence the NR2B gene in ACC neurons. In the present study, we constructed lentiviral vectors and delivered shRNA (NR2B-RNAi-LV) to effectively silence the NR2B gene in ACC neurons. The use of lentivirus resulted in 95% transfection efficiency and 83% silencing of the NR2B gene in ACC neurons. Electrophysiological experiments showed that the total INMDA was similarly reduced by 48% in lentivirus-transfected ACC neurons. The biochemical and functional data demonstrated that lentiviral shRNA delivery produced a high transfection and silencing efficiency in the ACC neurons. SNI rats weighting 220-250 g were randomly divided into three groups: normal saline group (NS), lenti-siRNA/NC (LV-NC) group, and lenti-siRNA/NR2B (LV-NR2B) group, and conditioned place avoidance was conducted. The results indicated that NR2B-RNAi-LV decreased greatly the conditioning scores of F-CPA while NC-GFP-LV has no effects. NR2B mRNA expression in the NR2B-RNAi-LV group was significantly lower than that in the control group and NC-GFP-LV group. This novel approach of silencing the NR2B gene in ACC neuron could potentially be used to alleviate pain-related aversion.

  20. NR2B-N-Methyl-D-Aspartate Receptors Contribute to Network Asynchrony and Loss of Long-Term Potentiation Following Mild Mechanical Injury In Vitro

    DTIC Science & Technology

    2012-08-30

    REPORT NR2B -N-METHYL-D-ASPARTATE RECEPTORS CONTRIBUTE TO NETWORK ASYNCHRONY AND LOSS OF LONG-TERM POTENTIATION FOLLOWING MILD MECHANICAL INJURY IN...integrate-and-fire model of network activity, 2) simulated an injured network, 3) predicted an important role for the NR2B -NMDA receptor in mediating...ADDRESSES U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS synchrony, NR2B -NMDA receptor, network

  1. NR2B subunit in the prefrontal cortex: A double-edged sword for working memory function and psychiatric disorders

    PubMed Central

    Monaco, Sarah A.; Gulchina, Yelena; Gao, Wen-Jun

    2015-01-01

    The prefrontal cortex (PFC) is a brain region featured with working memory function. The exact mechanism of how working memory operates within the PFC circuitry is unknown, but persistent neuronal firing recorded from prefrontal neurons during a working memory task is proposed to be the neural correlate of this mnemonic encoding. The PFC appears to be specialized for sustaining persistent firing, with N-methyl-D-aspartate (NMDA) receptors, especially slow-decay NR2B subunits, playing an essential role in the maintenance of sustained activity and normal working memory function. However, the NR2B subunit serves as a double-edged sword for PFC function. Because of its slow kinetics, NR2B endows the PFC with not only “neural psychic” properties, but also susceptibilities for neuroexcitotoxicity and psychiatric disorders. This review aims to clarify the interplay among working memory, the PFC, and NMDA receptors; demonstrate the importance of the NR2B subunit in the maintenance of persistent activity; understand the risks and vulnerabilities of how NR2B is related to the development of neuropsychiatric disorders; identify gaps that currently exist in our understanding of these processes; and provide insights regarding future directions that may clarify these issues. We conclude that the PFC is a specialized brain region with distinct delayed maturation, unique neuronal circuitry, and characteristic NMDA receptor function. The unique properties and development of NMDA receptors, especially enrichment of NR2B subunits, endows the PFC with not only the capability to generate sustained activity for working memory, but also serves as a major vulnerability to environmental insults and risk factors for psychiatric disorders. PMID:26143512

  2. NR2B subunit in the prefrontal cortex: A double-edged sword for working memory function and psychiatric disorders.

    PubMed

    Monaco, Sarah A; Gulchina, Yelena; Gao, Wen-Jun

    2015-09-01

    The prefrontal cortex (PFC) is a brain region featured with working memory function. The exact mechanism of how working memory operates within the PFC circuitry is unknown, but persistent neuronal firing recorded from prefrontal neurons during a working memory task is proposed to be the neural correlate of this mnemonic encoding. The PFC appears to be specialized for sustaining persistent firing, with N-methyl-D-aspartate (NMDA) receptors, especially slow-decay NR2B subunits, playing an essential role in the maintenance of sustained activity and normal working memory function. However, the NR2B subunit serves as a double-edged sword for PFC function. Because of its slow kinetics, NR2B endows the PFC with not only "neural psychic" properties, but also susceptibilities for neuroexcitotoxicity and psychiatric disorders. This review aims to clarify the interplay among working memory, the PFC, and NMDA receptors; demonstrate the importance of NR2B in the maintenance of persistent activity; understand the risks and vulnerabilities of how NR2B is related to the development of neuropsychiatric disorders; identify gaps that currently exist in our understanding of these processes; and provide insights regarding future directions that may clarify these issues. We conclude that the PFC is a specialized brain region with distinct delayed maturation, unique neuronal circuitry, and characteristic NMDA receptor function. The unique properties and development of NMDA receptors, especially enrichment of NR2B subunits, endow the PFC with not only the capability to generate sustained activity for working memory, but also serves as a major vulnerability to environmental insults and risk factors for psychiatric disorders.

  3. Alpha-synuclein modulates NR2B-containing NMDA receptors and decreases their levels after rotenone exposure.

    PubMed

    Navarria, Laura; Zaltieri, Michela; Longhena, Francesca; Spillantini, Maria Grazia; Missale, Cristina; Spano, PierFranco; Bellucci, Arianna

    2015-01-01

    Alpha-synuclein (α-syn) is the main protein component of Lewy bodies (LBs), that together with nigrostriatal dopamine neuron loss constitute typical pathological hallmarks of Parkinson's disease (PD). Glutamate N-methyl-d-aspartate receptor (NMDAR) abnormalities, peculiarly involving NR2B-containing NMDAR, have been observed in the brain of PD patients and in several experimental models of the disease. Recent findings, indicating that α-syn can modulate NMDAR trafficking and function, suggest that this protein may be a pivotal regulator of NMDAR activity. Prompted by these evidences, we used fluorescence immunocytochemistry, western blotting and ratiometric Ca(2+) measurements to investigate whether wild type (wt) or C-terminally truncated α-syn can specifically modulate NR2B-containing NMDAR levels, subcellular trafficking and function. In addition, we evaluated whether the exposure of primary cortical neurons to increasing concentrations of rotenone could differentially regulate NR2B levels and cell viability in the presence or in the absence of α-syn. Our results indicate that both wt and C-terminally truncated α-syn negatively modulate NR2B-containing NMDAR levels, membrane translocation and function. Moreover, we found that absence of α-syn abolishes the rotenone-dependent decrease of NR2B levels and reduces neuronal vulnerability in primary cortical neurons. These findings suggest that α-syn can modulate neuronal resilience by regulating NR2B-containing NMDAR, whose specific alterations could connect α-syn pathology to neuronal degeneration in PD.

  4. Delay-dependent impairment of spatial working memory with inhibition of NR2B-containing NMDA receptors in hippocampal CA1 region of rats.

    PubMed

    Zhang, Xue-Han; Liu, Shu-Su; Yi, Feng; Zhuo, Min; Li, Bao-Ming

    2013-03-13

    Hippocampal N-methyl-D-aspartate receptor (NMDAR) is required for spatial working memory. Although evidence from genetic manipulation mice suggests an important role of hippocampal NMDAR NR2B subunits (NR2B-NMDARs) in spatial working memory, it remains unclear whether or not the requirement of hippocampal NR2B-NMDARs for spatial working memory depends on the time of spatial information maintained. Here, we investigate the contribution of hippocampal NR2B-NMDARs to spatial working memory on delayed alternation task in T-maze (DAT task) and delayed matched-to-place task in water maze (DMP task). Our data show that infusions of the NR2B-NMDAR selective antagonists, Ro25-6981 or ifenprodil, directly into the CA1 region, impair spatial working memory in DAT task with 30-s delay (not 5-s delay), but severely impair error-correction capability in both 5-s and 30-s delay task. Furthermore, intra-CA1 inhibition of NR2B-NMDARs impairs spatial working memory in DMP task with 10-min delay (not 30-s delay). Our results suggest that hippocampal NR2B-NMDARs are required for spatial working memory in long-delay task, whereas spare for spatial working memory in short-delay task. We conclude that the requirement of NR2B-NMDARs for spatial working memory is delay-dependent in the CA1 region.

  5. NR2B Expression in Rat DRG Is Differentially Regulated Following Peripheral Nerve Injuries That Lead to Transient or Sustained Stimuli-Evoked Hypersensitivity

    PubMed Central

    Norcini, Monica; Sideris, Alexandra; Adler, Samantha M.; Hernandez, Lourdes A. M.; Zhang, Jin; Blanck, Thomas J. J.; Recio-Pinto, Esperanza

    2016-01-01

    Following injury, primary sensory neurons undergo changes that drive central sensitization and contribute to the maintenance of persistent hypersensitivity. NR2B expression in the dorsal root ganglia (DRG) has not been previously examined in neuropathic pain models. Here, we investigated if changes in NR2B expression within the DRG are associated with hypersensitivities that result from peripheral nerve injuries. This was done by comparing the NR2B expression in the DRG derived from two modalities of the spared nerve injury (SNI) model, since each variant produces different neuropathic pain phenotypes. Using the electronic von Frey to stimulate the spared and non-spared regions of the hindpaws, we demonstrated that sural-SNI animals develop sustained neuropathic pain in both regions while the tibial-SNI animals recover. NR2B expression was measured at Day 23 and Day 86 post-injury. At Day 23 and 86 post-injury, sural-SNI animals display strong hypersensitivity, whereas tibial-SNI animals display 50 and 100% recovery from post-injury-induced hypersensitivity, respectively. In tibial-SNI at Day 86, but not at Day 23 the perinuclear region of the neuronal somata displayed an increase in NR2B protein. This retention of NR2B protein within the perinuclear region, which will render them non-functional, correlates with the recovery observed in tibial-SNI. In sural-SNI at Day 86, DRG displayed an increase in NR2B mRNA which correlates with the development of sustained hypersensitivity in this model. The increase in NR2B mRNA was not associated with an increase in NR2B protein within the neuronal somata. The latter may result from a decrease in kinesin Kif17, since Kif17 mediates NR2B transport to the soma’s plasma membrane. In both SNIs, microglia/macrophages showed a transient increase in NR2B protein detected at Day 23 but not at Day 86, which correlates with the initial post-injury induced hypersensitivity in both SNIs. In tibial-SNI at Day 86, but not at Day 23

  6. NR2B Expression in Rat DRG Is Differentially Regulated Following Peripheral Nerve Injuries That Lead to Transient or Sustained Stimuli-Evoked Hypersensitivity.

    PubMed

    Norcini, Monica; Sideris, Alexandra; Adler, Samantha M; Hernandez, Lourdes A M; Zhang, Jin; Blanck, Thomas J J; Recio-Pinto, Esperanza

    2016-01-01

    Following injury, primary sensory neurons undergo changes that drive central sensitization and contribute to the maintenance of persistent hypersensitivity. NR2B expression in the dorsal root ganglia (DRG) has not been previously examined in neuropathic pain models. Here, we investigated if changes in NR2B expression within the DRG are associated with hypersensitivities that result from peripheral nerve injuries. This was done by comparing the NR2B expression in the DRG derived from two modalities of the spared nerve injury (SNI) model, since each variant produces different neuropathic pain phenotypes. Using the electronic von Frey to stimulate the spared and non-spared regions of the hindpaws, we demonstrated that sural-SNI animals develop sustained neuropathic pain in both regions while the tibial-SNI animals recover. NR2B expression was measured at Day 23 and Day 86 post-injury. At Day 23 and 86 post-injury, sural-SNI animals display strong hypersensitivity, whereas tibial-SNI animals display 50 and 100% recovery from post-injury-induced hypersensitivity, respectively. In tibial-SNI at Day 86, but not at Day 23 the perinuclear region of the neuronal somata displayed an increase in NR2B protein. This retention of NR2B protein within the perinuclear region, which will render them non-functional, correlates with the recovery observed in tibial-SNI. In sural-SNI at Day 86, DRG displayed an increase in NR2B mRNA which correlates with the development of sustained hypersensitivity in this model. The increase in NR2B mRNA was not associated with an increase in NR2B protein within the neuronal somata. The latter may result from a decrease in kinesin Kif17, since Kif17 mediates NR2B transport to the soma's plasma membrane. In both SNIs, microglia/macrophages showed a transient increase in NR2B protein detected at Day 23 but not at Day 86, which correlates with the initial post-injury induced hypersensitivity in both SNIs. In tibial-SNI at Day 86, but not at Day 23

  7. Activation of 5-HT and NR2B contributes to visceral hypersensitivity in irritable bowel syndrome in rats

    PubMed Central

    Chen, Ming-Xian; Chen, Yu; Fu, Rui; Liu, Sai-Yue; Yang, Qin-Qin; Shen, Tang-Biao

    2016-01-01

    The roles of 5-hydroxytryptamine (5-HT) and spinal N-methyl-D-aspartic acid receptor 2B (NR2B) in visceral hypersensitivity were investigated. A rat model with irritable bowel syndrome (IBS) was established by intracolonic injections of acetic acid onpost-natal days 8-21. Rats were randomly divided into five groups: normal intact (control) group, IBS model group, Ro25-6981-treated IBS rats (Ro25-6981, a NR2B antagonist) group, amitriptyline-treated IBS rats (amitriptyline, a 5-HT antagonist) and Ro25-6981 plus amitriptyline-treated IBS rats (Ro25-6981+amitriptyline) group. The expressions of 5-HT, NR2B, 5-HT2AR, 5-HT7R, SERT, TNF-α and IL-1β in colon, dorsal root ganglion (DRG) and hypothalamus, respectively, were measured by Immunohistochemical staining, Real-Time Reverse Transcription-PCR and Western blotting. Our results showed increased DRG and hypothalamus expression of 5-HT, NR2B, 5-HT2AR, 5-HT7R in IBS model group and decreased expression of those in Ro25-6981 and amitriptyline alone or both treatment groups. Moreover, SERT expression was decreased in colorectal, DRG and hypothalamus of ISB model rats, but increased by Ro25-6981 and amitriptyline alone or both treatments. Ro25-6981 and amitriptyline treatment also decreased colorectal expression of TNF-α and IL-1β induced by IBS model. In conclusion, activation of 5-HT and NR2B may play a crucial role in visceral hypersensitivity in irritable bowel syndrome in rats. PMID:28078028

  8. Activation of 5-HT and NR2B contributes to visceral hypersensitivity in irritable bowel syndrome in rats.

    PubMed

    Chen, Ming-Xian; Chen, Yu; Fu, Rui; Liu, Sai-Yue; Yang, Qin-Qin; Shen, Tang-Biao

    2016-01-01

    The roles of 5-hydroxytryptamine (5-HT) and spinal N-methyl-D-aspartic acid receptor 2B (NR2B) in visceral hypersensitivity were investigated. A rat model with irritable bowel syndrome (IBS) was established by intracolonic injections of acetic acid onpost-natal days 8-21. Rats were randomly divided into five groups: normal intact (control) group, IBS model group, Ro25-6981-treated IBS rats (Ro25-6981, a NR2B antagonist) group, amitriptyline-treated IBS rats (amitriptyline, a 5-HT antagonist) and Ro25-6981 plus amitriptyline-treated IBS rats (Ro25-6981+amitriptyline) group. The expressions of 5-HT, NR2B, 5-HT2AR, 5-HT7R, SERT, TNF-α and IL-1β in colon, dorsal root ganglion (DRG) and hypothalamus, respectively, were measured by Immunohistochemical staining, Real-Time Reverse Transcription-PCR and Western blotting. Our results showed increased DRG and hypothalamus expression of 5-HT, NR2B, 5-HT2AR, 5-HT7R in IBS model group and decreased expression of those in Ro25-6981 and amitriptyline alone or both treatment groups. Moreover, SERT expression was decreased in colorectal, DRG and hypothalamus of ISB model rats, but increased by Ro25-6981 and amitriptyline alone or both treatments. Ro25-6981 and amitriptyline treatment also decreased colorectal expression of TNF-α and IL-1β induced by IBS model. In conclusion, activation of 5-HT and NR2B may play a crucial role in visceral hypersensitivity in irritable bowel syndrome in rats.

  9. Mas-Related Gene (Mrg) C Activation Attenuates Bone Cancer Pain via Modulating Gi and NR2B

    PubMed Central

    Lu, Cui’e; Lei, Yishan; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    Objective This study is to investigate the role of Mas-related gene (Mrg) C in the pathogenesis and treatment of bone cancer pain (BCP). Methods BCP mouse model was established by osteosarcoma cell inoculation. Pain-related behaviors were assessed with the spontaneous lifting behavior test and mechanical allodynia test. Expression levels of MrgC, Gi, and NR2B in the spinal cord were detected with Western blot analysis and immunohistochemistry. Results Pain-related behavior tests showed significantly increased spontaneous flinches (NSF) and decreased paw withdrawal mechanical threshold (PWMT) in mouse models of BCP. Western blot analysis showed that, compared with the control group and before modeling, all the expression levels of MrgC, Gi, and NR2B in the spinal cord of BCP mice were dramatically elevated, which were especially increased at day 7 after operation and thereafter, in a time-dependent manner. Moreover, the treatment of MrgC agonist BAM8-22 significantly up-regulated Gi and down-regulated NR2B expression levels, in the spinal cord of BCP mice, in a time-dependent manner. On the other hand, anti-MrgC significantly down-regulated Gi expression, while dramatically up-regulated NR2B expression, in the BCP mice. Similar results were obtained from the immunohistochemical detection. Importantly, BAM8-22 significantly attenuated the nociceptive behaviors in the BCP mice. Conclusion Our results indicated the MrgC-mediated Gi and NR2B expression alterations in the BCP mice, which might contribute to the pain hypersensitivity. These findings may provide a novel strategy for the treatment of BCP in clinic. PMID:27152740

  10. PSD95 suppresses dendritic arbor development in mature hippocampal neurons by occluding the clustering of NR2B-NMDA receptors.

    PubMed

    Bustos, Fernando J; Varela-Nallar, Lorena; Campos, Matias; Henriquez, Berta; Phillips, Marnie; Opazo, Carlos; Aguayo, Luis G; Montecino, Martin; Constantine-Paton, Martha; Inestrosa, Nibaldo C; van Zundert, Brigitte

    2014-01-01

    Considerable evidence indicates that the NMDA receptor (NMDAR) subunits NR2A and NR2B are critical mediators of synaptic plasticity and dendritogenesis; however, how they differentially regulate these processes is unclear. Here we investigate the roles of the NR2A and NR2B subunits, and of their scaffolding proteins PSD-95 and SAP102, in remodeling the dendritic architecture of developing hippocampal neurons (2-25 DIV). Analysis of the dendritic architecture and the temporal and spatial expression patterns of the NMDARs and anchoring proteins in immature cultures revealed a strong positive correlation between synaptic expression of the NR2B subunit and dendritogenesis. With maturation, the pruning of dendritic branches was paralleled by a strong reduction in overall and synaptic expression of NR2B, and a significant elevation in synaptic expression of NR2A and PSD95. Using constructs that alter the synaptic composition, we found that either over-expression of NR2B or knock-down of PSD95 by shRNA-PSD95 augmented dendritogenesis in immature neurons. Reactivation of dendritogenesis could also be achieved in mature cultured neurons, but required both manipulations simultaneously, and was accompanied by increased dendritic clustering of NR2B. Our results indicate that the developmental increase in synaptic expression of PSD95 obstructs the synaptic clustering of NR2B-NMDARs, and thereby restricts reactivation of dendritic branching. Experiments with shRNA-PSD95 and chimeric NR2A/NR2B constructs further revealed that C-terminus of the NR2B subunit (tail) was sufficient to induce robust dendritic branching in mature hippocampal neurons, and suggest that the NR2B tail is important in recruiting calcium-dependent signaling proteins and scaffolding proteins necessary for dendritogenesis.

  11. Positive feedback of NR2B-containing NMDA receptor activity is the initial step toward visual imprinting: a model for juvenile learning.

    PubMed

    Nakamori, Tomoharu; Sato, Katsushige; Kinoshita, Masae; Kanamatsu, Tomoyuki; Sakagami, Hiroyuki; Tanaka, Kohichi; Ohki-Hamazaki, Hiroko

    2015-01-01

    Imprinting in chicks is a good model for elucidating the processes underlying neural plasticity changes during juvenile learning. We recently reported that neural activation of a telencephalic region, the core region of the hyperpallium densocellulare (HDCo), was critical for success of visual imprinting, and that N-Methyl-D-aspartic (NMDA) receptors containing the NR2B subunit (NR2B/NR1) in this region were essential for imprinting. Using electrophysiological and multiple-site optical imaging techniques with acute brain slices, we found that long-term potentiation (LTP) and enhancement of NR2B/NR1 currents in HDCo neurons were induced in imprinted chicks. Enhancement of NR2B/NR1 currents as well as an increase in surface NR2B expression occurred even following a brief training that was too weak to induce LTP or imprinting behavior. This means that NR2B/NR1 activation is the initial step of learning, well before the activation of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptors which induces LTP. We also showed that knockdown of NR2B/NR1 inhibited imprinting, and inversely, increasing the surface NR2B expression by treatment with a casein kinase 2 inhibitor successfully reduced training time required for imprinting. These results suggest that imprinting stimuli activate post-synaptic NR2B/NR1 in HDCo cells, increase NR2B/NR1 signaling through up-regulation of its expression, and induce LTP and memory acquisition. The study investigated the neural mechanism underlying juvenile learning. In the initial stage of chick imprinting, NMDA receptors containing the NMDA receptor subunit 2B (NR2B) are activated, surface expression of NR2B/NR1 (NMDA receptor subunit 1) is up-regulated, and consequently long-term potentiation is induced in the telencephalic neurons. We suggest that the positive feedback in the NR2B/NR1 activation is a unique process of juvenile learning, exhibiting rapid memory acquisition.

  12. Spinal serum-inducible and glucocorticoid-inducible kinase 1 mediates neuropathic pain via kalirin and downstream PSD-95-dependent NR2B phosphorylation in rats.

    PubMed

    Peng, Hsien-Yu; Chen, Gin-Den; Lai, Cheng-Yuan; Hsieh, Ming-Chun; Lin, Tzer-Bin

    2013-03-20

    The coupling of the spinal postsynaptic density-95 (PSD-95) with the glutamatergic N-methyl-d-aspartate receptor NR2B subunit and the subsequent NR2B phosphorylation contribute to pain-related plasticity. Increasing evidence reveals that kalirin, a Rho-guanine nucleotide exchange factor, modulates PSD-95-NR2B-dependent neuroplasticity. Our laboratory recently demonstrated that serum-inducible and glucocorticoid-inducible kinase 1 (SGK1) participates in inflammation-associated pain hypersensitivity by modulating spinal glutamatergic neurotransmission. Because kalirin is one of the proteins in PSD that is highly phosphorylated by various kinases, we tested whether kalirin could be a downstream target of spinal SGK1 that participates in neuropathic pain development via regulation of the PSD-95-NR2B coupling-dependent phosphorylation of NR2B. We observed that spinal nerve ligation (SNL, L5) in male Sprague Dawley rats resulted in behavioral allodynia, which was associated with phosphorylated SGK1 (pSGK1), kalirin, and phosphorylated NR2B (pNR2B) expression and an increase in pSGK1-kalirin-PSD-95-pNR2B coprecipitation in the ipsilateral dorsal horn (L4-L5). SNL-enhanced kalirin immunofluorescence was coincident with pSGK1, PSD-95, and pNR2B immunoreactivity. Small-interfering RNA (siRNA) that targeted spinal kalirin mRNA expression (10 μg, 10 μl; i.t.) reduced SNL-induced allodynia, kalirin and pNR2B expression, as well as kalirin-PSD-95 and PSD-95-pNR2B coupling and costaining without affecting SGK1 phosphorylation. Daily administration of GSK-650394 (an SGK1 antagonist; 100 nm, 10 μl, i.t.) not only exhibited effects similar to the kalirin mRNA-targeting siRNA but also attenuated pSGK1-kalirin costaining and SGK1-kalirin coupling. We suggest that nerve injury could induce spinal SGK1 phosphorylation that subsequently interacts with and upregulates kalirin to participate in neuropathic pain development via PSD-95-NR2B coupling-dependent NR2B phosphorylation.

  13. Regulation of PINK1 by NR2B-containing NMDA receptors in ischemic neuronal injury.

    PubMed

    Shan, Yuexin; Liu, Baosong; Li, Lijun; Chang, Ning; Li, Lei; Wang, Hanbin; Wang, Dianshi; Feng, Hua; Cheung, Carol; Liao, Mingxia; Cui, Tianyuan; Sugita, Shuzo; Wan, Qi

    2009-12-01

    Dysfunction of PTEN-induced kinase-1 (PINK1) is implicated in neurodegeneration. We report here that oxygen-glucose deprivation (OGD), an in vitro insult mimicking ischemic neuron injury, resulted in a significant reduction of PINK1 protein expression in cultured cortical neurons. The decrease of PINK1 expression was blocked by the antagonists of NMDA receptors. We revealed that the overactivation of NR2B-containing NMDA receptors (NR2BRs) was responsible for the OGD-induced PINK1 reduction. The overactivated NR2BRs also inhibited the phosphorylation, but not the protein expression, of the cell survival-promoting kinase Akt after OGD insult, indicating that OGD-induced reduction of PINK1 protein is specific in the injury paradigm. We further showed that enhancing the protein expression of PINK1 antagonized OGD-induced reduction of Akt phosphorylation, suggesting that Akt may be a downstream target of PINK1 in ischemic neuron injury. Importantly, we provided evidence that both NR2BR antagonist and PINK1 over-expression protected against OGD-induced neuronal death. These results suggest that the overactivation of NR2BRs may contribute to ischemic neuron death through suppressing PINK1-dependent survival signaling. Thus, selectively antagonizing NR2BR signal pathway-induced neurotoxicity may be a potential neuroprotection strategy.

  14. Tyrosine phosphorylation of the NR2B subunit of the NMDA receptor in the spinal cord contributes to chronic visceral pain in rats.

    PubMed

    Luo, Xiao-Qing; Cai, Qin-Yan; Chen, Yu; Guo, Li-Xia; Chen, Ai-Qin; Wu, Zhen-Quan; Lin, Chun

    2014-01-13

    The roles of spinal N-methyl-d-aspartic acid receptor 2B (NR2B) subunit in central sensitization of chronic visceral pain were investigated. A rat model with irritable bowel syndrome (IBS) was established by colorectal distention (CRD) on post-natal days 8-14. Responses of the external oblique muscle of the abdomen to CRD were measured to evaluate the sensitivity of visceral pain in rats. The sensitivity of visceral pain significantly increased in IBS-like rats. Expressions of spinal NR2B subunit and phosphorylated NR2B subunit significantly increased by 50-55% in IBS-like rats when compared with those in control rats. Ro 25-6981, a selective antagonist of NR2B subunit, has a dose-dependent anti-allodynic and anti-hyperalgesic effect without causing motor dysfunction in IBS-like rats. Furthermore, the activation mechanism of the spinal NR2B subunit in chronic visceral pain was also investigated. Spinal administration of genistein, a specific inhibitor of tyrosine kinases, also decreased the visceral pain hypersensitivity of IBS-like rats in a dose-dependent manner. In addition, the expression of phosphorylated NR2B subunit was decreased after spinal administration of Ro 25-6981 or genistein in IBS-like rats. In conclusion, tyrosine kinase activation-induced phosphorylation of NR2B subunit may play a crucial role in central sensitization of chronic visceral pain.

  15. Effects of L-DOPA and STN-HFS dyskinesiogenic treatments on NR2B regulation in basal ganglia in the rat model of Parkinson's disease.

    PubMed

    Quintana, Adrien; Sgambato-Faure, Véronique; Savasta, Marc

    2012-12-01

    Dyskinesia is a major side effect of chronic levodopa (L-DOPA) administration, the reference treatment for Parkinson's disease (PD). High-frequency stimulation of the subthalamic nucleus (STN-HFS) alleviates parkinsonian motor symptoms and indirectly improves dyskinesia by decreasing L-DOPA requirement. However, inadequate stimulation can also trigger dyskinetic movements in PD patients and animal models. Here, we investigated the possible association between L-DOPA- and STN-HFS-induced dyskinesia and regulation of the NR2B subunit of NMDA receptors in the rodent model of PD. We subjected 6-OHDA-lesioned rats to HFS for 1h, at an intensity triggering forelimb dyskinesia. Other 6-OHDA-lesioned rats were treated with chronic high doses of L-DOPA for ten days, to induce abnormal involuntary movements. The 6-OHDA lesion regulated NR2B only in the SNr, where the activation of NR2B was observed (as assessed by phosphorylation of the Tyr1472 residue). Both STN-HFS and L-DOPA dyskinesiogenic treatments induced NR2B activation in the STN and EP, but only L-DOPA triggered NR2B hyperphosphorylation in the striatum. Finally, the use of CP-101,606 exacerbated L-DOPA-induced motor behavior and associated NR2B hyperphosphorylation in the striatum, STN and EP. Thus, NR2B activation in basal ganglia structures is correlated with dyskinesia.

  16. NR2B-dependent Cyclophilin D translocation suppresses the recovery of synaptic transmission after oxygen-glucose deprivation

    PubMed Central

    Yan, Shijun; Du, Fang; Yan, Shirley Shidu

    2016-01-01

    N-methyl D-aspartate receptor (NMDA) subunit 2B (NR2B)-containing NMDA receptors and mitochondrial protein cyclophilin D (CypD) are well characterized in mediating neuronal death after ischemia, respectively. However, whether and how NR2B and CypD work together in mediating synaptic injury after ischemia remains elusive. Using a de novo ischemia model of oxygen-glucose deprivation (OGD) in hippocampal slices, we identified a NR2B-dependent mechanism for CypD translocation onto the mitochondrial inner membrane. CypD depletion (CypD null mice) prevented OGD-induced impairment in synaptic transmission recovery. Overexpression of neuronal CypD mice (CypD+) exacerbated OGD-induced loss of synaptic transmission. Inhibition of CypD-dependent mitochondrial permeability transition pore (mPTP) opening by cyclosporine A (CSA) attenuated ischemia-induced synaptic perturbation in CypD+ and non-transgenic (nonTg) mice. The treatment of antioxidant EUK134 to suppress mitochondrial oxidative stress rescued CypD-mediated synaptic dysfunction following OGD in CypD+ slices. Furthermore, OGD provoked the interaction of CypD with P53, which was enhanced in slices overexpressing CypD but was diminished in CypD-null slices Inhibition of p53 using a specific inhibitor of p53 (pifithrin-μ) attenuated the CypD/p53 interaction following OGD, along with a restored synaptic transmission in both nonTg and CypD+ hippocampal slices. Our results indicate that OGD-induced CypD translocation potentiates CypD/P53 interaction in a NR2B dependent manner, promoting oxidative stress and loss of synaptic transmission. We also evaluate a new ex-vivo chronic OGD-induced ischemia model for studying the effect of oxidative stress on synaptic damage. PMID:26232180

  17. NR2B-dependent cyclophilin D translocation suppresses the recovery of synaptic transmission after oxygen-glucose deprivation.

    PubMed

    Zhang, Zhihua; Wang, Yongfu; Yan, Shijun; Du, Fang; Yan, Shirley Shidu

    2015-10-01

    N-methyl d-aspartate receptor (NMDA) subunit 2B (NR2B)-containing NMDA receptors and mitochondrial protein cyclophilin D (CypD) are well characterized in mediating neuronal death after ischemia, respectively. However, whether and how NR2B and CypD work together in mediating synaptic injury after ischemia remains elusive. Using an ex vivo ischemia model of oxygen-glucose deprivation (OGD) in hippocampal slices, we identified a NR2B-dependent mechanism for CypD translocation onto the mitochondrial inner membrane. CypD depletion (CypD null mice) prevented OGD-induced impairment in synaptic transmission recovery. Overexpression of neuronal CypD mice (CypD+) exacerbated OGD-induced loss of synaptic transmission. Inhibition of CypD-dependent mitochondrial permeability transition pore (mPTP) opening by cyclosporine A (CSA) attenuated ischemia-induced synaptic perturbation in CypD+ and non-transgenic (non-Tg) mice. The treatment of antioxidant EUK134 to suppress mitochondrial oxidative stress rescued CypD-mediated synaptic dysfunction following OGD in CypD+ slices. Furthermore, OGD provoked the interaction of CypD with P53, which was enhanced in slices overexpressing CypD but was diminished in CypD-null slices. Inhibition of p53 using a specific inhibitor of p53 (pifithrin-μ) attenuated the CypD/p53 interaction following OGD, along with a restored synaptic transmission in both non-Tg and CypD+ hippocampal slices. Our results indicate that OGD-induced CypD translocation potentiates CypD/P53 interaction in a NR2B dependent manner, promoting oxidative stress and loss of synaptic transmission. We also evaluate a new ex vivo chronic OGD-induced ischemia model for studying the effect of oxidative stress on synaptic damage.

  18. NR2B Antagonist CP-101,606 Abolishes Pitch-Mediated Deviance Detection in Awake Rats.

    PubMed

    Sivarao, Digavalli V; Chen, Ping; Yang, Yili; Li, Yu-Wen; Pieschl, Rick; Ahlijanian, Michael K

    2014-01-01

    Schizophrenia patients exhibit a decreased ability to detect change in their auditory environment as measured by auditory event-related potentials (ERP) such as mismatch negativity. This deficit has been linked to abnormal NMDA neurotransmission since, among other observations, non-selective channel blockers of NMDA reliably diminish automatic deviance detection in human subjects as well as in animal models. Recent molecular and functional evidence links NR2B receptor subtype to aberrant NMDA transmission in schizophrenia. However, it is unknown if NR2B receptors participate in pre-attentive deviance detection. We recorded ERP from the vertex of freely behaving rats in response to frequency mismatch protocols. We saw a robust increase in N1 response to deviants compared to standard as well as control stimuli indicating true deviance detection. Moreover, the increased negativity was highly sensitive to deviant probability. Next, we tested the effect of a non-selective NMDA channel blocker (ketamine, 30 mg/kg) and a highly selective NR2B antagonist, CP-101,606 (10 or 30 mg/kg) on deviance detection. Ketamine attenuated deviance mainly by increasing the amplitude of the standard ERP. Amplitude and/or latency of several ERP components were also markedly affected. In contrast, CP-101,606 robustly and dose-dependently inhibited the deviant's N1 amplitude, and as a consequence, completely abolished deviance detection. No other ERPs or components were affected. Thus, we report first evidence that NR2B receptors robustly participate in processes of automatic deviance detection in a rodent model. Lastly, our model demonstrates a path forward to test specific pharmacological hypotheses using translational endpoints relevant to aberrant sensory processing in schizophrenia.

  19. NR2B-NMDA receptor mediated modulation of the tyrosine phosphatase STEP regulates glutamate induced neuronal cell death

    PubMed Central

    Poddar, Ranjana; Deb, Ishani; Mukherjee, Saibal; Paul, Surojit

    2011-01-01

    The present study examines the role of a neuron-specific tyrosine phosphatase (STEP) in excitotoxic cell death. Our findings demonstrate that p38 MAPK, a stress-activated kinase that is known to play a role in the etiology of excitotoxic cell death is a substrate of STEP. Glutamate-mediated NMDA receptor stimulation leads to rapid but transient activation of p38 MAPK, which is primarily dependent on NR2A-NMDA receptor activation. Conversely, activation of NR2B-NMDA receptors leads to dephosphorylation and subsequent activation of STEP, which in turn leads to inactivation of p38 MAPK. Thus during transient NMDA receptor stimulation, increases in STEP activity appears to limit the duration of activation of p38 MAPK and improves neuronal survival. However, if NR2B-NMDA receptor stimulation is sustained, protective effects of STEP activation are lost, as these stimuli cause significant degradation of active STEP, leading to secondary activation of p38 MAP kinase. Consistent with this observation, a cell transducible TAT-STEP peptide that constitutively binds to p38 MAPK attenuated neuronal cell death caused by sustained NMDA receptor stimulation. The findings imply that the activation and levels of STEP are dependent on the duration and magnitude of NR2B-NMDA receptor stimulation and STEP serves as a modulator of NMDA receptor dependent neuronal injury, through its regulation of p38 MAPK. PMID:21029094

  20. Protons trap NR1/NR2B NMDA receptors in a nonconducting state.

    PubMed

    Banke, Tue G; Dravid, Shashank M; Traynelis, Stephen F

    2005-01-05

    NMDA receptors are highly expressed in the CNS and are involved in excitatory synaptic transmission, as well as synaptic plasticity. Given that overstimulation of NMDA receptors can cause cell death, it is not surprising that these channels are under tight control by a series of inhibitory extracellular ions, including zinc, magnesium, and H+. We studied the inhibition by extracellular protons of recombinant NMDA receptor NR1/NR2B single-channel and macroscopic responses in transiently transfected human embryonic kidney HEK 293 cells using patch-clamp techniques. We report that proton inhibition proceeds identically in the absence or presence of agonist, which rules out the possibility that protonation inhibits receptors by altering coagonist binding. The response of macroscopic currents in excised patches to rapid jumps in pH was used to estimate the microscopic association and dissociation rates for protons, which were 1.4 x 10(9) m(-1) sec(-1) and 110-196 sec(-1), respectively (K(d) corresponds to pH 7.2). Protons reduce the open probability without altering the time course of desensitization or deactivation. Protons appear to slow at least one time constant describing the intra-activation shut-time histogram and modestly reduce channel open time, which we interpret to reflect a reduction in the overall channel activation rate and possible proton-induced termination of openings. This is consistent with a modest proton-dependent slowing of the macroscopic response rise time. From these data, we propose a physical model of proton inhibition that can describe macroscopic and single-channel properties of NMDA receptor function over a range of pH values.

  1. The qEEG Signature of Selective NMDA NR2B Negative Allosteric Modulators; A Potential Translational Biomarker for Drug Development.

    PubMed

    Keavy, Deborah; Bristow, Linda J; Sivarao, Digavalli V; Batchelder, Margaret; King, Dalton; Thangathirupathy, Srinivasan; Macor, John E; Weed, Michael R

    2016-01-01

    The antidepressant activity of the N-methyl-D-aspartate (NMDA) receptor channel blocker, ketamine, has led to the investigation of negative allosteric modulators (NAMs) selective for the NR2B receptor subtype. The clinical development of NR2B NAMs would benefit from a translational pharmacodynamic biomarker that demonstrates brain penetration and functional inhibition of NR2B receptors in preclinical species and humans. Quantitative electroencephalography (qEEG) is a translational measure that can be used to demonstrate pharmacodynamic effects across species. NMDA receptor channel blockers, such as ketamine and phencyclidine, increase the EEG gamma power band, which has been used as a pharmacodynamic biomarker in the development of NMDA receptor antagonists. However, detailed qEEG studies with ketamine or NR2B NAMs are lacking in nonhuman primates. The aim of the present study was to determine the effects on the qEEG power spectra of the NR2B NAMs traxoprodil (CP-101,606) and BMT-108908 in nonhuman primates, and to compare them to the NMDA receptor channel blockers, ketamine and lanicemine. Cynomolgus monkeys were surgically implanted with EEG radio-telemetry transmitters, and qEEG was measured after vehicle or drug administration. The relative power for a number of frequency bands was determined. Ketamine and lanicemine increased relative gamma power, whereas the NR2B NAMs traxoprodil and BMT-108908 had no effect. Robust decreases in beta power were elicited by ketamine, traxoprodil and BMT-108908; and these agents also produced decreases in alpha power and increases in delta power at the doses tested. These results suggest that measurement of power spectra in the beta and delta bands may represent a translational pharmacodynamic biomarker to demonstrate functional effects of NR2B NAMs. The results of these studies may help guide the selection of qEEG measures that can be incorporated into early clinical evaluation of NR2B NAMs in healthy humans.

  2. The qEEG Signature of Selective NMDA NR2B Negative Allosteric Modulators; A Potential Translational Biomarker for Drug Development

    PubMed Central

    Keavy, Deborah; Bristow, Linda J.; Sivarao, Digavalli V.; Batchelder, Margaret; King, Dalton; Thangathirupathy, Srinivasan; Macor, John E.; Weed, Michael R.

    2016-01-01

    The antidepressant activity of the N-methyl-D-aspartate (NMDA) receptor channel blocker, ketamine, has led to the investigation of negative allosteric modulators (NAMs) selective for the NR2B receptor subtype. The clinical development of NR2B NAMs would benefit from a translational pharmacodynamic biomarker that demonstrates brain penetration and functional inhibition of NR2B receptors in preclinical species and humans. Quantitative electroencephalography (qEEG) is a translational measure that can be used to demonstrate pharmacodynamic effects across species. NMDA receptor channel blockers, such as ketamine and phencyclidine, increase the EEG gamma power band, which has been used as a pharmacodynamic biomarker in the development of NMDA receptor antagonists. However, detailed qEEG studies with ketamine or NR2B NAMs are lacking in nonhuman primates. The aim of the present study was to determine the effects on the qEEG power spectra of the NR2B NAMs traxoprodil (CP-101,606) and BMT-108908 in nonhuman primates, and to compare them to the NMDA receptor channel blockers, ketamine and lanicemine. Cynomolgus monkeys were surgically implanted with EEG radio-telemetry transmitters, and qEEG was measured after vehicle or drug administration. The relative power for a number of frequency bands was determined. Ketamine and lanicemine increased relative gamma power, whereas the NR2B NAMs traxoprodil and BMT-108908 had no effect. Robust decreases in beta power were elicited by ketamine, traxoprodil and BMT-108908; and these agents also produced decreases in alpha power and increases in delta power at the doses tested. These results suggest that measurement of power spectra in the beta and delta bands may represent a translational pharmacodynamic biomarker to demonstrate functional effects of NR2B NAMs. The results of these studies may help guide the selection of qEEG measures that can be incorporated into early clinical evaluation of NR2B NAMs in healthy humans. PMID:27035340

  3. Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors

    SciTech Connect

    Shi, Wen-Zhu; Miao, Yu-Liang; Guo, Wen-Zhi; Wu, Wei; Li, Bao-Wei; An, Li-Na; Fang, Wei-Wu; Mi, Wei-Dong

    2014-04-25

    Highlights: • Leptin promotes the proliferation of neural stem cells isolated from embryonic mouse hippocampus. • Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation. • The effects of leptin are partially mediated by upregulating NR2B subunits. - Abstract: Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation of hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors.

  4. Inhibition of NR2B-Containing N-methyl-D-Aspartate Receptors (NMDARs) in Experimental Autoimmune Encephalomyelitis, a Model of Multiple Sclerosis

    PubMed Central

    Farjam, Mojtaba; Beigi Zarandi, Faegheh Baha'addini; Farjadian, Shirin; Geramizadeh, Bita; Nikseresht, Ali Reza; Panjehshahin, Mohammad Reza

    2014-01-01

    Neurodegeneration is the pathophysiological basis for permanent neurological disabilities in multiple sclerosis (MS); thus neuroprotection is emerging as a therapeutic approach in MS research. Modulation of excitotoxicity by inhibition of NMDARs has been suggested for neuroprotection, but selective antagonisation of the NR2B subtype of these receptors, a subtype believed to play a more pivotal role in neurodegeneration, has not been tested in MS. In this study inhibition of NR2B-containing NMDAR was evaluated on the animal model of MS, experimental autoimmune encephalomyelitis (EAE). EAE induction was done using MOG in C57BL/6 mice. Therapeutic administration of different doses of highly selective NR2B-containing NMDAR inhibitor (RO25-6981) was compared with memantine (non-selective NMDAR antagonist) and vehicle. Neurological deficits in EAE animals were more efficiently decreased by selective inhibition of NR2B-containing NMDARs. Histological studies of the spinal cords also showed decreased inflammation, myelin degradation and neuro-axonal degeneration when RO25-6981was administered with higher doses. The effects were dose dependent. Regarding the role of NR2B-containing NMDARs in excitotoxicity, selective inhibition of these receptor subtypes seems to modulate the neurological disabilities and pathological changes in EAE. Further elucidation of the exact mechanism of action as well as more experimental studies can suggest NR2B-containing NMDAR inhibition as a potentially effective treatment strategy for slowing down the clinical deterioration of disability in MS. PMID:25237366

  5. Activation of GRs-Akt-nNOs-NR2B signaling pathway by second dose GR agonist contributes to exacerbated hyperalgesia in a rat model of radicular pain.

    PubMed

    Zhang, Jing; Zhang, Wei; Sun, Yu'e; Liu, Yue; Song, Lihua; Ma, Zhengliang; Gu, Xiaoping

    2014-06-01

    Central Akt, neuronal nitric oxide synthase (nNOS) and N-methyl-D-aspartate receptor subunit 2B (NR2B) play key roles in the development of neuropathic pain. Here we investigate the effects of glucocorticoid receptors (GRs) on the expression and activation of spinal Akt, nNOS and NR2B after chronic compression of dorsal root ganglia (CCD). Thermal hyperalgesia test and mechanical allodynia test were used to measure rats after intrathecal injection of GR antagonist mifepristone or GR agonist dexamethasone for 21 days postoperatively. Expression of spinal Akt, nNOS, NR2B and their phosphorylation state after CCD was examined by western blot. The effects of intrathecal treatment with dexamethasone or mifepristone on nociceptive behaviors and the corresponding expression of Akt, nNOS and NR2B in spinal cord were also investigated. Intrathecal injection of mifepristone or dexamethasone inhibited PWMT and PWTL in CCD rats. However, hyperalgesia was induced by intrathecal injection of dexamethasone on days 12 to 14 after surgery. Treatment of dexamethasone increased the expression and phosphorylation levels of spinal Akt, nNOS, GR and NR2B time dependently, whereas administration of mifepristone downregulated the expression of these proteins significantly. GRs activated spinal Akt-nNOS/NR2B pathway play important roles in the development of neuropathic pain in a time-dependent manner.

  6. The preventive effect of NR2B and NR2D-containing NMDAR antagonists on Aβ-induced LTP disruption in the dentate gyrus of rats.

    PubMed

    Zhang, Junfang; Wang, Chuang; Deng, Tianxiang; Xue, Zhancheng; Chen, Xiaowei; Chang, Lan; Wang, Qinwen

    2013-12-01

    Amyloid β-protein (Aβ) in the brain of Alzheimer's disease (AD) potently inhibits the synaptic plasticity subsequently causing the cognitive deficits. Long-term potentiation (LTP) of synaptic transmission is thought to be an important cellular mechanism underlying memory formation. Different NR2 subunits are involved in NMDA receptor-dependent LTP. In the present study, we investigated the roles of NR2B and NR2D-containing NMDAR on Aβ(1-42)-induced LTP deficits in the hippocampal slices of rats by using selective NMDAR antagonists. First, we found that Aβ(1-42) significantly inhibited the LTP in the dentate gyrus of slices as reported before. Following that the Aβ(1-42)-induced LTP inhibition was prevented by the pre-perfusion of the specific NR2B-containing NMDAR antagonists ifenprodil (approximately >200-fold selectivity for NR2B) and Ro25-6981 (>3,000-fold selectivity for NR2B), as well as PPDA, a specific NR2D receptor antagonist. Meanwhile, the antagonists on their own had no or only partial effects on the normal LTP in the same dose condition. These findings not only support the effects of NR2B and NR2D subunits on Aβ(1-42)-induced LTP deficits, but also imply that preferentially targeting NR2B- and NR2D-containing NMDARs may provide an effective means to prevent cognitive deficits in the early AD.

  7. Kinesin superfamily protein 17 contributes to the development of bone cancer pain by participating in NR2B transport in the spinal cord of mice.

    PubMed

    Liu, Ming; Liu, Yue; Hou, Bailing; Bu, Dan; Shi, Linyu; Gu, Xiaoping; Ma, Zhengliang

    2015-03-01

    Τreatment of bone cancer pain remains a challenge, while the mechanisms causing the pain remain elusive. We demonstrated that the expression of the N‑methyl‑D‑aspartate (NMDA) receptor NR2B subunit was upregulated in mice with bone cancer pain. Kinesin superfamily protein 17 (KIF17), a recently characterized member of the kinesin superfamily proteins, has been demonstrated to transport and deliver the NR2B subunit to dendrites in mammalian neurons. In the present study, we induced bone cancer pain via femur bone cavity osteosarcoma NCTC 2472 tumor cell implantation (TCI) in mice. The results showed that TCI in mice increased the number of spontaneous flinches, mechanical allodynia events, expression of spinal KIF17 and NR2B subunits. Intrathecal administration of KIF17 antisense oligodeoxynucleotide (ODN) attenuated the behavioral signs of bone cancer pain and suppressed the increased expression of NR2B induced by TCI. In addition, KIF17 binds to a protein complex that contains mLin‑10 to transport NR2B, and we determined that the increase of mLin‑10 was suppressed following admini-stration. Thus, these findings suggested that KIF17 contributed to the development of bone cancer pain in the spinal cord through NR2B transport and that mLin‑10 may also play a role in pain development.

  8. Negative regulation of REST on NR2B in spinal cord contributes to the development of bone cancer pain in mice.

    PubMed

    Wang, Dan; Yu, Jianbo

    2016-12-20

    In this study, C3H/HeNCrlVr mice are implanted with sarcoma NCTC 2472 cells into the intramedullary space of the femur to induce ongoing bone cancer-related pain behaviors. During the progress of the bone cancer pain, the down-regulation in spinal REST (Neuron-restrictive silencer factor, NRSF/REST) with concomitant up-regulation in spinal NR2B (2B subunit of N-methyl-D-aspartate receptor, NR2B) protein expression are observed at days 5, 7, 10 and 14 post-inoculation. Immunofluorescence assay shows that almost all of REST and NR2B-positive signals encompass NeuN (neuron-specific nuclear protein, a neuronal marker)-positive signals in spinal cord of sham and tumor-bearing mice. Different from previous researches involved in the main distribution of REST in neural progenitors, the expression of REST in mature neurons in spinal cord of adult mice is observed. Intrathecal administration of AS-ODN of REST at days 0, 2, 4 and 6 post-inoculation further enhances expression of spinal NR2B at day 7 post-inoculation, which suggests the reduced suppression of spinal REST on NR2B during the development of bone cancer pain. In summary, our study provides the evidence that the negative regulation of REST on NR2B in spinal cord takes part in the exacerbation of bone cancer pain.

  9. Inhibition of NR2B-Containing N-methyl-D-Aspartate Receptors (NMDARs) in Experimental Autoimmune Encephalomyelitis, a Model of Multiple Sclerosis.

    PubMed

    Farjam, Mojtaba; Beigi Zarandi, Faegheh Baha'addini; Farjadian, Shirin; Geramizadeh, Bita; Nikseresht, Ali Reza; Panjehshahin, Mohammad Reza

    2014-01-01

    Neurodegeneration is the pathophysiological basis for permanent neurological disabilities in multiple sclerosis (MS); thus neuroprotection is emerging as a therapeutic approach in MS research. Modulation of excitotoxicity by inhibition of NMDARs has been suggested for neuroprotection, but selective antagonisation of the NR2B subtype of these receptors, a subtype believed to play a more pivotal role in neurodegeneration, has not been tested in MS. In this study inhibition of NR2B-containing NMDAR was evaluated on the animal model of MS, experimental autoimmune encephalomyelitis (EAE). EAE induction was done using MOG in C57BL/6 mice. Therapeutic administration of different doses of highly selective NR2B-containing NMDAR inhibitor (RO25-6981) was compared with memantine (non-selective NMDAR antagonist) and vehicle. Neurological deficits in EAE animals were more efficiently decreased by selective inhibition of NR2B-containing NMDARs. Histological studies of the spinal cords also showed decreased inflammation, myelin degradation and neuro-axonal degeneration when RO25-6981was administered with higher doses. The effects were dose dependent. Regarding the role of NR2B-containing NMDARs in excitotoxicity, selective inhibition of these receptor subtypes seems to modulate the neurological disabilities and pathological changes in EAE. Further elucidation of the exact mechanism of action as well as more experimental studies can suggest NR2B-containing NMDAR inhibition as a potentially effective treatment strategy for slowing down the clinical deterioration of disability in MS.

  10. An NR2B-Dependent Decrease in the Expression of trkB Receptors Precedes the Disappearance of Dopaminergic Cells in Substantia Nigra in a Rat Model of Presymptomatic Parkinson's Disease

    PubMed Central

    Riquelme, Eduardo; Abarca, Jorge; Campusano, Jorge M.; Bustos, Gonzalo

    2012-01-01

    Compensatory changes occurring during presymptomatic stages of Parkinson's disease (PD) would explain that the clinical symptoms of the disease appear late, when the degenerative process is quite advanced. Several data support the proposition that brain-derived neurotrophic factor (BDNF) could play a role in these plastic changes. In the present study, we evaluated the expression of the specific BDNF receptor, trkB, in a rat model of presymptomatic PD generated by intrastriatal injection of the neurotoxin 6-OHDA. Immunohistochemical studies revealed a decrease in trkB expression in SN pars compacta (SNc) seven days after 6-OHDA injection. At this time point, no change in the number of tyrosine hydroxylase (TH) immunoreactive (TH-IR) cells is detected, although a decrease is evident 14 days after neurotoxin injection. The decrease in TH-positive cells and trkB expression in SNc was significantly prevented by systemic administration of Ifenprodil, a specific antagonist of NR2B-containing NMDA receptors. Therefore, an NR2B-NMDA receptor-dependent decrease in trkB expression precedes the disappearance of TH-IR cells in SNc in response to 6-OHDA injection. These results support the idea that a functional coupling between NMDA receptors and BDNF/trkB signalling may be important for the maintenance of the dopaminergic phenotype in SNc during presymptomatic stages of PD. PMID:22720191

  11. Spinal SIRPα1-SHP2 interaction regulates spinal nerve ligation-induced neuropathic pain via PSD-95-dependent NR2B activation in rats.

    PubMed

    Peng, Hsien-Yu; Chen, Gin-Den; Lai, Cheng-Yuang; Hsieh, Ming-Chun; Lin, Tzer-Bin

    2012-05-01

    The fact that neuropathic pain mechanisms are not well understood is a major impediment in the development of effective clinical treatments. We examined whether the interaction between signal regulatory protein alpha 1 (SIRPα1) and Src homology-2 domain-containing protein tyrosine phosphatase 2 (SHP2), and the downstream spinal SHP2/postsynaptic density 95 (PSD-95)/N-methyl-d-aspartate receptor NR2B subunit signaling cascade play a role in neuropathic pain. Following spinal nerve ligation (L5), we assessed tactile allodynia using the von Frey filament test and analyzed dorsal horn samples (L4-5) by Western blotting, reverse transcription polymerase chain reaction, coimmunoprecipitation, and immunofluorescence. Nerve ligation induced allodynia, SIRPα1, SHP2, phosphorylated SHP2 (pSHP2), and phosphorylated NR2B (pNR2B) expression, and SHP2-PSD-95, pSHP2-PSD-95, PSD-95-NR2B, and PSD-95-pNR2B coimmunoprecipitation in the ipsilateral dorsal horn. In allodynic rats, injury-induced SHP2 immunoreactivity was localized in the ipsilateral dorsal horn neurons and coincident with PSD-95 and NR2B immunoreactivity. SIRPα1 silencing using small interfering RNA (siRNA; 1, 3, or 5μg/rat for 7days) prevented injury-induced allodynia and the associated changes in protein expression, phosphorylation, and coimmunoprecipitation. Intrathecal administration of NSC-87877 (an SHP2 antagonist; 1, 10, or 100μM/rat) and SIRPα1-neutralizing antibodies (1, 10, or 30μg/rat) suppressed spinal nerve ligation-induced allodynia, spinal SHP2 and NR2B phosphorylation, and SHP2/phosphorylated SHP2-PSD-95 and PSD-95-NR2B/phosphorylated NR2B coprecipitation. SHP2 siRNA led to similar effects as the NSC-87877 and SIRPα1 antibody treatments, except it prevented the allodynia-associated spinal SHP2 expression. In conclusion, our results suggest that a spinal SIRPα1-SHP2 interaction exists that subsequently triggers SHP2/PSD-95/NR2B signaling, thereby playing a role in neuropathic pain development.

  12. Downregulation of the spinal NMDA receptor NR2B subunit during electro-acupuncture relief of chronic visceral hyperalgesia.

    PubMed

    Liu, Hongping; Zhang, Yuhua; Qi, Debo; Li, Weimin

    2017-01-01

    The involvement of spinal NR2B, a N-methyl-D-aspartate (NMDA) receptor subunit, in the therapeutic effect of electro-acupuncture (EA) on chronic visceral hyperalgesia was investigated. Chronic visceral hyperalgesia was induced using an irritable bowel syndrome (IBS) model in rats. Graded colorectal distention (CRD) stimuli at strengths of 20, 40, 60 and 80 mmHg were applied, and behavioral tests were performed to measure the abdominal withdrawal reflex (AWR) in response to the CRD stimuli and assess the severity of the visceral hyperalgesia. Rats were randomly divided into four groups: normal intact (control) group, IBS model (model) group, EA-treated IBS rats (EA) group and sham EA-treated IBS rats (sham EA) group. For the EA treatment, electric stimuli were applied through needles inserted into two acupoints [Zu-san-li (ST-36) and Shang-ju-xu (ST-37)] in both hind limbs, while the sham EA treatment consisted of only the insertion of needles into these same acupoints without an application of electric stimuli. Our results showed that AWR scores of the model group responding to CRD stimuli of 20, 40, 60 and 80 mmHg were significantly increased. These increased scores subsequently decreased following EA treatment (P < 0.05) compared with those for the other groups. The expression of NR2B in the superficial laminae (SDH, laminae I and II), nucleus proprius (NP, laminae III and IV), neck of the dorsal horn (NECK, laminae V and VI) and central canal region (lamina X) at thoracolumbar (T13-L2) and lumbosacral (L6-S2) segmental level significantly increased in the model group versus the control group (P < 0.05) and significantly decreased after EA treatment (P < 0.05). There were no significant changes in neither AWR scores nor expression of the NR2B subunit in these spinal regions after the sham EA treatment. These results confirm that EA can relieve chronic visceral hyperalgesia in IBS model rats and suggest that such an effect is possibly mediated through the

  13. Phosphorylated CaMKII post-synaptic binding to NR2B subunits in the anterior cingulate cortex mediates visceral pain in visceral hypersensitive rats.

    PubMed

    Li, Ying; Zhang, Xu; Liu, Haiyan; Cao, Zhijun; Chen, Shengliang; Cao, Bing; Liu, Jin

    2012-05-01

    The NR2B subunit of NMDA receptor in the anterior cingulate cortex (ACC) is up-regulated in viscerally hypersensitive (VH) rats induced by colonic anaphylaxis. It plays a critical role in modulation of ACC sensitization and visceral pain responses. Given the key role of calcium/calmodulin-dependent protein kinase II (CaMKII) in synaptic plasticity and behavior learning and memory, we hypothesize that phosphorylation of CaMKII binding to NR2B mediates visceral pain in VH states. We performed in vivo electroporation of CaMKII siRNA produced inhibition of colorectal distension-induced visceromotor response in the VH rats. The NR2B, CaMKII and P-CaMKII-Thr²⁸⁶ protein levels were increased in 180%, 220% and 304% fold in the post-synaptic density (PSD) fraction in VH rats separately. Western blotting following co-immunoprecipitation showed that P-CaMKII-Thr²⁸⁶ bound to NR2B in the PSD, which was increased to 267% of control in VH rats. Administration of CaMKII antagonist Antennapedia-CaMKIINtide suppressed visceromotor response in VH rats in parallel with decrease of NR2B levels and reduction of the NR2B-P-CaMKII-Thr²⁸⁶ protein complex in PSD. In conclusion, CaMKII is a critical signaling molecule in the ACC glutamatergic synaptic transmission and phosphorylation of CaMKII at Thr286, which binds to NR2B subunit at post-synaptic site, modulates visceral pain in viscerally hypersensitive state.

  14. Histone H3K9 modifications are a local chromatin event involved in ethanol-induced neuroadaptation of the NR2B gene.

    PubMed

    Qiang, Mei; Denny, Ashley; Lieu, Mai; Carreon, Stephanie; Li, Ji

    2011-09-01

    Expression of the NMDA receptor 2B (NR2B) gene is upregulated following chronic intermittent ethanol (CIE) treatment and withdrawal, which underlies behavioral alterations in addiction. The goal of this study was to characterize the changes of histone modifications induced by CIE treatment and its subsequent removal associated to the upregulation of NR2B gene transcription. To investigate the involvement of histone acetylation in the effect of ethanol on the NR2B gene, we examined the influence of CIE on histone acetylation in the 5' regulatory region of NR2B using a qChIP assay. CIE treatment and its subsequent removal produced a remarkable and selected increase in histone H3K9 acetylation. Interestingly, the majority of the increased H3K9 acetylation occurred after ethanol removal, which was coincident with a decrease in H3K9 methylation in the same time duration. Further examination of the mechanisms of ethanol-induced alterations on the histone modifications revealed that CIE-induced acetylation of H3K9 was not due to the changes in global enzyme activities or the expression of histone acetyltransferases (HATs) and deacetylase (HDACs). Instead, we found a significant downregulation in some histone methyltransferases (HMTs) at both the global level and the local chromatin of the NR2B gene following CIE treatment. Moreover, our experiments also indicated a decrease of G9a, Suv39 h1 and HDAC1-3 in the chromatin of the NR2B gene promoter, which may be responsible for the altered H3K9 modifications. Taken together, the findings suggest a mechanism where the changes in H3K9 modifications in the local chromatin of the NR2B gene underlie alcohol-induced neuroadaptation.

  15. The inhibitor of calcium/calmodulin-dependent protein kinase II KN93 attenuates bone cancer pain via inhibition of KIF17/NR2B trafficking in mice.

    PubMed

    Liu, Yue; Liang, Ying; Hou, Bailing; Liu, Ming; Yang, Xuli; Liu, Chenglong; Zhang, Juan; Zhang, Wei; Ma, Zhengliang; Gu, Xiaoping

    2014-09-01

    The N-methyl-d-aspartate receptor (NMDAR) containing subunit 2B (NR2B) is critical for the regulation of nociception in bone cancer pain, although the precise molecular mechanisms remain unclear. KIF17, a kinesin motor, plays a key role in the dendritic transport of NR2B. The up-regulation of NR2B and KIF17 transcription results from an increase in phosphorylated cAMP-response element-binding protein (CREB), which is activated by calcium/calmodulin-dependent protein kinase II (CaMKII). In this study, we hypothesized that CaMKII-mediated KIF17/NR2B trafficking may contribute to bone cancer pain. Osteosarcoma cells were implanted into the intramedullary space of the right femurs of C3H/HeJ mice to induce progressive bone cancer-related pain behaviors. The expression of spinal t-CaMKII, p-CaMKII, NR2B and KIF17 after inoculation was also evaluated. These results showed that inoculation of osteosarcoma cells induced progressive bone cancer pain and resulted in a significant up-regulation of p-CaMKII, NR2B and KIF17 expression after inoculation. Intrathecal administration of KN93, a CaMKII inhibitor, down-regulated these three proteins and attenuated bone cancer pain in a dose- and time-dependent manner. These findings indicated that CaMKII-mediated KIF17/NR2B trafficking may contribute to bone cancer pain, and inhibition of CaMKII may be a useful alternative or adjunct therapy for relieving cancer pain.

  16. N-methyl-D-aspartate receptor NR2B subunit involved in depression-like behaviours in lithium chloride-pilocarpine chronic rat epilepsy model.

    PubMed

    Peng, Wei-Feng; Ding, Jing; Li, Xin; Fan, Fan; Zhang, Qian-Qian; Wang, Xin

    2016-01-01

    Depression is a common comorbidity in patients with epilepsy with unclear mechanisms. This study is to explore the role of glutamate N-methyl-D-aspartate (NMDA) receptor NR1, NR2A and NR2B subunits in epilepsy-associated depression. Lithium chloride (Licl)-pilocarpine chronic rat epilepsy model was established and rats were divided into epilepsy with depression (EWD) and epilepsy without depression (EWND) subgroups based on forced swim test. Expression of NMDA receptor NR1, NR2A and NR2B subunits was measured by western blot and immunofluorescence methods. The immobility time (IMT) was significantly greater in Licl-pilocarpine model group than in Control group, which was also greater in EWD group than in EWND group. No differences of spontaneous recurrent seizure (SRS) counts over two weeks and latency were found between EWD and EWND groups. The number of NeuN positive cells was significantly less in Licl-pilocarpine model group than in Control group, but had no difference between EWD and EWND groups. The ratios of phosphorylated NR1 (p-NR1)/NR1 and p-NR2B/NR2B were significantly greater in the hippocampus in EWD group than in EWND group. Moreover, the expression of p-NR1 and p-NR2B in the CA1 subfield of hippocampus were both greater in Licl-pilocarpine model group than Control group. Selective blockage of NR2B subunit with ifenprodil could alleviate depression-like behaviours of Licl-pilocarpine rat epilepsy model. In conclusion, glutamate NMDA receptor NR2B subunit was involved in promoting depression-like behaviours in the Licl-pilocarpine chronic rat epilepsy model and might be a target for treating epilepsy-associated depression.

  17. Blockade of NR2B-Containing NMDA Receptors Prevents BDNF Enhancement of Glutamatergic Transmission in Hippocampal Neurons

    PubMed Central

    Crozier, Robert A.; Black, Ira B.; Plummer, Mark R.

    1999-01-01

    Application of brain-derived neurotrophic factor (BDNF) to hippocampal neurons has profound effects on glutamatergic synaptic transmission. Both pre- and postsynaptic actions have been identified that depend on the age and type of preparation. To understand the nature of this diversity, we have begun to examine the mechanisms of BDNF action in cultured dissociated embryonic hippocampal neurons. Whole-cell patch-clamp recording during iontophoretic application of glutamate revealed that BDNF doubled the amplitude of induced inward current. Coexposure to BDNF and the NMDA receptor antagonist AP-5 markedly reduced, but did not entirely prevent, the increase in current. Coexposure to BDNF and ifenprodil, an NR2B subunit antagonist, reproduced the response observed with AP-5, suggesting BDNF primarily enhanced activity of NR2B-containing NMDA receptors with a lesser effect on non-NMDA receptors. Protein kinase involvement was confirmed with the broad spectrum inhibitor staurosporine, which prevented the response to BDNF. PKCI19-31 and H-89, selective antagonists of PKC and PKA, had no effect on the response to BDNF, whereas autocamtide-2-related inhibitory peptide, an antagonist of CaM kinase II, reduced response magnitude by 60%. These results demonstrate the predominant role of a specific NMDA receptor subtype in BDNF modulation of hippocampal synaptic transmission. PMID:10492007

  18. Multivalent interactions of calcium/calmodulin-dependent protein kinase II with the postsynaptic density proteins NR2B, densin-180, and alpha-actinin-2.

    PubMed

    Robison, A J; Bass, Martha A; Jiao, Yuxia; MacMillan, Leigh B; Carmody, Leigh C; Bartlett, Ryan K; Colbran, Roger J

    2005-10-21

    Dendritic calcium/calmodulin-dependent protein kinase II (CaMKII) is dynamically targeted to the synapse. We show that CaMKIIalpha is associated with the CaMKII-binding proteins densin-180, the N-methyl-D-aspartate receptor NR2B subunit, and alpha-actinin in postsynaptic density-enriched rat brain fractions. Residues 819-894 within the C-terminal domain of alpha-actinin-2 constitute the minimal CaMKII-binding domain. Similar amounts of Thr286-autophosphorylated CaMKIIalpha holoenzyme [P-T286]CaMKII bind to alpha-actinin-2 as bind to NR2B (residues 1260-1339) or to densin-180 (residues 1247-1495) in glutathione-agarose cosedimentation assays, even though the CaMKII-binding domains share no amino acid sequence similarity. Like NR2B, alpha-actinin-2 binds to representative splice variants of each CaMKII gene (alpha, beta, gamma, and delta), whereas densin-180 binds selectively to CaMKIIalpha. In addition, C-terminal truncated CaMKIIalpha monomers can interact with NR2B and alpha-actinin-2, but not with densin-180. Soluble alpha-actinin-2 does not compete for [P-T286]CaMKII binding to immobilized densin-180 or NR2B. However, soluble densin-180, but not soluble NR2B, increases CaMKII binding to immobilized alpha-actinin-2 by approximately 10-fold in a PDZ domain-dependent manner. A His6-tagged NR2B fragment associates with GST-densin or GST-actinin but only in the presence of [P-T286]CaMKII. Similarly, His6-tagged densin-180 or alpha-actinin fragments associate with GST-NR2B in a [P-T286]CaMKII-dependent manner. In addition, GST-NR2B and His6-tagged alpha-actinin can bind simultaneously to monomeric CaMKII subunits. In combination, these data support a model in which [P-T286]CaMKIIalpha can simultaneously interact with multiple dendritic spine proteins, possibly stabilizing the synaptic localization of CaMKII and/or nucleating a multiprotein synaptic signaling complex.

  19. Intrathecal baclofen, a GABAB receptor agonist, inhibits the expression of p-CREB and NR2B in the spinal dorsal horn in rats with diabetic neuropathic pain.

    PubMed

    Liu, Peng; Guo, Wen-Ya; Zhao, Xiao-Nan; Bai, Hui-Ping; Wang, Qian; Wang, Xiu-Li; Zhang, Ying-Ze

    2014-08-01

    This study aimed to investigate the effect of baclofen, a γ-aminobutyric acid B (GABAB) receptor agonist, on the expression of p-CREB and NR2B in the spinal dorsal horn of rats with diabetic neuropathic pain (DNP). The DNP rats, which were successfully induced with streptozocin, were distributed among 3 groups that were treated with saline (D1 group), baclofen (D2 group), or CGP55845 + baclofen (D3 group) continuously for 4 days. The rats induced with saline and subsequently treated with saline were used as controls (C group). The times for the paw withdrawal threshold and thermal withdrawal latency of the D1 group were lower than those for the C group, and were significantly increased after baclofen treatment, but not when GABA receptor was pre-blocked with CGP55845 (D3 group). Increased protein expression levels of NR2B and p-CREB and mRNA levels of NR2B were found in the D1 group when compared with the controls. Baclofen treatment significantly suppressed their expression, bringing it close to the levels of controls. However, in the D3 group, the expression of p-CREB and NR2B were still significantly higher than that of the controls. Activation of GABAB receptor by baclofen attenuates diabetic neuropathic pain, which may partly be accomplished via down-regulating the expression of p-CREB and NR2B.

  20. Intrathecal injection of selected peptide Myr-RC-13 attenuates bone cancer pain by inhibiting KIF17 and NR2B expression.

    PubMed

    Ni, Kun; Zhou, Yu; Sun, Yu-e; Liu, Yue; Gu, Xiao-ping; Ma, Zheng-liang

    2014-07-01

    Although bone cancer pain is a common intractable clinical symptom, its underlying mechanisms are still elusive. Accumulating evidence reveals that the N-methyl-D-aspartate (NMDA) receptor containing a 2B subunit (NR2B) in the spinal cord contributes to bone cancer pain. Our preliminary study demonstrated that intrathecal injection of fusion peptide Myr-RC-13 could disrupt spinal KIF17/mLin10 interaction, which is an essential component of KIF17-mediated NR2B transport. Here we report a means by infusion of the selected peptide Myr-RC-13 intrathecally to attenuate bone cancer pain. The results showed that inoculation of fibrosarcoma NCTC 2472 cells into the femur cavity of C3H/HeJ mice induced progressive bone cancer pain and resulted in up-regulation of KIF17 and NR2B in the spinal cord. In addition, repetitive spinal delivery of Myr-RC-13 relieved bone cancer-related mechanical allodynia and spontaneous pain behaviors, and down-regulated expression of spinal KIF17 and NR2B. Finally, our results demonstrated that selected peptide Myr-RC-13 was able to attenuate bone cancer pain via decreasing spinal KIF17 and NR2B expressions. Therefore, selected peptide Myr-RC-13 might be a potential analgesic strategy for bone cancer pain.

  1. Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors.

    PubMed

    Shi, Wen-Zhu; Miao, Yu-Liang; Guo, Wen-Zhi; Wu, Wei; Li, Bao-Wei; An, Li-Na; Fang, Wei-Wu; Mi, Wei-Dong

    2014-04-25

    Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation of hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors.

  2. Gene silencing of NR2B-containing NMDA receptor by intrathecal injection of short hairpin RNA reduces formalin-induced nociception in C57BL/6 mouse.

    PubMed

    Zhang, Rao-Xiang; Yan, Xue-Bin; Gu, Yong-Hong; Huang, Dong; Gan, Li; Han, Rui; Huang, Li-Hua

    2013-09-01

    Spinal NR2B-containing N-methyl-D-aspartate receptors (NR2B) play a critical role in the formation of central sensitization and persistent pain. Previous studies show that gene silencing of the spinal NR2B subunit by small interfering RNA (siRNA) could alleviate nociception in animals. The siRNA is a 19- to 23-nt RNA duplex, which can be synthesized in vitro or derived from short hairpin RNAs (shRNAs). In the present study, we investigated whether intrathecal injection of shRNAs targeting NR2B (GRIN2B shRNA) could affect nociception on formalin-induced pain in mice. Our results showed that intrathecal injection of GRIN2B shRNA could decrease NR2B mRNA and protein expression levels and hence effectively relieve formalin-induced nociception in mice, suggesting that intrathecal delivery of GRIN2B shRNA can be an efficient way to silence the target gene and provide new insights into the treatment of chronic pain.

  3. [Roles and expressions of the NMDA receptor subunits (NR2A and NR2B) in visual cortex area of kittens with the normal visual development and anisometropic amblyopia].

    PubMed

    Li, Haiwei; Liu, Longqian; Liu, Xuyang

    2011-04-01

    In order to understand the roles of the other subunits, we investigated expression of the NMDA receptor subunits (NR2A and NR2B) in visual cortex of normal and anisometropic amblyopia kittens with different ages in the present study. We examined the expressions of NR2A and NR2B in the visual cortex of the kittens by immunohistochemistry with polyclonal anti-NR2A antibody and anti-NR2B antibody, respectively. Using immunohisto-chemical Streptavidin Perosidase (SP) method, we observed the dynamic changes of NR2A and NR2B with microscope and computer-assisted image analyses. We found that NR2A and NR2B remained low expression after the peak of the critical period of kitten visual development; compared with normal group of the same age, NR2A expresses low. However, the difference is not significant for NR2B before maturation period of visual development. NR2B rises after the maturation period of visual development. According to this, the component of NR2A and NR2B can be affected by anisometropia. This research suggests that the difference of NR2A and NR2B expressions may affect the formation of amblyopia.

  4. Dopamine-induced tyrosine phosphorylation of NR2B (Tyr1472) is essential for ERK1/2 activation and processing of novel taste information.

    PubMed

    David, Orit; Barrera, Iliana; Chinnakkaruppan, Adaikkan; Kaphzan, Hanoch; Nakazawa, Takanobu; Yamamoto, Tadashi; Rosenblum, Kobi

    2014-01-01

    Understanding the heterosynaptic interaction between glutamatergic and neuromodulatory synapses is highly important for revealing brain function in health and disease. For instance, the interaction between dopamine and glutamate neurotransmission is vital for memory and synaptic plasticity consolidation, and it is known to converge on extracellular signal-regulated kinase (ERK)-MAPK signaling in neurons. Previous studies suggest that dopamine induces N-methyl-D-aspartate (NMDA) receptor phosphorylation at the NR2B Y1472 subunit, influencing receptor internalization at the synaptic plasma membrane. However, it is unclear whether this phosphorylation is upstream to and/or necessary for ERK1/2 activation, which is known to be crucial for synaptic plasticity and memory consolidation. Here, we tested the hypothesis that tyrosine phosphorylation of NR2B at Y1472 is correlated with ERK1/2 activation by dopamine and necessary for it as well. We find that dopamine receptor D1, but not D2, activates ERK1/2 and leads to NR2BY1472 phosphorylation in the mature hippocampus and cortex. Moreover, our results indicate that NR2B Y1472 phosphorylation is necessary for ERK1/2 activation. Importantly, application of dopamine or the D1 receptor agonist SKF38393 to hippocampal slices from NR2B F1472 mutant mice did not result in ERK1/2 activation, suggesting this site is not only correlated with ERK1/2 activation by dopamine stimulation, but also necessary for it. In addition, NR2B F1472 mice show impairment in learning of attenuation of taste neophobia but not associative taste learning. Our study shows that the dopaminergic and glutamatergic transmission converge on the NMDA receptor itself, at the Y1472 site of the NR2B subunit, and that this convergence is essential for ERK1/2 activation in the mature brain and for processing new sensory information in the cortex.

  5. Thiol oxidation and altered NR2B/NMDA receptor functions in in vitro and in vivo pilocarpine models: implications for epileptogenesis.

    PubMed

    Di Maio, Roberto; Mastroberardino, Pier G; Hu, Xiaoping; Montero, Laura M; Greenamyre, J Timothy

    2013-01-01

    Hippocampal sclerosis, the main pathological sign of chronic temporal lobe epilepsy (TLE), is associated with oxidative injury, altered N-methyl d-aspartate receptor (NMDAR) stoichiometry, and loss of hippocampal neurons. However, the mechanisms that drive the chronic progression of TLE remain elusive. Our previous studies have shown that NADPH oxidase activation and ERK 1/2 phosphorylation are required for the up-regulation of the predominantly pre-synaptic NR2B subunit auto-receptor in both in vitro and in vivo pilocarpine (PILO) models of TLE. To provide further understanding of the cellular responses during the early-stages of hyper excitability, we investigated the role of oxidative damage and altered NR2B functions. In rat primary hippocampal cultures, we found that N-acetylcysteine (NAC) prevented PILO-mediated thiol oxidation, apoptosis, cell death and NR2B subunit over-expression. Interestingly, NAC did not block thiol oxidation when added to the neurons 6h after the PILO exposure, suggesting that disulfide formation could rapidly become an irreversible phenomenon. Moreover, NAC pre-treatment did not prevent PILO-induced NR2A subunit over-expression, a critical event in hippocampal sclerosis. Pre-treatment with the highly specific NR2B subunit inhibitor, ifenprodil, partially decreased PILO-mediated thiol oxidation and was not effective in preventing apoptosis and cell death. However, if acutely administered 48h after PILO exposure, ifenprodil blocked glutamate-induced aberrant calcium influx, suggesting the crucial role of NR2B over-expression in triggering neuronal hyper-excitability. Furthermore, ifenprodil treatment was able to prevent NR2A subunit over-expression by means of ERK1/2 phosphorylation. Our findings indicate oxidative stress and NR2B/NMDA signaling as promising therapeutic targets for co-treatments aimed to prevent chronic epilepsy following the seizure onset.

  6. Chronic Administration of Benzo(a)pyrene Induces Memory Impairment and Anxiety-Like Behavior and Increases of NR2B DNA Methylation

    PubMed Central

    Zhang, Wenping; Tian, Fengjie; Zheng, Jinping; Li, Senlin; Qiang, Mei

    2016-01-01

    Background Recently, an increasing number of human and animal studies have reported that exposure to benzo(a)pyrene (BaP) induces neurological abnormalities and is also associated with adverse effects, such as tumor formation, immunosuppression, teratogenicity, and hormonal disorders. However, the exact mechanisms underlying BaP-induced impairment of neurological function remain unclear. The aim of this study was to examine the regulating mechanisms underlying the impact of chronic BaP exposure on neurobehavioral performance. Methods C57BL mice received either BaP in different doses (1.0, 2.5, 6.25 mg/kg) or olive oil twice a week for 90 days. Memory and emotional behaviors were evaluated using Y-maze and open-field tests, respectively. Furthermore, levels of mRNA expression were measured by using qPCR, and DNA methylation of NMDA receptor 2B subunit (NR2B) was examined using bisulfate pyrosequencing in the prefrontal cortex and hippocampus. Results Compared to controls, mice that received BaP (2.5, 6.25 mg/kg) showed deficits in short-term memory and an anxiety-like behavior. These behavioral alterations were associated with a down-regulation of the NR2B gene and a concomitant increase in the level of DNA methylation in the NR2B promoter in the two brain regions. Conclusions Chronic BaP exposure induces an increase in DNA methylation in the NR2B gene promoter and down-regulates NR2B expression, which may contribute to its neurotoxic effects on behavioral performance. The results suggest that NR2B vulnerability represents a target for environmental toxicants in the brain. PMID:26901155

  7. Expression of NR2B in cerebellar granule cells specifically facilitates effect of motor training on motor learning.

    PubMed

    Jiao, Jianwei; Nakajima, Akira; Janssen, William G M; Bindokas, Vytautas P; Xiong, Xiaoli; Morrison, John H; Brorson, James R; Tang, Ya-Ping

    2008-02-27

    It is believed that gene/environment interaction (GEI) plays a pivotal role in the development of motor skills, which are acquired via practicing or motor training. However, the underlying molecular/neuronal mechanisms are still unclear. Here, we reported that the expression of NR2B, a subunit of NMDA receptors, in cerebellar granule cells specifically enhanced the effect of voluntary motor training on motor learning in the mouse. Moreover, this effect was characterized as motor learning-specific and developmental stage-dependent, because neither emotional/spatial memory was affected nor was the enhanced motor learning observed when the motor training was conducted starting at the age of 3 months old in these transgenic mice. These results indicate that changes in the expression of gene(s) that are involved in regulating synaptic plasticity in cerebellar granule cells may constitute a molecular basis for the cerebellum to be involved in the GEI by facilitating motor skill learning.

  8. Cleavage of the NR2B subunit amino terminus of N-methyl-D-aspartate (NMDA) receptor by tissue plasminogen activator: identification of the cleavage site and characterization of ifenprodil and glycine affinities on truncated NMDA receptor.

    PubMed

    Ng, Kay-Siong; Leung, How-Wing; Wong, Peter T-H; Low, Chian-Ming

    2012-07-20

    Thrombolysis using tissue plasminogen activator (tPA) has been the key treatment for patients with acute ischemic stroke for the past decade. Recent studies, however, suggest that this clot-busting protease also plays various roles in brain physiological and pathophysiological glutamatergic-dependent processes, such as synaptic plasticity and neurodegeneration. In addition, increasing evidence implicates tPA as an important neuromodulator of the N-methyl-d-aspartate (NMDA) receptors. Here, we demonstrate that recombinant human tPA cleaves the NR2B subunit of NMDA receptor. Analysis of NR2B in rat brain lysates and cortical neurons treated with tPA revealed concentration- and time-dependent degradation of NR2B proteins. Peptide sequencing studies performed on the cleaved-off products obtained from the tPA treatment on a recombinant fusion protein of the amino-terminal domain of NR2B revealed that tPA-mediated cleavage occurred at arginine 67 (Arg(67)). This cleavage is tPA-specific, plasmin-independent, and removes a predicted ~4-kDa fragment (Arg(27)-Arg(67)) from the amino-terminal domain of the NR2B protein. Site-directed mutagenesis of putative cleavage site Arg(67) to Ala(67) impeded tPA-mediated degradation of recombinant protein. This analysis revealed that NR2B is a novel substrate of tPA and suggested that an Arg(27)-Arg(67)-truncated NR2B-containing NMDA receptor could be formed. Heterologous expression of NR2B with Gln(29)-Arg(67) deleted is functional but exhibits reduced ifenprodil inhibition and increased glycine EC(50) with no change in glutamate EC(50). Our results confirmed NR2B as a novel proteolytic substrate of tPA, where tPA may directly interact with NR2B subunits leading to a change in pharmacological properties of NR2B-containing NMDA receptors.

  9. NR2A- and NR2B-Containing NMDA Receptors in the Prelimbic Medial Prefrontal Cortex Differentially Mediate Trace, Delay, and Contextual Fear Conditioning

    ERIC Educational Resources Information Center

    Gilmartin, Marieke R.; Kwapis, Janine L.; Helmstetter, Fred J.

    2013-01-01

    Activation of "N"-methyl-D-aspartate receptors (NMDAR) in the prelimbic medial prefrontal cortex (PL mPFC) is necessary for the acquisition of both trace and contextual fear memories, but it is not known how specific NR2 subunits support each association. The NR2B subunit confers unique properties to the NMDAR and may differentially…

  10. Conformationally constrained NR2B selective NMDA receptor antagonists derived from ifenprodil: Synthesis and biological evaluation of tetrahydro-3-benzazepine-1,7-diols.

    PubMed

    Tewes, Bastian; Frehland, Bastian; Schepmann, Dirk; Schmidtke, Kai-Uwe; Winckler, Thomas; Wünsch, Bernhard

    2010-11-15

    NR2B selective NMDA receptor antagonists with tetrahydro-3-benzazepine-1,7-diol scaffold have been designed by formal cleavage and reconstitution of the piperidine ring of the lead compound ifenprodil (1). The secondary amine 10 represents the central building block for the synthesis of more than 25 tetrahydro-3-benzazepin-1-ols. Generally 7-hydroxy derivatives display higher NR2B receptor affinities than the corresponding 7-benzyloxy compounds. A distance of four atoms (five bond lengths) between the basic amino group and the terminal aryl moiety led to highest NR2B affinity. 3-(4-Phenylbutyl)-2,3,4,5-tetrahydro-1H-3-benzazepine-1,7-diol (WMS-1410, 25) represents the most promising NR2B antagonist of this series showing a K(i)-value of 14nM. Compound 25 reveals excellent selectivity over more than 100 further relevant target proteins, antagonizes glutamate induced excitotoxicity (IC(50)=18.4nM) and is metabolically more stable than ifenprodil. Up to a dose of 100mg/kg 25 is well tolerated by mice and it shows dose dependent analgesic activity in the late neuropathic pain phase of the formalin assay.

  11. Bisphenol-A rapidly promotes dynamic changes in hippocampal dendritic morphology through estrogen receptor-mediated pathway by concomitant phosphorylation of NMDA receptor subunit NR2B

    SciTech Connect

    Xu Xiaohong Ye Yinping; Li Tao; Chen Lei; Tian Dong; Luo Qingqing; Lu Mei

    2010-12-01

    Bisphenol-A (BPA) is known to be a potent endocrine disrupter. Evidence is emerging that estrogen exerts a rapid influence on hippocampal synaptic plasticity and the dendritic spine density, which requires activation of NMDA receptors. In the present study, we investigated the effects of BPA (ranging from 1 to 1000 nM), focusing on the rapid dynamic changes in dendritic filopodia and the expressions of estrogen receptor (ER) {beta} and NMDA receptor, as well as the phosphorylation of NMDA receptor subunit NR2B in the cultured hippocampal neurons. A specific ER antagonist ICI 182,780 was used to examine the potential involvement of ERs. The results demonstrated that exposure to BPA (ranging from 10 to 1000 nM) for 30 min rapidly enhanced the motility and the density of dendritic filopodia in the cultured hippocampal neurons, as well as the phosphorylation of NR2B (pNR2B), though the expressions of NMDA receptor subunits NR1, NR2B, and ER{beta} were not changed. The antagonist of ERs completely inhibited the BPA-induced increases in the filopodial motility and the number of filopodia extending from dendrites. The increased pNR2B induced by BPA (100 nM) was also completely eliminated. Furthermore, BPA attenuated the effects of 17{beta}-estradiol (17{beta}-E{sub 2}) on the dendritic filopodia outgrowth and the expression of pNR2B when BPA was co-treated with 17{beta}-E{sub 2}. The present results suggest that BPA, like 17{beta}-E{sub 2}, rapidly results in the enhanced motility and density of dendritic filopodia in the cultured hippocampal neurons with the concomitant activation of NMDA receptor subunit NR2B via an ER-mediated signaling pathway. Meanwhile, BPA suppressed the enhancement effects of 17{beta}-E{sub 2} when it coexists with 17{beta}-E{sub 2}. These results provided important evidence suggesting the neurotoxicity of the low levels of BPA during the early postnatal development of the brain.

  12. NR2B phosphorylation at tyrosine 1472 in spinal dorsal horn contributed to N-methyl-D-aspartate-induced pain hypersensitivity in mice.

    PubMed

    Li, Shuai; Cao, Jing; Yang, Xian; Suo, Zhan-Wei; Shi, Lei; Liu, Yan-Ni; Yang, Hong-Bin; Hu, Xiao-Dong

    2011-11-01

    Calcium influx via N-methyl-D-aspartate (NMDA)-subtype glutamate receptors (NMDARs) regulates the intracellular trafficking of NMDARs, leading to long-lasting modification of NMDAR-mediated synaptic transmission that is involved in development, learning, and synaptic plasticity. The present study investigated the contribution of such NMDAR-dependent synaptic trafficking in spinal dorsal horn to the induction of pain hypersensitivity. Our data showed that direct activation of NMDARs by intrathecal NMDA application elicited pronounced mechanical allodynia in intact mice, which was concurrent with a specific increase in the abundance of NMDAR subunits NR1 and NR2B at the postsynaptic density (PSD)-enriched fraction. Selective inhibition of NR2B-containing NMDARs (NR2BR) by ifenprodil dose dependently attenuated the mechanical allodynia in NMDA-injected mice, suggesting the importance of NR2BR synaptic accumulation in NMDA-induced pain sensitization. The NR2BR redistribution at synapses after NMDA challenge was associated with a significant increase in NR2B phosphorylation at Tyr1472, a catalytic site by Src family protein tyrosine kinases (SFKs) that has been shown to prevent NR2B endocytosis. Intrathecal injection of a specific SFKs inhibitor, PP2, to block NR2B tyrosine phosphorylation eliminated NMDA-induced NR2BR synaptic expression and also attenuated the mechanical allodynia. These data suggested that activation of spinal NMDARs was able to accumulate NR2BR at synapses via SFK signaling, which might exaggerate NMDAR-dependent nociceptive transmission and contribute to NMDA-induced nociceptive behavioral hyperresponsiveness.

  13. Overactivation of NR2B-containing NMDA receptors through entorhinal-hippocampal connection initiates accumulation of hyperphosphorylated tau in rat hippocampus after transient middle cerebral artery occlusion.

    PubMed

    Xu, Cheng-Shi; Liu, An-Chun; Chen, Juan; Pan, Zhi-Yong; Wan, Qi; Li, Zhi-Qiang; Wang, Ze-Fen

    2015-08-01

    Middle cerebral artery occlusion (MCAO) induces secondary damages in the hippocampus that is remote from primary ischemic regions. Tau hyperphosphorylation is an important risk for neurodegenerative diseases. Increased tau phosphorylation has been identified in ischemic cortex, but little is known regarding the changes in the hippocampus. We showed that unilateral transient MCAO induced accumulation of hyperphosphorylated tau and concurrent dephosphorylation of glycogen synthase kinase-3β at Ser 9 in the ipsilateral hippocampus. These MCAO-induced changes were not reproduced when glutamatergic inputs from the entorhinal cortex to the hippocampus were transected; however, the changes were mimicked by intrahippocampal N-methyl-d-aspartate (NMDA) administration. Inhibition of NMDA receptor (NMDAR) subunit NR2B, but not NR2A activity in the hippocampus attenuated the accumulation of hyperphosphorylated tau and spatial cognitive impairment in MCAO rats. Together, our data suggest that overactivation of NR2B-containing NMDARs through entorhinal-hippocampal connection plays an important role in the accumulation of hyperphosphorylated tau in the hippocampus following MCAO. Glycogen synthase kinase-3β is an important protein kinase involved in NMDARs-mediated tau hyperphosphorylation. This study indicates that early inhibition of NR2B-containing NMDARs may represent a potential strategy to prevent or delay the occurrence of post-stroke dementia. Middle cerebral artery occlusion induces secondary damage in the hippocampus that is remote from primary ischemic regions. We propose that excessive activation of NR2B-containing NMDA receptors through entorhinal-hippocampal connection initiated the accumulation of hyperphosphorylated tau in the hippocampus, which subsequently induced cognitive deficit. This study provides new insights into the prospects of NR2B inhibition in stoke therapy.

  14. Vorinostat, a histone deacetylase inhibitor, facilitates fear extinction and enhances expression of the hippocampal NR2B-containing NMDA receptor gene.

    PubMed

    Fujita, Yosuke; Morinobu, Shigeru; Takei, Shiro; Fuchikami, Manabu; Matsumoto, Tomoya; Yamamoto, Shigeto; Yamawaki, Shigeto

    2012-05-01

    Histone acetylation, which alters the compact chromatin structure and changes the accessibility of DNA to regulatory proteins, is emerging as a fundamental mechanism for regulating gene expression. Histone deacetylase (HDAC) inhibitors increase histone acetylation and enhance fear extinction. In this study, we examined whether vorinostat, an HDAC inhibitor, facilitates fear extinction, using a contextual fear conditioning (FC) paradigm, in Sprague-Dawley rats. We found that vorinostat facilitated fear extinction. Next, the levels of global acetylated histone H3 and H4 were measured by Western blotting. We also assessed the effect of vorinostat on the hippocampal levels of NMDA receptor mRNA by real-time quantitative PCR (RT-PCR) and protein by Western blotting. 2 h after vorinostat administration, the levels acetylated histones and NR2B mRNA, but not NR1 or NR2A mRNA, were elevated in the hippocampus. The NR2B protein level was elevated 4 h after vorinostat administration. Last, we investigated the levels of acetylated histones and phospho-CREB (p-CREB) binding at the promoter of the NR2B gene using the chromatin immunoprecipitation (ChIP) assay followed by RT-PCR. The ChIP assay revealed increases in the levels of acetylated histones and they were accompanied by enhanced binding of p-CREB to its binding site at the promoter of the NR2B gene 2 h after vorinostat administration. These findings suggest that vorinostat increases the expression of NR2B in the hippocampus by enhancing histone acetylation, and this process may be implicated in fear extinction.

  15. Effects of L-3-n-butylphthalide on cognitive dysfunction and NR2B expression in hippocampus of streptozotocin (STZ)-induced diabetic rats.

    PubMed

    Li, Jie; Zhang, Songyun; Zhang, Lihui; Wang, Ruiying; Wang, Mian

    2015-01-01

    Diabetes mellitus is associated with rapid cognitive decline. Currently, there is no effective treatment for cognitive dysfunction induced by diabetes. L-3-n-Butylphthalide (L-NBP) is a nerve protective drug extracted from seeds of celery, which has been proved to improve learning and memory in vascular dementia animal models by improving microcirculation, protecting mitochondria and increasing long-term potentiation (LTP). NR2B, one of the subunits of N-methyl-D-aspartate receptor, has been proved to be an important factor for the formation of LTP. The study aimed to investigate the role of NR2B in cognitive dysfunction in the rats with type 1 diabetes and define the protective effects of L-NBP on cognition. A rat model of type 1 diabetes was established by a single intraperitoneal injection of streptozotocin at 60 mg/kg. Animals were randomly allocated to four groups: normal control (NC); diabetic control (DC); diabetic + low L-NBP (DL, administered L-NBP 60 mg/kg per day for 12 weeks); and diabetic + high L-NBP (DH, administered L-NBP 120 mg/kg per day, for 12 weeks). After 12 weeks, cognitive and memory changes were investigated in the Morris water maze. The expression of NR2B was assessed by real-time polymerase chain reaction, Western blotting, and immunohistochemistry. Our results indicated that the escape latency was significantly increased and the number of crossing platform was significantly decreased in DC group compared to NC group. Also, the expression of NR2B was significantly declined in DC group. However, compared to DC group, the expression of NR2B of the L-NBP-treated groups was significantly increased and the escape latency was shortened with the DH group being the most obvious. Therefore, L-NBP can improve the cognitive function by up-regulating the expression of NR2B in STZ-diabetic rats, which may provide the direction for future diabetic encephalopathy therapy.

  16. Copper-catalyzed amination of (bromophenyl)ethanolamine for a concise synthesis of aniline-containing analogues of NMDA NR2B antagonist ifenprodil.

    PubMed

    Bouteiller, Cédric; Becerril-Ortega, Javier; Marchand, Patrice; Nicole, Olivier; Barré, Louisa; Buisson, Alain; Perrio, Cécile

    2010-03-07

    An operationally simple and concise synthesis of anilinoethanolamines, as NMDA NR2B receptor antagonist ifenprodil analogues, was developed via a copper-catalyzed amination of the corresponding bromoarene. Coupling was achieved with linear primary alkylamines, alpha,omega-diamines, hexanolamine and benzophenone imine, as well as with aqueous ammonia, in good yields using CuI and N,N-diethylsalicylamide, 2,4-pentadione or 2-acetylcyclohexanone as catalytic systems. Amination with ethylene diamine was efficient even in the absence of an additive ligand, whereas no reaction occurred with ethanolamine whatever the conditions used. The anilinoethanolamines were evaluated as NR2B receptor antagonists in a functional inhibition assay. Aminoethylanilines displayed inhibition effects close to that of ifenprodil.

  17. Regulation of fear extinction versus other affective behaviors by discrete cortical scaffolding complexes associated with NR2B and PKA signaling.

    PubMed

    Corcoran, K A; Leaderbrand, K; Jovasevic, V; Guedea, A L; Kassam, F; Radulovic, J

    2015-10-13

    In patients suffering from post-traumatic stress disorder (PTSD), fear evoked by trauma-related memories lasts long past the traumatic event and it is often complicated by general anxiety and depressed mood. This poses a treatment challenge, as drugs beneficial for some symptoms might exacerbate others. For example, in preclinical studies, antagonists of the NR2B subunit of N-methyl-d-aspartate receptors and activators of cAMP-dependent protein kinase (PKA) act as potent antidepressants and anxiolytics, but they block fear extinction. Using mice, we attempted to overcome this problem by interfering with individual NR2B and PKA signaling complexes organized by scaffolding proteins. We infused cell-permeable Tat peptides that displaced either NR2B from receptor for activated C kinase 1 (RACK1), or PKA from A-kinase anchor proteins (AKAPs) or microtubule-associated proteins (MAPs). The infusions were targeted to the retrosplenial cortex, an area involved in both fear extinction of remotely acquired memories and in mood regulation. Tat-RACK1 and Tat-AKAP enhanced fear extinction, all peptides reduced anxiety and none affected baseline depression-like behavior. However, disruption of PKA complexes distinctively interfered with the rapid antidepressant actions of the N-methyl-D-aspartate receptors antagonist MK-801 in that Tat-MAP2 blocked, whereas Tat-AKAP completely inverted the effect of MK-801 from antidepressant to depressant. These effects were unrelated to the MK-801-induced changes of brain-derived neurotrophic factor messenger RNA levels. Together, the findings suggest that NR2B-RACK1 complexes specifically contribute to fear extinction, and may provide a target for the treatment of PTSD. AKAP-PKA, on the other hand, appears to modulate fear extinction and antidepressant responses in opposite directions.

  18. Identification of a Novel Rat NR2B Subunit Gene Promoter Region Variant and Its Association with Microwave-Induced Neuron Impairment.

    PubMed

    Wang, Li-Feng; Tian, Da-Wei; Li, Hai-Juan; Gao, Ya-Bing; Wang, Chang-Zhen; Zhao, Li; Zuo, Hong-Yan; Dong, Ji; Qiao, Si-Mo; Zou, Yong; Xiong, Lu; Zhou, Hong-Mei; Yang, Yue-Feng; Peng, Rui-Yun; Hu, Xiang-Jun

    2016-05-01

    Microwave radiation has been implicated in cognitive dysfunction and neuronal injury in animal models and in human investigations; however, the mechanism of these effects is unclear. In this study, single nucleotide polymorphism (SNP) sites in the rat GRIN2B promoter region were screened. The associations of these SNPs with microwave-induced rat brain dysfunction and with rat pheochromocytoma-12 (PC12) cell function were investigated. Wistar rats (n = 160) were exposed to microwave radiation (30 mW/cm(2) for 5 min/day, 5 days/week, over a period of 2 months). Screening of the GRIN2B promoter region revealed a stable C-to-T variant at nucleotide position -217 that was not induced by microwave exposure. The learning and memory ability, amino acid contents in the hippocampus and cerebrospinal fluid, and NR2B expression were then investigated in the different genotypes. Following microwave exposure, NR2B protein expression decreased, while the Glu contents in the hippocampus and CSF increased, and memory impairment was observed in the TT genotype but not the CC and CT genotypes. In PC12 cells, the effects of the T allele were more pronounced than those of the C allele on transcription factor binding ability, transcriptional activity, NR2B mRNA, and protein expression. These effects may be related to the detrimental role of the T allele and the protective role of the C allele in rat brain function and PC12 cells exposed to microwave radiation.

  19. NMDA receptor subunit expression in the supraoptic nucleus of adult rats: Dominance of NR2B and NR2D

    PubMed Central

    Doherty, Faye C; Sladek, Celia D

    2011-01-01

    The supraoptic nucleus (SON) of the hypothalamus contains magnocellular neurosecretory neurons (MNC) which synthesize and release the peptide hormones vasopressin and oxytocin. Glutamate is a prominent excitatory neurotransmitter in the SON and regulates MNC excitability. NMDA receptors (NMDAR), a type of ionotropic glutamate receptor, mediate synaptic plasticity of MNCs and are necessary for characteristic burst firing patterns which serve to maximize hormone release. NMDARs are di- or tri-heteromeric complexes of NR1 and NR2 subunits. Receptor properties depend on NR2 subunit composition and variable splicing of NR1. We investigated the expression profile of NR1 and NR2 subunits in the SON at the mRNA and protein levels, plus protein expression of NR1 splice variants in control and salt-loaded adult rats. There was robust mRNA expression of all subunits, with NR2D levels being the highest. At the protein level, NR1, NR2B and NR2D were robustly expressed, while NR2A was weakly expressed. NR2C protein was not detected with either of two antibodies. All four NR1 splice variant cassettes (N1, C1, C2, C2’) were detected in the SON, though NR1 N1 expression was too low for accurate analysis. Three days of salt-loading did not alter mRNA, protein or splice variant expression of NMDAR subunits in the SON. Robust NR2D protein expression has not been previously shown in MNCs, and is uncommon in the adult brain. Though the functional significance of this unusual expression profile is unknown, it may contribute to important physiological characteristics of SON neurons, such as burst firing and resistance to excitotoxicity. PMID:21397592

  20. Hydrogen-rich saline prevents remifentanil-induced hyperalgesia and inhibits MnSOD nitration via regulation of NR2B-containing NMDA receptor in rats.

    PubMed

    Zhang, L; Shu, R; Wang, H; Yu, Y; Wang, C; Yang, M; Wang, M; Wang, G

    2014-11-07

    Remifentanil administration may subsequently cause paradoxical hyperalgesia in animals and humans, but mechanisms remain unclear. Manganese superoxide dismutase (MnSOD) nitration and inactivation caused by generation of reactive oxygen species and activation of N-methyl-D-aspartate (NMDA) receptors are involved in the induction and maintenance of central neuropathic pain. Hydrogen which selectively removes superoxide has gained much attention in recent years. In this study, we investigated antinociceptive effects of hydrogen-rich saline (HRS) on remifentanil-induced postsurgical hyperalgesia in a rat model of incisional pain. HRS was injected intraperitoneally 10 min before remifentanil infusion (1 μg kg(-1) min(-1) for 60 min). A selective NR2B antagonist Ro25-6981 was used to investigate whether antihypernociception of HRS is associated with NMDA receptor (NMDAR). Nociception was evaluated by the paw withdrawal mechanical threshold and thermal latency respectively. Then we assessed MnSOD, NR2A and NR2B in spinal cord dorsal horn via Western blot and immunohistochemistry after nociceptive tests. Here, we found that the analgesic effect of remifentanil was followed by long-term hyperalgesia lasting at least postoperative 7 days, which was accompanied with increase in NR2B expression and trafficking from cytoplasm to surface and MnSOD nitration in dorsal horn. Pretreatment with HRS (10 ml/kg) significantly attenuated mechanical and thermal hyperalgesia, blocked NR2B trafficking and MnSOD nitration in dorsal horn after remifentanil infusion. Ro25-6981 not 5 μg but 10 and 50 μg dosage-dependently attenuated hyperalgesia, and inhibited MnSOD nitration. Hyperalgesia and MnSOD nitration were attenuated after the combination of HRS (2.5 ml/kg) and Ro25-6981 (5 μg). In conclusion, HRS (10 ml/kg) might reverse remifentanil-induced hyperalgesia, through regulating NR2B-containing NMDAR trafficking to control MnSOD nitration and enhance MnSOD activity.

  1. Inhibiting effects of rhynchophylline on zebrafish methamphetamine dependence are associated with amelioration of neurotransmitters content and down-regulation of TH and NR2B expression.

    PubMed

    Jiang, Mingjin; Chen, Yifei; Li, Chan; Peng, Qiuxian; Fang, Miao; Liu, Wei; Kang, Qunzhao; Lin, Yingbo; Yung, Ken Kin Lam; Mo, Zhixian

    2016-07-04

    Others and we have reported that rhynchophylline reverses amphetamine-induced conditioned place preference (CPP) effect which may be partly mediated by amelioration of central neurotransmitters and N-methyl-d-aspartate receptor 2B (NR2B) levels in the rat brains. The current study investigated the inhibiting effects of rhynchophylline on methamphetamine-induced (METH-induced) CPP in adult zebrafish and METH-induced locomotor activity in tyrosine hydroxylase-green fluorescent protein (TH-GFP) transgenic zebrafish larvae and attempted to confirm the hypothesis that these effects were mediated via regulation of neurotransmitters and dopaminergic and glutamatergic systems. After baseline preference test (on days 1-3), zebrafish were injected intraperitoneally METH (on days 4, 6 and 8) or the same volume of fish physiological saline (on days 5 and 7) and were immediately conditioned. Rhynchophylline was administered at 12h after injection of METH. On day 9, zebrafish were tested for METH-induced CPP. Results revealed that rhynchophylline (100mg/kg) significantly inhibited the acquisition of METH-induced CPP, reduced the content of dopamine and glutamate and down-regulated the expression of TH and NR2B in the CPP zebrafish brains. Furthermore, the influence of rhynchophylline on METH-induced locomotor activity was also observed in TH-GFP transgenic zebrafish larvae. Results showed that rhynchophylline (50mg/L) treatment led to a significant reduction on the locomotor activity and TH expression in TH-GFP transgenic zebrafish larvae. Taken together, these data indicate that the inhibition of the formation of METH dependence by rhynchophylline in zebrafish is associated with amelioration of the neurotransmitters dopamine and glutamate content and down-regulation of TH and NR2B expression.

  2. Pharmacological inhibition of PTEN attenuates cognitive deficits caused by neonatal repeated exposures to isoflurane via inhibition of NR2B-mediated tau phosphorylation in rats.

    PubMed

    Tan, Lei; Chen, Xin; Wang, Wei; Zhang, Jianfang; Li, Shiyong; Zhao, Yilin; Wang, Jintao; Luo, Ailin

    2017-03-01

    Evidence has shown that children exposed to repeated anesthesia in early childhood display long-term cognitive disabilities. However, the underlying mechanisms remain largely unclear. Our previous study has indicated the involvement of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in isoflurane-induced decrease of self-renewal capacity in hippocampal neural precursor cells. Additionally, it is demonstrated by others that PTEN inhibition could protect against cognitive impairment via reduction of tau phosphorylation in the alzheimer's disease model. Therefore, in the present in vivo study, we aimed to examine the effects of PTEN inhibition on the cognitive dysfunction and tau hyperphosphorylation caused by neonatal repeated exposures to isoflurane. Our results showed that the neonatal repeated exposures to isoflurane resulted in the activation of PTEN in the hippocampus. The treatment of PTEN inhibitor BPV (pic) restored PSD-95 synthesis, and attenuated tau phosphorylation as well as the cognitive dysfunction caused by the repeated isoflurane exposures. In addition, BPV (pic) treatment reversed the activation of NR2B-containing NMDARs induced by repeated isoflurane exposures, while in turn, the antagonism of NR2B subunit with ifenprodil alleviated tau phosphorylation, indicating a possible role of NR2B as the downstream of PTEN in mediating tau phosphorylation in the neonatal rats repeatedly exposed to isoflurane. In conclusion, our results reveal a novel role of PTEN in mediating tau phosphorylation and cognitive deficits caused by neonatal repeated exposures to isoflurane, implying that targeting on PTEN may be a potential therapeutic approach for the anesthetic-related cognitive decline in the developing brain.

  3. Identification of the N-Methyl-D-aspartate receptor (NMDAR)-related epitope, NR2B, in the normal human ovary: implication for the pathogenesis of anti-NMDAR encephalitis.

    PubMed

    Tachibana, Naoko; Kinoshita, Michiaki; Saito, Yuko; Ikeda, Shu-ichi

    2013-01-01

    N-methyl-D-aspartate receptors (NMDARs) are one type of ionotropic glutamate receptors (GluRs) and are heterotetrametric cation channels composed of NMDAR1 (NR1), NMDAR2 (NR2A, 2B, 2C or 2D) and NMDAR3 (NR3A or NR3B) subunits. The main subunits are NR1 and NR2 and their combinations are classified into several diverse forms including NR1/NR1/NR2A/NR2A, NR1/NR1/NR2B/NR2B and NR1/NR1/NR2A/NR2B. NMDARs are physiologically related to synapse development and synaptic plasticity in the central nervous system. Anti-NMDAR encephalitis is a form of autoimmune limbic encephalitis mainly affecting young women, with various manifestations including initial psychiatric symptoms, subsequent unresponsiveness, intractable generalized seizure, dysautonomia and orofacial dyskinesia. This disorder is often accompanied by ovarian teratoma that is originated from oocytes. Anti-neural antibody for the NR1/NR2 heteromer of NMDAR has been identified as a disease-specific hallmark. It has been emphasized that neural components in ovarian teratoma act as a trigger to produce anti-NMDAR antibodies, although about half of the patients with anti-NMDAR encephalitis are not associated with ovarian teratoma. To identify NMDAR-related epitopes located outside of the brain, we performed immunohistochemical examinations of normal human ovary and testis using specific antibodies against NR1, NR2A and NR2B, respectively, and found expression of the NR2B epitope in the cytoplasm of oocytes. In contrast, the testis showed no immunohistochemical reactivity. Therefore, oocytes contain NMDAR-related epitopes including NR2B. The NMDAR-related epitopes in normal oocytes may cause an antigen-antibody reaction in certain pathological conditions. The presence of NR2B immunoreactivity in oocytes may account for the fact that anti-NMDAR encephalitis predominantly affects young females.

  4. Synthesis, structural activity-relationships, and biological evaluation of novel amide-based allosteric binding site antagonists in NR1A/NR2B N-methyl-D-aspartate receptors☆

    PubMed Central

    Mosley, Cara A.; Myers, Scott J.; Murray, Ernest E.; Santangelo, Rose; Tahirovic, Yesim A.; Kurtkaya, Natalie; Mullasseril, Praseeda; Yuan, Hongjie; Lyuboslavsky, Polina; Le, Phuong; Wilson, Lawrence J.; Yepes, Manuel; Dingledine, Ray; Traynelis, Stephen F.; Liotta, Dennis C.

    2010-01-01

    The synthesis and structure–activity relationship analysis of a novel class of amide-based biaryl NR2B-selective NMDA receptor antagonists are presented. Some of the studied compounds are potent, selective, non-competitive, and voltage-independent antagonists of NR2B-containing NMDA receptors. Like the founding member of this class of antagonists (ifenprodil), several interesting compounds of the series bind to the amino terminal domain of the NR2B subunit to inhibit function. Analogue potency is modu-lated by linker length, flexibility, and hydrogen bonding opportunities. However, unlike previously described classes of NR2B-selective NMDA antagonists that exhibit off-target activity at a variety of monoamine receptors, the compounds described herein show much diminished effects against the hERG channel and α1-adrenergic receptors. Selections of the compounds discussed have acceptable half-lives in vivo and are predicted to permeate the blood–brain barrier. These data together suggest that masking charged atoms on the linker region of NR2B-selective antagonists can decrease undesirable side effects while still maintaining on-target potency. PMID:19648014

  5. Adenosine A₂A receptors permit mGluR5-evoked tyrosine phosphorylation of NR2B (Tyr1472) in rat hippocampus: a possible key mechanism in NMDA receptor modulation.

    PubMed

    Sarantis, Konstantinos; Tsiamaki, Eirini; Kouvaros, Stylianos; Papatheodoropoulos, Costas; Angelatou, Fevronia

    2015-11-01

    A great body of evidence points toward a functional interaction between metabotropic glutamate 5 receptors (mGluR5) and NMDA receptors (NMDAR) that enhances synaptic plasticity and cognition. However, the molecular mechanism underlying this interaction remains unclear. Here, we show that co-activation of mGluR5 and NMDAR in hippocampal slices synergistically leads to a robust phosphorylation of NR2B (Tyr1472), which is Src kinase dependent and is enabled by endogenous adenosine acting on A2A receptors. As it is well known, NR2B (Tyr1472) phosphorylation anchors NR2B-containing NMDARs to the surface of post-synaptic membranes, preventing their internalization. This is supported by our electrophysiological experiments showing that co-activation of mGluR5 and NMDARs robustly enhances NMDAR-dependent neuronal excitability recorded in CA1 hippocampal region, which temporally coincides with the robust increase in NR2B (Tyr1472) phosphorylation, depends on Src kinases and is also permitted by A2A receptors. Thus, we strongly suggest that NR2B (Tyr1472) phosphorylation constitutes, at least to some extent, the molecular mechanism underlying the mGluR5-mediated enhancement of NMDAR-dependent responses, which is modulated by A2A receptors. A better understanding of the molecular basis of mGluR5/NMDAR interaction would elucidate their role in synaptic plasticity processes as well as in pathological conditions. We propose the following molecular mechanism by which metabotropic Glutamate Receptor 5 (mGluR5) potentiate ionotropic Glutamate N-Methyl-D-Aspartate Receptor (NMDAR) responses in rat hippocampus. Co-activation of mGLUR5/NMDAR activates Src kinases, leading to NR2B(Tyr1472) phosphorylation, which anchors NR2B-containing NMDAR to the plasma membrane, thus inducing a robust increase in the NMDA-dependent excitability. Interestingly, adenosine A2A receptors license the mGluR5-induced NR2B(Tyr1472) phosphorylation.

  6. Activation of spinal MrgC-Gi-NR2B-nNOS signaling pathway by Mas oncogene-related gene C receptor agonist bovine adrenal medulla 8-22 attenuates bone cancer pain in mice

    PubMed Central

    Sun, Yu’e; Zhang, Juan; Lei, Yishan; Lu, Cui’e; Hou, Bailing; Ma, Zhengliang; Gu, Xiaoping

    2016-01-01

    Objectives: In the present study, we investigate the effects of Mas oncogene-related gene (Mrg) C receptors (MrgC) on the expression and activation of spinal Gi protein, N-methyl-D-aspartate receptor subunit 2B (NR2B), and neuronal nitric oxide synthase (nNOS) in mouse model of bone cancer pain. Methods: The number of spontaneous foot lift (NSF) and paw withdrawal mechanical threshold (PWMT) were measured after inoculation of tumor cells and intrathecal injection of MrgC agonist bovine adrenal medulla 8-22 (BAM8-22) or MrgC antagonist anti-MrgC for 14 days after operation. Expression of spinal MrgC, Gi protein, NR2B and nNOS and their phosphorylated forms after inoculation was examined by immunohistochemistry and Western blotting. Double labeling was used to identify the co-localization of NR2B or nNOS with MrgC in spinal cord dorsal horn (SCDH) neurons. The effects of intrathecal injection of BAM8-22 or anti-MrgC on nociceptive behaviors and the corresponding expression of spinal MrgC, Gi protein, NR2B and nNOS were also investigated. Results: The expression of spinal MrgC, Gi protein, NR2B, and nNOS was higher in tumor-bearing mice in comparison to sham mice or normal mice. Intrathecal injection of MrgC agonist BAM8-22 significantly alleviated bone cancer pain, up-regulated MrgC and Gi protein expression, and down-regulated the expression of spinal p-NR2B, t-nNOS and p-nNOS in SCDH on day 14 after operation, whereas administration of anti-MrgC produced the opposite effect. Meanwhile, MrgC-like immunoreactivity (IR) co-localizes with NR2B-IR or nNOS-IR in SCDH neurons. Conclusions: The present study demonstrates that MrgC-activated spinal Gi-NR2B-nNOS signaling pathway plays important roles in the development of bone cancer pain. These findings may provide a novel strategy for the treatment of bone cancer pain. PMID:27158400

  7. Amygdala Infusions of an NR2B-Selective or an NR2A-Preferring NMDA Receptor Antagonist Differentially Influence Fear Conditioning and Expression in the Fear-Potentiated Startle Test

    ERIC Educational Resources Information Center

    Walker, David L.; Davis, Michael

    2008-01-01

    Within the amygdala, most N-methyl-D-aspartic acid (NMDA) receptors consist of NR1 subunits in combination with either NR2A or NR2B subunits. Because the particular subunit composition greatly influences the receptors' properties, we investigated the contribution of both subtypes to fear conditioning and expression. To do so, we infused the…

  8. Forelimb dyskinesia mediated by high-frequency stimulation of the subthalamic nucleus is linked to rapid activation of the NR2B subunit of N-methyl-D-aspartate receptors.

    PubMed

    Quintana, Adrien; Melon, Christophe; Kerkerian-Le Goff, Lydia; Salin, Pascal; Savasta, Marc; Sgambato-Faure, Véronique

    2010-08-01

    Dyskinesia is a major side-effect of chronic l-DOPA administration, the reference treatment for Parkinson's disease. High-frequency stimulation of the subthalamic nucleus (STN-HFS) alleviates parkinsonian motor symptoms and indirectly improves dyskinesia by decreasing the L-DOPA requirement. However, inappropriate stimulation can also trigger dyskinetic movements, in both human and rodents. We investigated whether STN-HFS-evoked forelimb dyskinesia involved changes in glutamatergic neurotransmission as previously reported for L-DOPA-induced dyskinesias, focusing on the role of NR2B-containing N-methyl-D-aspartate receptors (NR2B/NMDARs). We applied STN-HFS in normal rats at intensities above and below the threshold for triggering forelimb dyskinesia. Dyskinesiogenic STN-HFS induced the activation of NR2B (as assessed by immunodetection of the phosphorylated residue Tyr(1472)) in neurons of the subthalamic nucleus, entopeduncular nucleus, motor thalamus and forelimb motor cortex. The severity of STN-HFS-induced forelimb dyskinesia was decreased in a dose-dependent manner by systemic injections of CP-101,606, a selective blocker of NR2B/NMDARs, but was either unaffected or increased by the non-selective N-methyl-D-aspartate receptor antagonist, MK-801.

  9. Both NR2A and NR2B Subunits of the NMDA Receptor Are Critical for Long-Term Potentiation and Long-Term Depression in the Lateral Amygdala of Horizontal Slices of Adult Mice

    ERIC Educational Resources Information Center

    Muller, Tobias; Albrecht, Doris; Gebhardt, Christine

    2009-01-01

    The lateral nucleus of the amygdala (LA) is implicated in emotional and social behaviors. We recently showed that in horizontal brain slices, activation of NMDA receptors (NMDARs) is a requirement for persistent synaptic alterations in the LA, such as long-term potentiation (LTP) and long-term depression (LTD). In the LA, NR2A- and NR2B-type NMDRs…

  10. Characterisation of N-methyl-D-aspartate receptor-specific [(3)H]Ifenprodil binding to recombinant human NR1a/NR2B receptors compared with native receptors in rodent brain membranes.

    PubMed

    Grimwood, S; Richards, P; Murray, F; Harrison, N; Wingrove, P B; Hutson, P H

    2000-12-01

    We have performed [(3)H]ifenprodil binding experiments under NMDA receptor-specific assay conditions to provide the first detailed characterisation of the pharmacology of the ifenprodil site on NMDA NR1/NR2B receptors, using recombinant human NR1a/NR2B receptors stably expressed in L(tk-) cells, in comparison with rat cortex/hippocampus membranes. [(3)H]Ifenprodil bound to a single, saturable site on both human recombinant NR1a/NR2B receptors and native rat receptors with B:(max) values of 1.83 and 2.45 pmol/mg of protein, respectively, and K:(D) values of 33.5 and 24.8 nM:, respectively. The affinity of various ifenprodil site ligands-eliprodil, (R:(*), R:(*))-4-hydroxy-alpha-(4-hydroxyphenyl)-beta-methyl-4-pehnyl-1-pi per idineethanol [(+/-)-CP-101,606], cis-3-[4-(4-fluorophenyl)-4-hydroxy-1-piperidinyl]-3, 4-dihydro-2H:-1-benzopyran-4,7-diol [(+/-)-CP-283,097], and (R:(*), S:(*))-alpha-(4-hydroxyphenyl)-beta-methyl-4-(phenylmethyl)-1-piperid inepropanol [(+/-)-Ro 25-6981] was very similar for inhibition of [(3)H]ifenprodil binding to recombinant human NR1a/NR2B and native rat receptors, whereas allosteric inhibition of [(3)H]ifenprodil binding by polyamine site ligands (spermine, spermidine, and arcaine) showed approximately twofold lower affinity for recombinant receptors compared with native receptors. Glutamate site ligands were less effective at modulating [(3)H]ifenprodil binding to recombinant NR1a/NR2B receptors compared with native rat receptors. The NMDA receptor-specific [(3)H]ifenprodil binding conditions described were also applied to ex vivo experiments to determine the receptor occupancy of ifenprodil site ligands [ifenprodil, (+/-)-CP-101,606, (+/-)-CP-283,097, and (+/-)-Ro 25-6981] given systemically.

  11. Different action of a specific NR2B/NMDA antagonist Ro 25-6981 on cortical evoked potentials and epileptic afterdischarges in immature rats.

    PubMed

    Szczurowska, Ewa; Mareš, Pavel

    2015-02-01

    Ro 25-6981 maleate is a highly selective and activity-dependent antagonist of NMDA ionotropic glutamate receptors containing NR2B subunit (NR2B/NMDARs). The aim of our study was to investigate the influence of Ro 25-6981 administration in developing rats on physiological (single and paired pulse cortical interhemispheric evoked potentials) and epileptic brain activity (cortical afterdischarges (ADs)). Electrophysiological experiments were performed in animals with epidurally implanted electrodes at postnatal days (P) P12, P18, and P25. The drug was injected intraperitoneally at a dose of 1 or 3mg/kg. Control animals were injected with saline (1ml/kg). Single interhemispheric responses were evoked with 0.5-ms biphasic pulses with intensities increasing from 0.4 to 5mA, paired-pulse responses were elicited by twofold threshold intensity. The ADs were elicited by series of 15-s of 1-ms pulses at 8-Hz frequency. Firstly, six stimulations with stable suprathreshold intensity repeated at 30-min intervals were used to determine the time course of Ro 25-6981 effects against ADs in P12 animals. Secondly, similar experiment was performed in all age groups of animals but with 20-min intervals as well as a further experiment using stimulations with stepwise intensities increasing at 10-min intervals from 0.2 to 15 mA. Pretreatment with the 3-mg/kg (but not the lower) dose of Ro 25-9681 decreased significantly the amplitude of single responses evoked with higher stimulation intensities in P12 and P18 animals. Both doses affected responses in P25 animals, only the 1-mg/kg dose was more efficacious than the 3-mg/kg one. Paired pulse responses were not affected by either dose of Ro 25-6981 in any age group. Ro 25-9681 clearly influenced the duration of ADs only in P12 animals. The 1-mg/kg dose did not change the duration of ADs whereas the 3-mg/kg dose suppressed progressive prolongation of ADs with repeated stimulations. This effect was seen even 110-min after the drug injection

  12. Intrahippocampal Administration of Ibotenic Acid Induced Cholinergic Dysfunction via NR2A/NR2B Expression: Implications of Resveratrol against Alzheimer Disease Pathophysiology

    PubMed Central

    Karthick, Chennakesavan; Periyasamy, Sabapathy; Jayachandran, Kesavan S.; Anusuyadevi, Muthuswamy

    2016-01-01

    Although several drugs revealed moderate amelioration of symptoms, none of them have sufficient potency to prevent or reverse the progression toward Alzheimer's disease (AD) pathology. Resveratrol (RSV), a polyphenolic compound has shown an outstanding therapeutic effect on a broad spectrum of diseases like age-associated neurodegeneration, inflammation etc. The present study was thus conducted to assess the therapeutic efficacy of RSV in ameliorating the deleterious effects of Ibotenic acid (IBO) in male Wistar rats. Stereotactic intrahippocampal administration of IBO (5 μg/μl) lesioned rats impairs cholinergic transmission, learning and memory performance that is rather related to AD and thus chosen as a suitable model to understand the drug efficacy in preventing AD pathophysiology. Since IBO is an agonist of glutamate, it is expected to exhibit an excitotoxic effect by altering glutamatergic receptors like NMDA receptor. The current study displayed significant alterations in the mRNA expression of NR2A and NR2B subunits of NMDA receptors, and further it is surprising to note that cholinergic receptors decreased in expression particularly α7-nAChR with increased m1AChR. RSV administration (20 mg/kg body weight, i.p.) significantly reduced these changes in IBO induced rats. Glutamatergic and cholinergic receptor alterations were associated with significant changes in the behavioral parameters of rats induced by IBO. While RSV improved spatial learning performance, attenuated immobility, and improvised open field activity in IBO induced rats. NR2B activation in the present study might mediate cell death through oxidative stress that form the basis of abnormal behavioral pattern in IBO induced rats. Interestingly, RSV that could efficiently encounter oxidative stress have significantly decreased stress markers viz., nitrite, PCO, and MDA levels by enhancing antioxidant status. Histopathological analysis displayed significant reduction in the hippocampal

  13. Fragile X mental retardation protein interactions with a G quadruplex structure in the 3'-untranslated region of NR2B mRNA.

    PubMed

    Stefanovic, Snezana; DeMarco, Brett A; Underwood, Ayana; Williams, Kathryn R; Bassell, Gary J; Mihailescu, Mihaela Rita

    2015-12-01

    Fragile X syndrome, the most common cause of inherited intellectual disability, is caused by a trinucleotide CGG expansion in the 5'-untranslated region of the FMR1 gene, which leads to the loss of expression of the fragile X mental retardation protein (FMRP). FMRP, an RNA-binding protein that regulates the translation of specific mRNAs, has been shown to bind a subset of its mRNA targets by recognizing G quadruplex structures. It has been suggested that FMRP controls the local protein synthesis of several protein components of the post synaptic density (PSD) in response to specific cellular needs. We have previously shown that the interactions between FMRP and mRNAs of the PSD scaffold proteins PSD-95 and Shank1 are mediated via stable G-quadruplex structures formed within the 3'-untranslated regions of these mRNAs. In this study we used biophysical methods to show that a comparable G quadruplex structure forms in the 3'-untranslated region of the glutamate receptor subunit NR2B mRNA encoding for a subunit of N-methyl-d-aspartate (NMDA) receptors that is recognized specifically by FMRP, suggesting a common theme for FMRP recognition of its dendritic mRNA targets.

  14. Improving solubility of NR2B amino-terminal domain of N-methyl-D-aspartate receptor expressed in Escherichia coli

    SciTech Connect

    Ng, F.-M.; Soh Wanqin; Geballe, Matthew T.; Low, C.-M.

    2007-10-12

    The amino-terminal domains (ATDs) of N-methyl-D-aspartate (NMDA) receptors contain binding sites for modulators and may serve as potential drug targets in neurological diseases. Here, three fusion tags (6xHis-, GST-, and MBP-) were fused to the ATD of NMDA receptor NR2B subunit (ATD2B) and expressed in Escherichia coli. Each tag's ability to confer enhanced solubility to ATD2B was assessed. Soluble ATD2B was successfully obtained as a MBP fusion protein. Dynamic light scattering revealed the protein (1 mg/ml) exists as monodispersed species at 25 {sup o}C. Functional studies using circular dichroism showed that the soluble MBP-ATD2B bound ifenprodil in a dose-dependent manner. The dissociation constants obtained for ifenprodil were similar in the absence (64 nM) and presence (116 nM) of saturating concentration of maltose. Moreover, the yield of soluble MBP-ATD2B is 18 times higher than the refolded 6xHis-ATD2B. We have reported a systematic comparison of three different affinity tagging strategies and identified a rapid and efficient method to obtain large amount of ATD2B recombinant protein for biochemical and structural studies.

  15. Sigma-1 (σ₁) receptor deficiency reduces β-amyloid(25-35)-induced hippocampal neuronal cell death and cognitive deficits through suppressing phosphorylation of the NMDA receptor NR2B.

    PubMed

    Yin, Jun; Sha, Sha; Chen, Tingting; Wang, Conghui; Hong, Juan; Jie, Pinghui; Zhou, Rong; Li, Lin; Sokabe, Masahiro; Chen, Ling

    2015-02-01

    In early Alzheimer's disease (AD) brain, reduction of sigma-1 receptors (σ1R) is detected. In this study, we employed male heterozygous σ1R knockout (σ1R(+/-)) mice showing normal cognitive performance to investigate association of σ1R deficiency with AD risk. Herein we report that a single injection (i.c.v.) of Aβ(25-35) impaired spatial memory with approximately 25% death of pyramidal cells in the hippocampal CA1 region of WT mice (Aβ(25-35)-WT mice), whereas it did not cause such impairments in σ1R(+/-) mice (Aβ(25-35)-σ1R(+/-) mice). Compared with WT mice, Aβ(25-35)-WT mice showed increased levels of NMDA-activated currents (INMDA) and NR2B phosphorylation (phospho-NR2B) in the hippocampal CA1 region at 48 h after Aβ25-35-injection (post-Aβ(25-35)) followed by approximately 40% decline at 72 h post-Aβ(25-35) of their respective control levels, which was inhibited by the σ1R antagonist NE100. In Aβ(25-35)-WT mice, the administration of NR2B inhibitor Ro25-6981 or NE100 on day 1-4 post-Aβ(25-35) attenuated the memory deficits and loss of pyramidal cells. By contrast, Aβ(25-35)-σ1R(+/-) mice showed a slight increase in the INMDA density and the phospho-NR2B at 48 h or 72 h post-Aβ25-35 compared to σ1R(+/-) mice. Treatment with σ1R agonist PRE084 in Aβ(25-35)-σ1R(+/-) mice caused the same changes in the INMDA density and the phospho-NR2B as those in Aβ(25-35)-WT mice. Furthermore, Aβ(25-35)-σ1R(+/-) mice treated with the NMDA receptor agonist NMDA or PRE084 on day 1-4 post-Aβ(25-35) showed a loss of neuronal cells and memory impairment. These results indicate that the σ1R deficiency can reduce Aβ(25-35)-induced neuronal cell death and cognitive deficits through suppressing Aβ(25-35)-enhanced NR2B phosphorylation.

  16. Inhibition of N-methyl-D-aspartate-activated current by bis(7)-tacrine in HEK-293 cells expressing NR1/NR2A or NR1/NR2B receptors.

    PubMed

    Liu, Yuwei; Li, Chaoying

    2012-12-01

    In normal rat forebrain, the NR1/NR2A and NR1/NR2B dimmers are the main constitutional forms of NMDA receptors. The present study was carried out to determine the functional properties of the heteromeric NMDA receptor subunits and their inhibition by bis(7)-tacrine (B7T). Rat NR1, NR2A and NR2B cDNAs were transfected into human embryonic kidney 293 cells (HEK-293). The inhibition of NMDA-activated currents by B7T was detected in HEK-293 cell expressing NR1/NR2A or NR1/NR2B receptors by using whole-cell patch-clamp techniques. The results showed that in HEK-293 cells expressing NR1/NR2A receptor, 1 μmol/L B7T inhibited 30 μmol/L NMDA- and 1000 μmol/L NMDA-activated steady-state currents by 46% and 40%, respectively (P>0.05; n=5), suggesting that the inhibition of B7T on NR1/NR2A receptor doesn't depend on NMDA concentration, which is consistent with a non-competitive mechanism of inhibition. But for the NR1/NR2B receptor, 1 μmol/L B7T inhibited 30 μmol/L NMDA- and 1000 μmol/L NMDA-activated steady-state currents by 61% and 13%, respectively (P<0.05; n=6), showing that B7T appears to be competitive with NMDA. In addition, simultaneous application of 1 μmol/L B7T and 1000 μmol/L NMDA produced a moderate inhibition of peak NMDA-activated current, followed by a gradual decline of the current to a steady state. However, the gradual onset of inhibition produced by B7T applied simultaneously with NMDA was eliminated when B7T was given 5 s before NMDA. These results suggested that B7T inhibition of NMDA current mediated by NR1/NR2B receptor was slow onset, and it did not depend on the presence of the agonist. With holding potentials ranging from -50 to +50 mV, the B7T inhibition rate of NMDA currents didn't change significantly, and neither did the reversal potential. We are led to conclude that the NR1/NR2B recombinant receptor can serve as a very useful model for studying the molecular mechanism of NMDA receptor inhibition by B7T.

  17. Identification and characterization of 4-methylbenzyl 4-[(pyrimidin-2-ylamino)methyl]piperidine-1-carboxylate, an orally bioavailable, brain penetrant NR2B selective N-methyl-D-aspartate receptor antagonist.

    PubMed

    Liverton, Nigel J; Bednar, Rodney A; Bednar, Bohumil; Butcher, John W; Claiborne, Christopher F; Claremon, David A; Cunningham, Michael; DiLella, Anthony G; Gaul, Stanley L; Libby, Brian E; Lyle, Elizabeth A; Lynch, Joseph J; McCauley, John A; Mosser, Scott D; Nguyen, Kevin T; Stump, Gary L; Sun, Hong; Wang, Hao; Yergey, James; Koblan, Kenneth S

    2007-02-22

    The discovery of a novel series of NR2B subtype selective N-methyl-d-aspartate (NMDA) antagonists is reported. Initial optimization of a high-throughput screening lead afforded an aminopyridine derivative 13 with significant NR2B antagonist potency but limited selectivity over hERG-channel and other off-target activities. Further structure-activity studies on the aminoheterocycle moiety and optimization of the carbamate led to the highly potent 2-aminopyrimidine derivative 20j with a significantly improved off-target activity profile and oral bioavailability in multiple species coupled with good brain penetration. Compound 20j demonstrated efficacy in in vivo rodent models of antinociception, allodynia, and Parkinson's disease.

  18. Analgesic Effect of Intrathecal Administration of Chemokine Receptor CCR2 Antagonist is Related to Change in Spinal NR2B, nNOS, and SIGIRR Expression in Rat with Bone Cancer Pain.

    PubMed

    Ren, Fei; Jiao, Hena; Cai, Hongwei

    2015-06-01

    The purpose of this study is to investigate the analgesic effect of intrathecal injection of chemokine receptor CCR2 antagonist RS102895, and its effect on spinal expression of N-methyl-D-aspartate (NMDA) receptor NR2B subunit, neuronal nitric oxide synthase (nNOS), and SIGIRR in a rat model of bone cancer pain (BCP). A rat model of BCP was established by intro-tibial inoculation of W256 breast cancer cells. Female SD rats were randomly divided into five groups (n = 10 each): Sham group, Sham + RS102895 group, BCP group, BCP + RS102895 group, and BCP + DMSO group. Rats received intrathecal injections of either RS102895 (3 g/l) 10 μl or 10 % DMSO 10 μl on day 9 to day 20 after operation. Pain thresholds of mechanical stimulation and thermal stimulation of each group were measured one day before and at 3rd, 6th, 9th, 12th, 15th, and 20th days after surgery. Spinal expression of NR2B, nNOS, and SIGIRR was detected by RT-PCR and Western blot. CCR2 antagonist RS102895 can suppress the pain induced by both mechanical and thermal stimulation in rats with BCP. Spinal expression of CCR2, NR2B, and nNOS was significantly up-regulated, while SIGIRR was down-regulated in BCP rats, and intrathecal injection of RS102895 effectively reversed the pattern of NR2B, nNOS, and SIGIRR expression in spinal cord. Analgesic effects of CCR2 antagonist RS102895 in BCP rats may be related to its downregulation of signal transduction pathway of NMDAR/nNOS and upregulation of Toll-interleukin-1 receptor member SIGIRR.

  19. Dopamine receptor D5 deficiency results in a selective reduction of hippocampal NMDA receptor subunit NR2B expression and impaired memory.

    PubMed

    Moraga-Amaro, Rodrigo; González, Hugo; Ugalde, Valentina; Donoso-Ramos, Juan Pablo; Quintana-Donoso, Daisy; Lara, Marcelo; Morales, Bernardo; Rojas, Patricio; Pacheco, Rodrigo; Stehberg, Jimmy

    2016-04-01

    Pharmacological evidence associates type I dopamine receptors, including subtypes D1 and D5, with learning and memory. Analyses using genetic approaches have determined the relative contribution of dopamine receptor D1 (D1R) in cognitive tasks. However, the lack of drugs that can discriminate between D1R and D5R has made the pharmacological distinction between the two receptors difficult. Here, we aimed to determine the role of D5R in learning and memory. In this study we tested D5R knockout mice and wild-type littermates in a battery of behavioral tests, including memory, attention, locomotion, anxiety and motivational evaluations. Our results show that genetic deficiency of D5R significantly impairs performance in the Morris water maze paradigm, object location and object recognition memory, indicating a relevant role for D5R in spatial memory and recognition memory. Moreover, the lack of D5R resulted in decreased exploration and locomotion. In contrast, D5R deficiency had no impact on working memory, anxiety and depressive-like behavior, measured using the spontaneous alternation, open-field, tail suspension test, and forced swimming test. Electrophysiological analyses performed on hippocampal slices showed impairment in long-term-potentiation in mice lacking D5R. Further analyses at the molecular level showed that genetic deficiency of D5R results in a strong and selective reduction in the expression of the NMDA receptor subunit NR2B in the hippocampus. These findings demonstrate the relevant contribution of D5R in memory and suggest a functional interaction of D5R with hippocampal glutamatergic pathways.

  20. Differential modulation of Ca2+/calmodulin-dependent protein kinase II activity by regulated interactions with N-methyl-D-aspartate receptor NR2B subunits and alpha-actinin.

    PubMed

    Robison, A J; Bartlett, Ryan K; Bass, Martha A; Colbran, Roger J

    2005-11-25

    Neuronal Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) interacts with several prominent dendritic spine proteins, which have been termed CaMKII-associated proteins. The NR2B subunit of N-methyl-d-aspartate (NMDA)-type glutamate receptor, densin-180, and alpha-actinin bind comparable, approximately stoichiometric amounts of Thr(286)-autophosphorylated CaMKIIalpha, forming a ternary complex (Robison, A. J., Bass, M. A., Jiao, Y., Macmillan, L. B., Carmody, L. C., Bartlett, R. K., and Colbran, R. J. (2005) J. Biol. Chem. 280, 35329-35336), but their impacts on CaMKII function are poorly understood. Here we show that these interactions are differentially regulated and exert distinct effects on CaMKII activity. Nonphosphorylated and Thr(286)-autophosphorylated CaMKII bind to alpha-actinin with similar efficacy, but autophosphorylation at Thr(305/306) or Ca(2+)/calmodulin binding significantly reduce this binding. Moreover, alpha-actinin antagonizes CaMKII activation by Ca(2+)/calmodulin, as assessed by autophosphorylation and phosphorylation of a peptide substrate. CaMKII binding to densin (1247-1542) is partially independent of Thr(286) autophosphorylation and is unaffected by Ca(2+)-independent autophosphorylation or Ca(2+)/calmodulin. In addition, the CaMKII binding domain of densin-180 has little effect on CaMKII activity. In contrast, the interaction of CaMKIIalpha with NR2B requires either Thr(286) autophosphorylation or the binding of both Ca(2+)/calmodulin and adenine nucleotides. NR2B inhibits both the Ca(2+)/calmodulin-dependent and autonomous activities of CaMKII by a mechanism that is competitive with autocamtide-2 substrate, non-competitive with syntide-2 substrate, and uncompetitive with respect to ATP. In combination, these data suggest that dynamically regulated interactions with CaMKII-associated proteins could play pleiotropic roles in finetuning CaMKII signaling in defined subcellular compartments.

  1. NR2B subunit-dependent long-term potentiation enhancement in the rat cortical auditory system in vivo following masking of patterned auditory input by white noise exposure during early postnatal life.

    PubMed

    Hogsden, Jennifer L; Dringenberg, Hans C

    2009-08-01

    The composition of N-methyl-D-aspartate (NMDA) receptor subunits influences the degree of synaptic plasticity expressed during development and into adulthood. Here, we show that theta-burst stimulation of the medial geniculate nucleus reliably induced NMDA receptor-dependent long-term potentiation (LTP) of field postsynaptic potentials recorded in the primary auditory cortex (A1) of urethane-anesthetized rats. Furthermore, substantially greater levels of LTP were elicited in juvenile animals (30-37 days old; approximately 55% maximal potentiation) than in adult animals (approximately 30% potentiation). Masking patterned sound via continuous white noise exposure during early postnatal life (from postnatal day 5 to postnatal day 50-60) resulted in enhanced, juvenile-like levels of LTP (approximately 70% maximal potentiation) relative to age-matched controls reared in unaltered acoustic environments (approximately 30%). Rats reared in white noise and then placed in unaltered acoustic environments for 40-50 days showed levels of LTP comparable to those of adult controls, indicating that white noise rearing results in a form of developmental arrest that can be overcome by subsequent patterned sound exposure. We explored the mechanisms mediating white noise-induced plasticity enhancements by local NR2B subunit antagonist application in A1. NR2B subunit antagonists (Ro 25-6981 or ifenprodil) completely reversed white noise-induced LTP enhancement at concentrations that did not affect LTP in adult or age-matched controls. We conclude that white noise exposure during early postnatal life results in the maintenance of juvenile-like, higher levels of plasticity in A1, an effect that appears to be critically dependent on NR2B subunit activation.

  2. Synthesis and in vitro characterization of trans- and cis-[(18)F]-4-methylbenzyl 4-[(pyrimidin-2-ylamino)methyl]-3-fluoropiperidine-1-carboxylates as new potential PET radiotracer candidates for the NR2B subtype N-methyl-D-aspartate receptor.

    PubMed

    Koudih, Radouane; Gilbert, Gwénaëlle; Dhilly, Martine; Abbas, Ahmed; Barré, Louisa; Debruyne, Danièle; Sobrio, Franck

    2012-07-01

    Diastereoisomeric compounds [(18)F]cis- and [(18)F]trans-4-methylbenzyl 4-[(pyrimidin-2-ylamino)methyl]-3-fluoro-piperidine-1-carboxylates were successfully synthesized as new subtype-selective PET radiotracers for imaging the NR2B subunit containing NMDA receptors. Rat brain section autoradiographies demonstrated a high specific binding in NR2B/NMDA receptor rich regions for both radioligands. The measured logD(7.4) values as well as B(max)/K(d) ratios indicated that both radiotracers possess the adequate properties required for PET radiotracers.

  3. Effects of prenatal chronic mild stress exposure on hippocampal cell proliferation, expression of GSK-3α, β and NR2B in adult offspring during fear extinction in rats.

    PubMed

    Li, Min; Li, Xiaobai; Zhang, Xinxin; Ren, Jintao; Jiang, Han; Wang, Yan; Ma, Yuchao; Cheng, Wenwen

    2014-06-01

    Stress during pregnancy has been implicated as a risk factor for the development of many mental disorders; however, the influence of prenatal stress on the fear or anxiety-related behaviors, especially the fear extinction in adult offspring has been little investigated. In order to investigate how prenatal stress affects fear extinction, which is regarded as a form of new learning that counteracts the expression of Pavlovian's conditioned fear, a rat model of prenatal chronic mild stress (PNS) was used to evaluate the effects of PNS on fear extinction in adult offspring. The expression of hippocampal glycogen synthase kinase-3s (GSK-3α, β), N-methyl-d-aspartic acid receptors (NMDARs)-2B and the hippocampal cell proliferation in dentate gyrus in the adult offspring during fear extinction were studied. Our results showed that PNS significantly reduced body weight of pups, indicating PNS might induce growth retardation in offspring. Moreover, PNS significantly enhanced the freezing behavior of offspring at the phase of extinction, suggesting PNS impaired the abilities of fear extinction learning. In addition, PNS significantly increased the levels of GSK-3α, β and NR2B, but reduced hippocampal cell proliferation during fear extinction. Taken together, our findings suggest that maternal stress during pregnancy can impair the fear extinction of adult offspring, probably by affecting the neural plasticity of brain.

  4. Traxoprodil, a selective antagonist of the NR2B subunit of the NMDA receptor, potentiates the antidepressant-like effects of certain antidepressant drugs in the forced swim test in mice.

    PubMed

    Poleszak, Ewa; Stasiuk, Weronika; Szopa, Aleksandra; Wyska, Elżbieta; Serefko, Anna; Oniszczuk, Anna; Wośko, Sylwia; Świąder, Katarzyna; Wlaź, Piotr

    2016-08-01

    One of the newest substances, whose antidepressant activity was shown is traxoprodil, which is a selective antagonist of the NR2B subunit of the NMDA receptor. The main goal of the present study was to evaluate the effect of traxoprodil on animals' behavior using the forced swim test (FST), as well as the effect of traxoprodil (10 mg/kg) on the activity of antidepressants, such as imipramine (15 mg/kg), fluoxetine (5 mg/kg), escitalopram (2 mg/kg) and reboxetine (2.5 mg/kg). Serotonergic lesion and experiment using the selective agonists of serotonin receptors 5-HT1A and 5-HT2 was conducted to evaluate the role of the serotonergic system in the antidepressant action of traxoprodil. Brain concentrations of tested agents were determined using HPLC. The results showed that traxoprodil at a dose of 20 and 40 mg/kg exhibited antidepressant activity in the FST and it was not related to changes in animals' locomotor activity. Co-administration of traxoprodil with imipramine, fluoxetine or escitalopram, each in subtherapeutic doses, significantly affected the animals' behavior in the FST and, what is important, these changes were not due to the severity of locomotor activity. The observed effect of traxoprodil is only partially associated with serotonergic system and is independent of the effect on the 5-HT1A and 5-HT2 serotonin receptors. The results of an attempt to assess the nature of the interaction between traxoprodil and the tested drugs show that in the case of joint administration of traxoprodil and fluoxetine, imipramine or escitalopram, there were interactions in the pharmacokinetic phase.

  5. La pelade par plaques

    PubMed Central

    Spano, Frank; Donovan, Jeff C.

    2015-01-01

    Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre l’épidémiologie, la pathogenèse, l’histologie et l’approche clinique au diagnostic de la pelade par plaques. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant la pathogenèse, le diagnostic et le pronostic de la pelade par plaques. Message principal La pelade par plaques est une forme de perte pileuse auto-immune dont la prévalence durant une vie est d’environ 2 %. Des antécédents personnels ou familiaux de troubles auto-immuns concomitants, comme le vitiligo ou une maladie de la thyroïde, peuvent être observés dans un petit sous-groupe de patients. Le diagnostic peut souvent être posé de manière clinique en se fondant sur la perte de cheveux non cicatricielle et circulaire caractéristique, accompagnée de cheveux en « point d’exclamation » en périphérie chez ceux dont le problème en est aux premiers stades. Le diagnostic des cas plus complexes ou des présentations inhabituelles peut être facilité par une biopsie et un examen histologique. Le pronostic varie largement et de mauvais résultats sont associés à une apparition à un âge précoce, une perte importante, la variante ophiasis, des changements aux ongles, des antécédents familiaux ou des troubles auto-immuns concomitants. Conclusion La pelade par plaques est une forme auto-immune de perte de cheveux périodiquement observée en soins primaires. Les médecins de famille sont bien placés pour identifier la pelade par plaques, déterminer la gravité de la maladie et poser le diagnostic différentiel approprié. De plus, ils sont en mesure de renseigner leurs patients à propos de l’évolution clinique de la maladie ainsi que du pronostic général selon le sous-type de patients.

  6. La pelade par plaques

    PubMed Central

    Spano, Frank; Donovan, Jeff C.

    2015-01-01

    Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre les schémas thérapeutiques et les résultats des traitements pour la pelade par plaques, de même que les aider à identifier les patients pour qui une demande de consultation en dermatologie pourrait s’imposer. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant le traitement de la pelade par plaques. Message principal La pelade par plaques est une forme auto-immune de perte pileuse qui touche à la fois les enfants et les adultes. Même s’il n’y a pas de mortalité associée à la maladie, la morbidité découlant des effets psychologiques de la perte des cheveux peut être dévastatrice. Lorsque la pelade par plaques et le sous-type de la maladie sont identifiés, un schéma thérapeutique approprié peut être amorcé pour aider à arrêter la chute des cheveux et possiblement faire commencer la repousse. Les traitements de première intention sont la triamcinolone intralésionnelle avec des corticostéroïdes topiques ou du minoxidil ou les 2. Les médecins de famille peuvent prescrire ces traitements en toute sécurité et amorcer ces thérapies. Les cas plus avancés ou réfractaires pourraient avoir besoin de diphénylcyclopropénone topique ou d’anthraline topique. On peut traiter la perte de cils avec des analogues de la prostaglandine. Les personnes ayant subi une perte de cheveux abondante peuvent recourir à des options de camouflage ou à des prothèses capillaires. Il est important de surveiller les troubles psychiatriques en raison des effets psychologiques profonds de la perte de cheveux. Conclusion Les médecins de famille verront de nombreux patients qui perdent leurs cheveux. La reconnaissance de la pelade par plaques et la compréhension du processus pathologique sous-jacent permettent d’amorcer un schéma thérapeutique approprié. Les cas plus graves ou r

  7. (3R,4S)-3-[4-(4-fluorophenyl)-4-hydroxypiperidin-1-yl]chroman-4,7-diol: a conformationally restricted analogue of the NR2B subtype-selective NMDA antagonist (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidino)- 1-propanol.

    PubMed

    Butler, T W; Blake, J F; Bordner, J; Butler, P; Chenard, B L; Collins, M A; DeCosta, D; Ducat, M J; Eisenhard, M E; Menniti, F S; Pagnozzi, M J; Sands, S B; Segelstein, B E; Volberg, W; White, W F; Zhao, D

    1998-03-26

    (1S,2S)-1-(4-Hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidino)-1-propanol (CP-101,606, 1) is a recently described antagonist of N-methyl-D-aspartate (NMDA) receptors containing the NR2B subunit. In the present study, the optimal orientation of compounds of this structural type for their receptor was explored. Tethering of the pendent methyl group of 1 to the phenolic aromatic ring via an oxygen atom prevents rotation about the central portion of the molecule. Several of the new chromanol compounds have high affinity for the racemic [3H]CP-101,606 binding site on the NMDA receptor and protect against glutamate toxicity in cultured hippocampal neurons. The new ring caused a change in the stereochemical preference of the receptor-cis (erythro) compounds had better affinity for the receptor than the trans isomers. Computational studies suggest that steric interactions between the pendent methyl group and the phenol ring in the acyclic series determine which structures can best fit the receptor. The chromanol analogue, (3R,4S)-3-[4-(4-fluorophenyl)-4-hydroxypiperidin-1- yl]chroman-4,7-diol (12a, CP-283,097), was found to possess potency and selectivity comparable to CP-101,606. Thus 12a is a new tool to explore the function of the NR2B-containing NMDA receptors.

  8. THE MEASURES PAR PROJECT

    NASA Astrophysics Data System (ADS)

    Frouin, R. J.; Franz, B.

    2009-12-01

    The solar energy available for photosynthesis, known as PAR, controls the growth of phytoplankton and, therefore, regulates the composition and evolution of marine ecosystems. Knowing the spatial and temporal distribution of PAR over the oceans is critical to understanding biogeochemical cycles of carbon, nutrients, and oxygen, and to address important climate and global change issues such as the fate of anthropogenic atmospheric carbon dioxide. In view of this, a 12-year time series of PAR at the ocean surface, starting in September 1997, is being produced by the NASA Ocean Biology Processing Group from SeaWiFS, MODIS-Terra, and MODIS-Aqua data. The product covers the global oceans, with a spatial resolution of about 9.3x9.3 km (equal area grid) and a temporal resolution of one day. PAR is computed as the difference between the 400-700 nm solar flux incident on the top of the atmosphere (known) and reflected back to space by the atmosphere and surface (derived from satellite radiance), taking into account atmospheric absorption (modeled). Knowledge of pixel composition is not required, eliminating the need for cloud screening and arbitrary assumptions about sub-pixel cloudiness. Combining data from satellite sensors with different equatorial crossing times accounts for the diurnal variability of clouds and, therefore, increases accuracy on a daily time scale. The processing system, including routine check of accuracy and control of quality, is designed to operate during the entire lifetime of SeaWiFS and MODIS, and to accommodate future sensors with ocean-color capabilities. Maps of daily, weekly, and monthly PAR obtained from individual sensors are presented, as well as merged products. Accuracy is quantified in comparisons with other satellite estimates, the National Centers for Environmental Prediction reanalysis product, and in-situ measurements from fixed buoys and platforms. The good statistical performance makes the satellite PAR product suitable for large

  9. Brulures par Diluant

    PubMed Central

    Benbrahim, A.; Jerrah, H.; Diouri, M.; Bahechar, N.; Boukind, E.H.

    2009-01-01

    Summary La flamme de diluant est une cause non rare de brûlure dans le contexte marocain. Nous avons jugé intéressant de faire une étude épidémiologique sur la brûlure par flamme de diluant (BFD) au centre national des brûlés (CNB) du CHU Ibn-Rochd de Casablanca. Ce travail a été réalisé sur une période de 10 mois (septembre 2007/juin 2008). Le but du travail est de montrer les caractéristiques de ce type de brûlures pour les prévenir et ce par l'information sur le diluant, produit causant ces brûlures, et ses différents dangers, la brûlure notamment. Durant cette période, nous avons colligé 17 cas de BFD sur un total de 356 patients admis au CNB pour brûlures aiguës toute étiologie confondue. La moyenne d'age des patients concernés est de 32 ans. Ils sont presque tous de sexe masculin (16 hommes/1 femme) et ont des antécédents de toxicomanie et/ou de délinquance. Tous nos patients sont de bas niveau socio-économique et habitent dans des bidonvilles pour la plupart. La brûlure est souvent secondaire à une agression dans la rue (92% des cas). Concernant les caractéristiques de la brûlure, la surface cutanée brûlée moyenne est de 23%; elle est souvent profonde et siège surtout au niveau des membres supérieurs et du tronc. PMID:21991179

  10. Par Pond vegetation status 1996

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-12-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned.

  11. Exploration of locomotion in the ParA/ParB system

    NASA Astrophysics Data System (ADS)

    Jindal, Lavisha; Emberly, Eldon

    2015-03-01

    In many bacteria the ParA/ParB system is responsible for actively segregating DNA during replication. ParB precessively moves by hydrolyzing DNA bound ParA-ATP forming a depleted ParA region in its wake. Recent in-vitro experiments have shown that a ParB covered bead can traverse a ParA bound DNA substrate. It has been suggested that the formation of a gradient in ParA leads to diffusion-ratchet like motion of the ParB bead but its origin and potential consequences requires investigation. We have developed a deterministic model for the in-vitro ParA/ParB system and show that any amount of spatial noise in ParA can lead to the spontaneous formation of its gradient. The velocity of the bead is independent of this noise but depends on the scale over which ParA exerts a force on the bead and the scale over which ParB hydrolyzes ParA from the substrate. There is a particular ratio of these scales at which the velocity is a maximum. We also explore the effects of cooperative vs independent rebinding of ParA to the substrate. Our model shows how the driving force for ParB originates and highlights necessary conditions for directed motion in the in-vitro system that may provide insight into the in-vivo behaviour of the ParA/ParB system.

  12. Par Pond Fish, Water, and Sediment Chemistry

    SciTech Connect

    Paller, M.H.; Wike, L.D.

    1996-06-01

    The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

  13. Directed and persistent movement arises from mechanochemistry of the ParA/ParB system

    NASA Astrophysics Data System (ADS)

    Hu, Longhua; Vecchiarelli, Anthony G.; Mizuuchi, Kiyoshi; Neuman, Keir C.; Liu, Jian

    The segregation of DNA prior to cell division is essential for faithful genetic inheritance. In many bacteria, segregation of the low-copy-number plasmids involves an active partition system composed of ParA ATPase and its stimulator protein ParB. Recent experiments suggest that ParA/ParB system motility is driven by a diffusion-ratchet mechanism in which ParB-coated plasmid both creates and follows a ParA gradient on the nucleoid surface. However, the detailed mechanism of ParA/ParB-mediated directed and persistent movement remains unknown. We develop a theoretical model describing ParA/ParB-mediated motility. We show that the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent cycling of ParA-nucleoid affinity to the motion of the ParB bound cargo. Paradoxically, the resulting processive motion relies on quenching diffusive plasmid motion through a large number of transient ParA/ParB-mediated tethers to the nucleoid surface. Our work sheds light on a new emergent phenomenon in which non-motor proteins work collectively via mechanochemical coupling to propel cargos -- an ingenious solution shaped by evolution to cope with the lack of processive motor proteins in bacteria.

  14. suPAR: The Molecular Crystal Ball

    PubMed Central

    Thunø, Maria; Macho, Betina; Eugen-Olsen, Jesper

    2009-01-01

    soluble urokinase Plasminogen Activator Receptor (suPAR) levels reflect inflammation and elevated suPAR levels are found in several infectious diseases and cancer. suPAR exists in three forms; suPARI-III, suPARII-III and suPARI which show different properties due to structural differences. Studies suggest that full-length suPAR is a regulator of uPAR/uPA by acting as uPA-scavenger, whereas the cleaved suPARII-III act as a chemotactic agent promoting the immune response via the SRSRY sequence in the linker-region. This review focus on the various suPAR fragments and their involvement in inflammation and pathogenic processes. We focus on the molecular mechanisms of the suPAR fragments and the link to the inflammatory process, as this could lead to medical applications in infectious and pathological conditions. PMID:19893210

  15. PAR for the Course: A Congruent Pedagogical Approach for a PAR Methods Class

    ERIC Educational Resources Information Center

    Hammond, Joyce D.; Hicks, Maria; Kalman, Rowenn; Miller, Jason

    2005-01-01

    In the past two years, three graduate students and a senior faculty member have co-taught a participatory action research (PAR) course to undergraduate and graduate students. In this article the co-teachers advocate a set of pedagogical principles and practices in a PAR-oriented classroom that establishes congruency with community PAR projects in…

  16. Par Pond vegetation status Summer 1995 -- Summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1996-01-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

  17. Comparative cactus architecture and par interception

    SciTech Connect

    Geller, G.N.; Nobel, P.S. )

    1987-07-01

    Because CO{sup 2} uptake by cacti can be limited by low levels of photosynthetically active radiation (PAR) and because plant form affects PAR interception, various cactus forms were studied using a computer model, field measurements, and laboratory phototropic studies. Model predictions indicated that CO{sub 2} uptake by individual stems at an equinox was greatest when the stem were vertical, but at the summer and the winter solstice CO{sub 2} uptake was greatest for stems titled 30{degree} away from the equator. Stem tilting depended on form and taxonomic group. Not only can the shape of cacti be affected by PAR, but also shape influences PAR interception and hence CO{sub 2} uptake.

  18. Techniques for measuring intercepted and absorbed PAR in corn canopies

    NASA Technical Reports Server (NTRS)

    Gallo, K. P.; Daughtry, C. S. T.

    1984-01-01

    The quantity of radiation potentially available for photosynthesis that is captured by the crop is best described as absorbed photosynthetically active radiation (PAR). Absorbed PAR (APAR) is the difference between descending and ascending fluxes. The four components of APAR were measured above and within two planting densities of corn (Zea mays L.) and several methods of measuring and estimating APAR were examined. A line quantum sensor that spatially averages the photosynthetic photon flux density provided a rapid and portable method of measuring APAR. PAR reflectance from the soil (Typic Argiaquoll) surface decreased from 10% to less than 1% of the incoming PAR as the canopy cover increased. PAR reflectance from the canopy decreased to less than 3% at maximum vegetative cover. Intercepted PAR (1 - transmitted PAR) generally overestimated absorbed PAR by less than 4% throughout most of the growing season. Thus intercepted PAR appears to be a reasonable estimate of absorbed PAR.

  19. Protease-activated receptor (PAR) 1 and PAR4 differentially regulate factor V expression from human platelets.

    PubMed

    Duvernay, Matthew; Young, Summer; Gailani, David; Schoenecker, Jonathan; Hamm, Heidi E; Hamm, Heidi

    2013-04-01

    With the recent interest of protease-activated receptors (PAR) 1 and PAR4 as possible targets for the treatment of thrombotic disorders, we compared the efficacy of protease-activated receptor (PAR)1 and PAR4 in the generation of procoagulant phenotypes on platelet membranes. PAR4-activating peptide (AP)-stimulated platelets promoted thrombin generation in plasma up to 5 minutes earlier than PAR1-AP-stimulated platelets. PAR4-AP-mediated factor V (FV) association with the platelet surface was 1.6-fold greater than for PAR1-AP. Moreover, PAR4 stimulation resulted in a 3-fold greater release of microparticles, compared with PAR1 stimulation. More robust FV secretion and microparticle generation with PAR4-AP was attributable to stronger and more sustained phosphorylation of myosin light chain at serine 19 and threonine 18. Inhibition of Rho-kinase reduced PAR4-AP-mediated FV secretion and microparticle generation to PAR1-AP-mediated levels. Thrombin generation assays measuring prothrombinase complex activity demonstrated 1.5-fold higher peak thrombin levels on PAR4-AP-stimulated platelets, compared with PAR1-AP-stimulated platelets. Rho-kinase inhibition reduced PAR4-AP-mediated peak thrombin generation by 25% but had no significant effect on PAR1-AP-mediated thrombin generation. In conclusion, stimulation of PAR4 on platelets leads to faster and more robust thrombin generation, compared with PAR1 stimulation. The greater procoagulant potential is related to more efficient FV release from intracellular stores and microparticle production driven by stronger and more sustained myosin light chain phosphorylation. These data have implications about the role of PAR4 during hemostasis and are clinically relevant in light of recent efforts to develop PAR antagonists to treat thrombotic disorders.

  20. PAR2 regulates regeneration, transdifferentiation, and death

    PubMed Central

    Piran, Ron; Lee, Seung-Hee; Kuss, Pia; Hao, Ergeng; Newlin, Robbin; Millán, José Luis; Levine, Fred

    2016-01-01

    Understanding the mechanisms by which cells sense and respond to injury is central to developing therapies to enhance tissue regeneration. Previously, we showed that pancreatic injury consisting of acinar cell damage+β-cell ablation led to islet cell transdifferentiation. Here, we report that the molecular mechanism for this requires activating protease-activated receptor-2 (PAR2), a G-protein-coupled receptor. PAR2 modulation was sufficient to induce islet cell transdifferentiation in the absence of β-cells. Its expression was modulated in an islet cell type-specific manner in murine and human type 1 diabetes (T1D). In addition to transdifferentiation, PAR2 regulated β-cell apoptosis in pancreatitis. PAR2's role in regeneration is broad, as mice lacking PAR2 had marked phenotypes in response to injury in the liver and in digit regeneration following amputation. These studies provide a pharmacologically relevant target to induce tissue regeneration in a number of diseases, including T1D. PMID:27809303

  1. ATP-regulated interactions between P1 ParA, ParB and non-specific DNA that are stabilized by the plasmid partition site, parS

    PubMed Central

    Havey, James C.; Vecchiarelli, Anthony G.; Funnell, Barbara E.

    2012-01-01

    Localization of the P1 plasmid requires two proteins, ParA and ParB, which act on the plasmid partition site, parS. ParB is a site-specific DNA-binding protein and ParA is a Walker-type ATPase with non-specific DNA-binding activity. In vivo ParA binds the bacterial nucleoid and forms dynamic patterns that are governed by the ParB–parS partition complex on the plasmid. How these interactions drive plasmid movement and localization is not well understood. Here we have identified a large protein–DNA complex in vitro that requires ParA, ParB and ATP, and have characterized its assembly by sucrose gradient sedimentation and light scattering assays. ATP binding and hydrolysis mediated the assembly and disassembly of this complex, while ADP antagonized complex formation. The complex was not dependent on, but was stabilized by, parS. The properties indicate that ParA and ParB are binding and bridging multiple DNA molecules to create a large meshwork of protein–DNA molecules that involves both specific and non-specific DNA. We propose that this complex represents a dynamic adaptor complex between the plasmid and nucleoid, and further, that this interaction drives the redistribution of partition proteins and the plasmid over the nucleoid during partition. PMID:21965538

  2. Humanizing the Protease-Activated Receptor (PAR) Expression Profile in Mouse Platelets by Knocking PAR1 into the Par3 Locus Reveals PAR1 Expression Is Not Tolerated in Mouse Platelets

    PubMed Central

    French, Shauna L.; Paramitha, Antonia C.; Moon, Mitchell J.; Dickins, Ross A.; Hamilton, Justin R.

    2016-01-01

    Anti-platelet drugs are the mainstay of pharmacotherapy for heart attack and stroke prevention, yet improvements are continually sought. Thrombin is the most potent activator of platelets and targeting platelet thrombin receptors (protease-activated receptors; PARs) is an emerging anti-thrombotic approach. Humans express two PARs on their platelets–PAR1 and PAR4. The first PAR1 antagonist was recently approved for clinical use and PAR4 antagonists are in early clinical development. However, pre-clinical studies examining platelet PAR function are challenging because the platelets of non-primates do not accurately reflect the PAR expression profile of human platelets. Mice, for example, express Par3 and Par4. To address this limitation, we aimed to develop a genetically modified mouse that would express the same repertoire of platelet PARs as humans. Here, human PAR1 preceded by a lox-stop-lox was knocked into the mouse Par3 locus, and then expressed in a platelet-specific manner (hPAR1-KI mice). Despite correct targeting and the predicted loss of Par3 expression and function in platelets from hPAR1-KI mice, no PAR1 expression or function was detected. Specifically, PAR1 was not detected on the platelet surface nor internally by flow cytometry nor in whole cell lysates by Western blot, while a PAR1-activating peptide failed to induce platelet activation assessed by either aggregation or surface P-selectin expression. Platelets from hPAR1-KI mice did display significantly diminished responsiveness to thrombin stimulation in both assays, consistent with a Par3-/- phenotype. In contrast to the observations in hPAR1-KI mouse platelets, the PAR1 construct used here was successfully expressed in HEK293T cells. Together, these data suggest ectopic PAR1 expression is not tolerated in mouse platelets and indicate a different approach is required to develop a small animal model for the purpose of any future preclinical testing of PAR antagonists as anti-platelet drugs. PMID

  3. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation

    PubMed Central

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta

    2016-01-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces. To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins. PMID:27248800

  4. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation.

    PubMed

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta; Jakimowicz, Dagmara

    2016-04-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins.

  5. suPAR and Team Nephrology

    PubMed Central

    2014-01-01

    Primary focal segmental glomerulosclerosis (FSGS) accounts for nearly 10 % of patients who require renal replacement therapy. Elevated circulating levels of soluble urokinase receptor (suPAR) have been identified as a biomarker to discriminate primary FSGS from other glomerulopathies. Subsequent reports have questioned the diagnostic utility of this test. In a study in BMC Medicine, Huang et al. demonstrate that urinary soluble urokinase receptor (suPAR) excretion assists in distinguishing primary FSGS from other glomerular diseases, and that high plasma suPAR concentrations are not directly linked to a decline in glomerular filtration rate (GFR). This observation suggests that further investigation of suPAR is warranted in patients with FSGS. It should be interpreted in light of a recent report that B7-1 is expressed in the podocytes of a subset of patients with FSGS, and that blocking this molecule may represent the first successful targeted intervention for this disease. These advances highlight the rapid pace of scientific progress in the field of nephrology. Nephrologists should work together, share resources, and expedite the design of protocols to evaluate these novel biomarkers in a comprehensive and scientifically valid manner. Please see related article http://www.biomedcentral.com/1741-7015/12/81. PMID:24885021

  6. PAR Corneal Topography System (PAR CTS): the clinical application of close-range photogrammetry.

    PubMed

    Belin, M W; Cambier, J L; Nabors, J R; Ratliff, C D

    1995-11-01

    The PAR Corneal Topography System (CTS) is a computer-driven corneal imaging system which uses close-range photogrammetry (rasterphotogrammetry) to measure and produce a topographic map of the corneal surface. The PAR CTS makes direct point-by-point measurements of surface elevation using a stereo-triangulation technique. The CTS uses a grid pattern composed of horizontal and vertical lines spaced about 0.2 mm (200 microns) apart. Each grid intersection comprises a surface feature which can be located in multiple images and used to generate an (x,y,z) coordinate. Unlike placido disc-based videokeratoscopes, the PAR CTS requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. In addition to surface elevation, the PAR CTS computes axial and tangential curvatures and refractive power. Difference maps are available in all curvatures, refractive power, and in absolute elevation.

  7. Specific activation, signalling and secretion profiles of human platelets following PAR-1 and PAR-4 stimulation.

    PubMed

    Nguyen, Kim Anh; Hamzeh-Cognasse, Hind; Laradi, Sandrine; Pozzetto, Bruno; Garraud, Olivier; Cognasse, Fabrice

    2015-01-01

    Blood platelets play a central haemostatic function; however, they also play a role in inflammation and are capable of secreting various cytokines, chemokines and related products. The purpose of this study was to identify subtle variations in platelet physiology using proteomics. We compared the levels of membrane proteins (n = 3), α and δ granule proteins (n = 18), and signalling proteins (n = 30) from unstimulated platelets with those of protease-activated receptor (PAR)-1- and PAR-4-stimulated platelets (n = 10). The vast majority of these proteins responded similarly to PAR-1 or PAR-4 engagement. However, differences were observed within membrane CD40L expressed, and α granule GRO-α and MDC secreted proteins.

  8. Élaboration de films de molécules organiques par ablation par laser UV

    NASA Astrophysics Data System (ADS)

    Hernandez-Perez, M. A.; Garapon, C.; Champeaux, C.; Coleman, A. W.

    2006-12-01

    Les potentialités des méthodes de dépôt par ablation laser (PLD) pour la préparation de films minces de matériaux organiques sont illustrées par un bref rappel bibliographique et par des résultats expérimentaux concernant des molécules d'intérêt biologique (acides aminés, calix-arènes, protéines). Les films sont préparés par PLD avec un laser KrF sans dégradation de la structure chimique des molécules dans une gamme de fluences de quelques dizaines à quelques centaines de mJ/cm2. Les propriétés structurales et optiques des films sont étudiées en fonction de la fluence du laser et mettent en évidence des arrangements moléculaires particuliers induits par cette méthode de dépôt. Le guidage optique a été obtenu pour des films de toutes ces molécules.

  9. Kallikrein 6 Signals through PAR1 and PAR2 to Promote Neuron Injury and Exacerbate Glutamate Neurotoxicity

    PubMed Central

    Yoon, Hyesook; Radulovic, Maja; Wu, Jianmin; Blaber, Sachiko I.; Blaber, Michael; Fehlings, Michael G.; Scarisbrick, Isobel A.

    2014-01-01

    CNS trauma generates a proteolytic imbalance contributing to secondary injury, including axonopathy and neuron degeneration. Kallikrein 6 (Klk6) is a serine protease implicated in neurodegeneration and here we investigate the role of protease activated receptors 1 (PAR1) and PAR2 in mediating these effects. First we demonstrate Klk6 and the prototypical activator of PAR1, thrombin, as well as PAR1 and PAR2, are each elevated in murine experimental traumatic spinal cord injury (SCI) at acute or subacute time points. Recombinant Klk6 triggered ERK1/2 signaling in cerebellar granule neurons and in the NSC34 spinal cord motoneuron cell line, in a PI3K and MEK-dependent fashion. Importantly, lipopeptide inhibitors of PAR1 or PAR2, and PAR1 genetic deletion, each reduced Klk6-ERK1/2 activation. In addition, Klk6 and thrombin promoted degeneration of cerebellar neurons and exacerbated glutamate neurotoxicity. Moreover, genetic deletion of PAR1 blocked thrombin-mediated cerebellar neurotoxicity and reduced the neurotoxic effects of Klk6. Klk6 also increased glutamate-mediated Bim signaling, PARP cleavage and lactate dehydrogenase (LDH) release in NSC34 motoneurons and these effects were blocked by PAR1 and PAR2 lipopeptide inhibitors. Taken together these data point to a novel Klk6-signaling axis in CNS neurons that is mediated by PAR1 and PAR2 and is positioned to contribute to neurodegeneration. PMID:23647384

  10. A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition Assembly

    SciTech Connect

    B Chaudhuri; S Gupta; V Urban; M Chance; R DMello; L Smith; K Lyons; J Gee

    2011-12-31

    Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

  11. A Combined Global and Local Approach to Elucidate Spatial Organization of the Mycobacterial ParB-parS Partition

    SciTech Connect

    Chaudhuri, Barnali; Gupta, Sayan; Urban, Volker S; Chance, Mark; D'Mello, Rhijuta; Smith, Lauren; Lyons, Kelly; Gee, Jessica

    2010-01-01

    Combining diverse sets of data at global (size, shape) and local (residue) scales is an emerging trend for elucidating the organization and function of the cellular assemblies. We used such a strategy, combining data from X-ray and neutron scattering with H/D-contrast variation and X-ray footprinting with mass spectrometry, to elucidate the spatial organization of the ParB-parS assembly from Mycobacterium tuberculosis. The ParB-parS participates in plasmid and chromosome segregation and condensation in predivisional bacterial cells. ParB polymerizes around the parS centromere(s) to form a higher-order assembly that serves to recruit cyto-skeletal ParA ATPases and SMC proteins for chromosome segregation. A hybrid model of the ParB-parS was built by combining and correlating computational models with experiment-derived information about size, shape, position of the symmetry axis within the shape, internal topology, DNA-protein interface, exposed surface patches, and prior knowledge. This first view of the ParB-parS leads us to propose how ParB spread on the chromosome to form a larger assembly.

  12. Host response biomarker in sepsis: suPAR detection.

    PubMed

    Giamarellos-Bourboulis, Evangelos J; Georgitsi, Marianna

    2015-01-01

    Recent studies of our group have shown that suPAR may complement APACHE II score for risk assessment in sepsis. suPAR may be measured in serum of patients by an enzyme immunosorbent assay developed by Virogates (suPARnostic™). Production of suPAR from circulating neutrophils and monocytes may be assessed after isolation of neutrophils and monocytes and ex vivo culture. This is followed by measurement of suPAR in culture supernatants.

  13. Drosophila 14-3-3/PAR-5 is an essential mediator of PAR-1 function in axis formation.

    PubMed

    Benton, Richard; Palacios, Isabel M; St Johnston, Daniel

    2002-11-01

    PAR-1 kinases are required to determine the anterior-posterior (A-P) axis in C. elegans and Drosophila, but little is known about their molecular function. We identified 14-3-3 proteins as Drosophila PAR-1 interactors and show that PAR-1 binds a domain of 14-3-3 distinct from the phosphoserine binding pocket. PAR-1 kinases phosphorylate proteins to generate 14-3-3 binding sites and may therefore directly deliver 14-3-3 to these targets. 14-3-3 mutants display identical phenotypes to par-1 mutants in oocyte determination and the polarization of the A-P axis. Together, these results indicate that PAR-1's function is mediated by the binding of 14-3-3 to its substrates. The C. elegans 14-3-3 protein, PAR-5, is also required for A-P polarization, suggesting that this is a conserved mechanism by which PAR-1 establishes cellular asymmetries.

  14. [Ambroise Paré and Latin].

    PubMed

    Drouin, Emmanuel

    2010-06-01

    We report a study of a medical book written by Antoine Mizaud (Memorabilium utilium, in ac iucundorum aphorismos Arcanorum omnis generis locupletes, perpulchre digestae), which was written in Latin, but has been extensively annotated in French.The book is from the personal collection of one of the physicians of Napoleon III. There is an oral tradition within his family that one of the works in the book had been annotated by Ambroise Paré. We know very little, apart from a few receipts and his signature, about the writing of the master of French surgery. Did he understand the language of Galen? There are many annotated passages in the works of Pare which are in the book. We examine whether these annotations were actually made by Ambroise Paré or whether they were done for him.

  15. [Ambroise Paré in French literature].

    PubMed

    Dumaitre, P

    1995-01-01

    The 16th century by its passionate side has been the favourite one of authors of historical novels in which among the heroes of "cloak and dagger stories" appears sometime Ambroise Paré. Alexandre Dumas (the father) has shown him at the court of Charles IX in La Reine Margot (1845) where he does not however play a great role. On the contrary, Balzac in Le Martyr calviniste (1842) has given him a capital part close to the dying François II, whom he intended to trepanize but had to give up this idea as a consequence of the opposition of the queen-mother Catherine de Médicis. In the present century, Robert Merle in Paris ma bonne ville (Fortune de France, 3, 1980) shows Paré at the time of the Saint Barthélemy.

  16. Les Brulures Chimiques Par Le Laurier Rose

    PubMed Central

    Bakkali, H.; Ababou, M.; Nassim Sabah, T.; Moussaoui, A.; Ennouhi, A.; Fouadi, F.Z.; Siah, S.; Ihrai, H.

    2010-01-01

    Summary Le laurier rose ou Nerium oleander est un arbuste qui pousse naturellement dans les régions méditerranéennes. Au Maroc on le trouve dans les lieux humides. Il est réputé par ses risques de toxicité systémique en cas d'empoisonnement à cause de la présence de deux alcaloïdes, surtout l'oléandrine. La littérature illustre des cas d'utilisation locale des feuilles de cette plante contre la gale, les hémorroïdes et les furoncles. Nous rapportons deux cas de brûlures chimiques par le laurier rose de gravité différente. Cela doit aboutir à une information élargie de la population, ainsi qu'une réglementation stricte de sa commercialisation. PMID:21991211

  17. Critical Role for PAR1 in Kallikrein 6-Mediated Oligodendrogliopathy

    PubMed Central

    Burda, Joshua E.; Radulovic, Maja; Yoon, Hyesook; Scarisbrick, Isobel A.

    2014-01-01

    Kallikrein 6 (Klk6) is a secreted serine protease preferentially expressed by oligodendroglia in CNS white matter. Elevated levels of Klk6 occur in actively demyelinating multiple sclerosis (MS) lesions and in cases of spinal cord injury (SCI), stroke and glioblastoma. Taken with recent evidence establishing Klk6 as a CNS-endogenous activator of protease-activated receptors (PARs), we hypothesized that Klk6 activates a subset of PARs to regulate oligodendrocyte physiology and potentially pathophysiology. Here, primary oligodendrocyte cultures derived from wild type or PAR1-deficient mice and the murine oligodendrocyte cell line, Oli-neu, were used to demonstrate that Klk6 mediates loss of oligodendrocyte processes and impedes morphological differentiation of oligodendrocyte progenitor cells (OPCs) in a PAR1-dependent fashion. Comparable gliopathy was also elicited by the canonical PAR1 agonist, thrombin, as well as PAR1-activating peptides (PAR1-APs). Klk6 also exacerbated ATP-mediated oligodendrogliopathy in vitro, pointing to a potential role in augmenting excitotoxicity. In addition, Klk6 suppressed the expression of proteolipid protein (PLP) RNA in cultured oligodendrocytes by a mechanism involving PAR1-mediated Erk1/2 signaling. Microinjection of PAR1 agonists, including Klk6 or PAR1-APs, into the dorsal column white matter of PAR+/+ but not PAR−/− mice promoted vacuolating myelopathy and a loss of immunoreactivity for myelin basic protein (MBP) and CC-1+ oligodendrocytes. These results demonstrate a functional role for Klk6-PAR1 signaling in oligodendroglial pathophysiology and suggest that PAR1 or PAR1-agonists may represent new targets to moderate demyelination and to promote myelin regeneration in cases of CNS white matter injury or disease. PMID:23832758

  18. Modelisation par elements finis du muscle strie

    NASA Astrophysics Data System (ADS)

    Leonard, Mathieu

    Ce present projet de recherche a permis. de creer un modele par elements finis du muscle strie humain dans le but d'etudier les mecanismes engendrant les lesions musculaires traumatiques. Ce modele constitue une plate-forme numerique capable de discerner l'influence des proprietes mecaniques des fascias et de la cellule musculaire sur le comportement dynamique du muscle lors d'une contraction excentrique, notamment le module de Young et le module de cisaillement de la couche de tissu conjonctif, l'orientation des fibres de collagene de cette membrane et le coefficient de poisson du muscle. La caracterisation experimentale in vitro de ces parametres pour des vitesses de deformation elevees a partir de muscles stries humains actifs est essentielle pour l'etude de lesions musculaires traumatiques. Le modele numerique developpe est capable de modeliser la contraction musculaire comme une transition de phase de la cellule musculaire par un changement de raideur et de volume a l'aide des lois de comportement de materiau predefinies dans le logiciel LS-DYNA (v971, Livermore Software Technology Corporation, Livermore, CA, USA). Le present projet de recherche introduit donc un phenomene physiologique qui pourrait expliquer des blessures musculaires courantes (crampes, courbatures, claquages, etc.), mais aussi des maladies ou desordres touchant le tissu conjonctif comme les collagenoses et la dystrophie musculaire. La predominance de blessures musculaires lors de contractions excentriques est egalement exposee. Le modele developpe dans ce projet de recherche met ainsi a l'avant-scene le concept de transition de phase ouvrant la porte au developpement de nouvelles technologies pour l'activation musculaire chez les personnes atteintes de paraplegie ou de muscles artificiels compacts pour l'elaboration de protheses ou d'exosquelettes. Mots-cles Muscle strie, lesion musculaire, fascia, contraction excentrique, modele par elements finis, transition de phase

  19. A new model for estimating boreal forest fPAR

    NASA Astrophysics Data System (ADS)

    Majasalmi, Titta; Rautiainen, Miina; Stenberg, Pauline

    2014-05-01

    Life on Earth is continuously sustained by the extraterrestrial flux of photosynthetically active radiation (PAR, 400-700 nm) from the sun. This flux is converted to biomass by chloroplasts in green vegetation. Thus, the fraction of absorbed PAR (fPAR) is a key parameter used in carbon balance studies, and is listed as one of the Essential Climate Variables (ECV). Temporal courses of fPAR for boreal forests are difficult to measure, because of the complex 3D structures. Thus, they are most often estimated based on models which quantify the dependency of absorbed radiation on canopy structure. In this study, we adapted a physically-based canopy radiation model into a fPAR model, and compared modeled and measured fPAR in structurally different boreal forest stands. The model is based on the spectral invariants theory, and uses leaf area index (LAI), canopy gap fractions and spectra of foliage and understory as input data. The model differs from previously developed more detailed fPAR models in that the complex 3D structure of coniferous forests is described using an aggregated canopy parameter - photon recollision probability p. The strength of the model is that all model inputs are measurable or available through other simple models. First, the model was validated with measurements of instantaneous fPAR obtained with the TRAC instrument in nine Scots pine, Norway spruce and Silver birch stands in a boreal forest in southern Finland. Good agreement was found between modeled and measured fPAR. Next, we applied the model to predict temporal courses of fPAR using data on incoming radiation from a nearby flux tower and sky irradiance models. Application of the model to simulate diurnal and seasonal values of fPAR indicated that the ratio of direct-to-total incident radiation and leaf area index are the key factors behind the magnitude and variation of stand-level fPAR values.

  20. 2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. HI PAR (ACQUISITION RADAR) TOWER AND ENLISTED MEN (EM) BARRACKS WITH RADAR ATTACHED. - Nike Hercules Missile Battery Summit Site, Battery Control Administration & Barracks Building, Anchorage, Anchorage, AK

  1. Neuroprotective efficacy of poly-arginine R18 and NA-1 (TAT-NR2B9c) peptides following transient middle cerebral artery occlusion in the rat.

    PubMed

    Milani, Diego; Cross, Jane L; Anderton, Ryan S; Blacker, David J; Knuckey, Neville W; Meloni, Bruno P

    2017-01-01

    We examined the efficacy of R18 in a transient MCAO model and compared its effectiveness to the well-characterized neuroprotective NA-1 peptide. R18 and NA-1 peptides were administered intravenously (30, 100, 300, 1000nmol/kg), 60min after the onset of 90min of MCAO. Infarct volume, cerebral swelling and functional outcomes (neurological score, adhesive tape and rota-rod) were measured 24h after MCAO. R18 reduced total infarct volume by 35.1% (p=0.008), 24.8% (p=0.059), 12.2% and 9.6% for the respective 1000 to 30nmol/kg doses, while the corresponding doses of NA-1 reduced lesion volume by 26.1% (p=0.047), 16.6%, 16.5% and 7%, respectively. R18 also reduced hemisphere swelling by between 46.1% (1000 and 300nmol/kg; p=0.009) and 24.4% (100nmol/kg; p=0.066), while NA-1 reduced swelling by 25.7% (1000nmol/kg; p=0.054). In addition, several R18 and NA-1 treatment groups displayed a significant improvement in at least one parameter of the adhesive tape test. These results confirm the neuroprotective properties of R18, and suggest that the peptide is a more effective neuroprotective agent than NA-1. This provides strong justification for the continuing development of R18 as a neuroprotective treatment for stroke.

  2. Taare Zameen Par and dyslexic savants

    PubMed Central

    Chakravarty, Ambar

    2009-01-01

    The film Taare Zameen Par (Stars upon the Ground) portrays the tormented life at school and at home of a child with dyslexia and his eventual success after his artistic talents are discovered by his art teacher at the boarding school. The film hints at a curious neurocognitive phenomenon of creativity in the midst of language disability, as exemplified in the lives of people like Leonardo da Vinci and Albert Einstein, both of whom demonstrated extraordinary creativity even though they were probably affected with developmental learning disorders. It has been hypothesized that a developmental delay in the dominant hemisphere most likely ‘disinhibits’ the nondominant parietal lobe, unmasking talents—artistic or otherwise—in some such individuals. It has been suggested that, in remedial training, children with learning disorders be encouraged to develop such hidden talents to full capacity, rather than be subjected to the usual overemphasis on the correction of the disturbed coded symbol operations. PMID:20142854

  3. Transcriptome profiling reveals links between ParS/ParR, MexEF-OprN, and quorum sensing in the regulation of adaptation and virulence in Pseudomonas aeruginosa

    PubMed Central

    2013-01-01

    Background The ParS/ParR two component regulatory system plays critical roles for multidrug resistance in Pseudomonas aeruginosa. It was demonstrated that in the presence of antimicrobials, ParR enhances bacterial survival by distinct mechanisms including activation of the mexXY efflux genes, enhancement of lipopolysaccharide modification through the arn operon, and reduction of the expression of oprD porin. Results In this study, we report on transcriptomic analyses of P. aeruginosa PAO1 wild type and parS and parR mutants growing in a defined minimal medium. Our transcriptomic analysis provides the first estimates of transcript abundance for the 5570 coding genes in P. aeruginosa PAO1. Comparative transcriptomics of P. aeruginosa PAO1 and par mutants identified a total of 464 genes regulated by ParS and ParR. Results also showed that mutations in the parS/parR system abolished expression of the mexEF-oprN operon by down-regulating the regulatory gene mexS. In addition to the known effects on drug resistance genes, transcript abundances of the quorum sensing genes (rhlIR and pqsABCDE-phnAB) were higher in both parS and parR mutants. In accordance with these results, a significant portion of the ParS/ParR regulated genes belonged to the MexEF-OprN and quorum sensing regulons. Deletion of the par genes also led to increased phenazine production and swarming motility, consistent with the up-regulation of the phenazine and rhamnolipid biosynthetic genes, respectively. Conclusion Our results link the ParS/ParR two component signal transduction system to MexEF-OprN and quorum sensing systems in P. aeruginosa. These results expand our understanding of the roles of the ParS/ParR system in the regulation of gene expression in P. aeruginosa, especially in the absence of antimicrobials. PMID:24034668

  4. Recombination in the Human Pseudoautosomal Region PAR1

    PubMed Central

    Hinch, Anjali G.; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R.

    2014-01-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome. PMID:25033397

  5. Recombination in the human Pseudoautosomal region PAR1.

    PubMed

    Hinch, Anjali G; Altemose, Nicolas; Noor, Nudrat; Donnelly, Peter; Myers, Simon R

    2014-07-01

    The pseudoautosomal region (PAR) is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome.

  6. Megestrol acetate NCD oral suspension -- Par Pharmaceutical: megestrol acetate nanocrystal dispersion oral suspension, PAR 100.2, PAR-100.2.

    PubMed

    2007-01-01

    Par Pharmaceutical has developed megestrol acetate (Megace ES) oral suspension for the treatment of anorexia, cachexia and a significant weight loss associated with AIDS. Par Pharmaceutical used Elan Corporation's NanoCrystal Dispersion (NCD) technology to develop an advanced, concentrated formulation of megestrol acetate with improved bioavailability, more rapid onset of action, more convenient dosing and a lower dosing regimen compared with the original marketed formulation of megestrol acetate oral suspension. Patients are administered a teaspoon (5mL) of the new NCD formulation once daily, compared with a daily 20mL dosage cup of the original formulation. The new megestrol acetate NCD formulation represents a line-extension of Par's megestrol acetate oral suspension (800mg/20mL, Megace O/S) that has been marketed for anorexia, cachexia and AIDS-related weight loss since July 2001. Par's megestrol acetate is the generic version of Bristol-Myers Squibb's Megace Oral Suspension. NanoCrystal Dispersion (NCD) is a trademark of Elan Corporation. Par Pharmaceutical will market megestol acetate NCD oral suspension under the Megace brand name. The company licensed the Megace name from Bristol-Myers Squib in August 2003. The US FDA approved megestrol acetate oral suspension (625 mg/mL) in July 2005 for the treatment of anorexia, cachexia or a significant, unexplained weight loss in patients with AIDS. The NDA for the product was accepted for review by the agency in September 2004, following its submission in June of that year.Par Pharmaceutical commenced the first of two phase III clinical trials of megestrol acetate oral suspension (PAR 100.2) in cancer-induced anorexia in the first quarter of 2006. However, this trial was discontinued in September 2006 because of slow patient enrolment. The company intends to discuss future development options in this indication with the FDA.New formulations or dosage forms of megestrol acetate concentrated suspension are also in

  7. Megestrol acetate NCD oral suspension--Par Pharmaceutical: megestrol acetate nanocrystal dispersion oral suspension, PAR 100.2, PAR-100.2.

    PubMed

    2007-01-01

    Par Pharmaceutical has developed megestrol acetate (Megace ES) oral suspension for the treatment of anorexia, cachexia and a significant weight loss associated with AIDS. Par Pharmaceutical used Elan Corporation's NanoCrystal Dispersion (NCD) technology to develop an advanced, concentrated formulation of megestrol acetate with improved bioavailability, more rapid onset of action, more convenient dosing and a lower dosing regimen compared with the original marketed formulation of megestrol acetate oral suspension. Patients are administered a teaspoon (5mL) of the new NCD formulation once daily, compared with a daily 20mL dosage cup of the original formulation. The new megestrol acetate NCD formulation represents a line-extension of Par's megestrol acetate oral suspension (800mg/20mL, Megace O/S) that has been marketed for anorexia, cachexia and AIDS-related weight loss since July 2001. Par's megestrol acetate is the generic version of Bristol-Myers Squibb's Megace Oral Suspension. NanoCrystal Dispersion (NCD) is a trademark of Elan Corporation. Par Pharmaceutical will market megestol acetate NCD oral suspension under the Megace brand name. The company licensed the Megace name from Bristol-Myers Squib in August 2003. The US FDA approved megestrol acetate oral suspension (625 mg/mL) in July 2005 for the treatment of anorexia, cachexia or a significant, unexplained weight loss in patients with AIDS. The NDA for the product was accepted for review by the agency in September 2004, following its submission in June of that year.Par Pharmaceutical commenced the first of two phase III clinical trials of megestrol acetate oral suspension (PAR 100.2) in cancer-induced anorexia in the first quarter of 2006. However, this trial was discontinued in September 2006 because of slow patient enrolment. The company intends to discuss future development options in this indication with the FDA.New formulations or dosage forms of megestrol acetate concentrated suspension are also in

  8. Condensation and localization of the partitioning protein ParB on the bacterial chromosome.

    PubMed

    Broedersz, Chase P; Wang, Xindan; Meir, Yigal; Loparo, Joseph J; Rudner, David Z; Wingreen, Ned S

    2014-06-17

    The ParABS system mediates chromosome segregation and plasmid partitioning in many bacteria. As part of the partitioning mechanism, ParB proteins form a nucleoprotein complex at parS sites. The biophysical basis underlying ParB-DNA complex formation and localization remains elusive. Specifically, it is unclear whether ParB spreads in 1D along DNA or assembles into a 3D protein-DNA complex. We show that a combination of 1D spreading bonds and a single 3D bridging bond between ParB proteins constitutes a minimal model for a condensed ParB-DNA complex. This model implies a scaling behavior for ParB-mediated silencing of parS-flanking genes, which we confirm to be satisfied by experimental data from P1 plasmids. Furthermore, this model is consistent with experiments on the effects of DNA roadblocks on ParB localization. Finally, we show experimentally that a single parS site is necessary and sufficient for ParB-DNA complex formation in vivo. Together with our model, this suggests that ParB binding to parS triggers a conformational switch in ParB that overcomes a nucleation barrier. Conceptually, the combination of spreading and bridging bonds in our model provides a surface tension ensuring the condensation of the ParB-DNA complex, with analogies to liquid-like compartments such as nucleoli in eukaryotes.

  9. Condensation and localization of the partitioning protein ParB on the bacterial chromosome

    PubMed Central

    Broedersz, Chase P.; Wang, Xindan; Meir, Yigal; Loparo, Joseph J.; Rudner, David Z.; Wingreen, Ned S.

    2014-01-01

    The ParABS system mediates chromosome segregation and plasmid partitioning in many bacteria. As part of the partitioning mechanism, ParB proteins form a nucleoprotein complex at parS sites. The biophysical basis underlying ParB–DNA complex formation and localization remains elusive. Specifically, it is unclear whether ParB spreads in 1D along DNA or assembles into a 3D protein–DNA complex. We show that a combination of 1D spreading bonds and a single 3D bridging bond between ParB proteins constitutes a minimal model for a condensed ParB–DNA complex. This model implies a scaling behavior for ParB-mediated silencing of parS-flanking genes, which we confirm to be satisfied by experimental data from P1 plasmids. Furthermore, this model is consistent with experiments on the effects of DNA roadblocks on ParB localization. Finally, we show experimentally that a single parS site is necessary and sufficient for ParB–DNA complex formation in vivo. Together with our model, this suggests that ParB binding to parS triggers a conformational switch in ParB that overcomes a nucleation barrier. Conceptually, the combination of spreading and bridging bonds in our model provides a surface tension ensuring the condensation of the ParB–DNA complex, with analogies to liquid-like compartments such as nucleoli in eukaryotes. PMID:24927534

  10. Scleral Buckling for Rhegmatogenous Retinal Detachment Associated with Pars Planitis

    PubMed Central

    Ahn, Jae Kyoun

    2016-01-01

    Purpose. To evaluate the surgical outcome of scleral buckling (SB) in rhegmatogenous retinal detachment (RRD) patients associated with pars planitis. Methods. Retrospective review of RRD patients (32 eyes of pars planitis RRD and 180 eyes of primary RRD) who underwent SB. We compared primary and final anatomical success rates and visual outcomes between two groups. Results. Primary and final anatomical success were achieved in 25 (78.1%) and 31 (96.8%) eyes in the pars planitis RRD group and in 167 eyes (92.7%) and 176 eyes (97.7%) in primary RRD group, respectively. Both groups showed significant visual improvement (p < 0.001) and there were no significant differences in final visual acuity. Pars planitis RRD group was associated with higher rate of postoperative proliferative vitreoretinopathy (PVR) development (12.5% versus 2.8%, p = 0.031). Pars planitis and high myopia were significant preoperative risk factors and pseudophakia was borderline risk for primary anatomical failure after adjusting for various clinical factors. Conclusions. Pars planitis associated RRD showed inferior primary anatomical outcome after SB due to postoperative PVR development. However, final anatomical and visual outcomes were favorable. RRD cases associated with pars planitis, high myopia, and pseudophakia might benefit from different surgical approaches, such as combined vitrectomy and SB. PMID:27688907

  11. The Pars Triangularis in Dyslexia and ADHD

    PubMed Central

    Kibby, Michelle Y.; Kroese, Judith M.; Krebbs, Hillery; Hill, Crystal E.; Hynd, George W.

    2009-01-01

    Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one of the purposes of this study was to examine the structure of the PT in dyslexia and ADHD. The other purposes included examining the PT in relation to overall expressive language ability and in relation to several specific linguistic functions given language functioning often is affected in both dyslexia and ADHD. Participants included 50 children: 10 with dyslexia, 15 with comorbid dyslexia/ADHD, 15 with ADHD, and 10 controls. Using a 2 (dyslexia or not) X 2 (ADHD or not) MANCOVA, findings revealed PT length and shape were comparable between those with and without dyslexia. However, children with ADHD had smaller right PT lengths than those without ADHD, and right anterior ascending ramus length was related to attention problems in the total sample. In terms of linguistic functioning, presence of an extra sulcus in the left PT was related to poor expressive language ability. In those with adequate expressive language functioning, left PT length was related to phonological awareness, phonological short-term memory and rapid automatic naming (RAN). Right PT length was related to RAN and semantic processing. Further work on PT morphology in relation to ADHD and linguistic functioning is warranted. PMID:19356794

  12. Multi-scale photoacoustic remote sensing (PARS) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Haji Reza, Parsin; Bell, Kevan; Shi, W.; Zemp, Roger J.

    2016-03-01

    We introduce a novel multi-scale photoacoustic remote sensing (PARS) imaging system. Our system can provide optical resolution details for superficial structures as well as acoustic resolution for deep-tissue imaging down to 5 cm, in a non-contact setting. PARS system does not require any contact with the sample or ultrasound coupling medium. The optical resolution PARS (OR-OARS) system uses optically focused pulsed excitation with optical detection of photoacoustic signatures using a long-coherence interrogation beam co-focused and co-scanned with the excitation spot. In the OR-PARS initial pressures are sampled right at their subsurface origin where acoustic pressures are largest. The Acoustic resolution PARS (AR-PARS) picks up the surface oscillation of the tissue caused by generated photoacoustic signal using a modified version of Michelson interferometry. By taking advantage of 4-meters polarization maintaining single-mode fiber and a green fiber laser we have generated a multi-wavelength source using stimulated Raman scattering. Remote functional imaging using this multi-wavelength excitation source and PARS detection mechanism has been demonstrated. The oxygen saturation estimations are shown for both phantom and in vivo studies. Images of blood vessel structures for an In vivo chicken embryo model is demonstrated. The Phantom studies indicates ~3µm and ~300µm lateral resolution for OR-PARS and AR-PARS respectively. To the best of our knowledge this is the first dual modality non-contact optical and acoustic resolution system used for in vivo imaging.

  13. Predicted PAR1 inhibitors from multiple computational methods

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Liu, Jinfeng; Zhu, Tong; Zhang, Lujia; He, Xiao; Zhang, John Z. H.

    2016-08-01

    Multiple computational approaches are employed in order to find potentially strong binders of PAR1 from the two molecular databases: the Specs database containing more than 200,000 commercially available molecules and the traditional Chinese medicine (TCM) database. By combining the use of popular docking scoring functions together with detailed molecular dynamics simulation and protein-ligand free energy calculations, a total of fourteen molecules are found to be potentially strong binders of PAR1. The atomic details in protein-ligand interactions of these molecules with PAR1 are analyzed to help understand the binding mechanism which should be very useful in design of new drugs.

  14. View from northeast to southwest of PAR site sentry station; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from northeast to southwest of PAR site sentry station; formerly the bachelor's enlisted men's quarter (BEQ) - Stanley R. Mickelsen Safeguard Complex, Sentry Station, North of Second Avenue & West of Electrical Switch Station No. 2, Nekoma, Cavalier County, ND

  15. PARS: Programs for Analysis and Resizing of Structures, user manual

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.; Prasad, B.; Tsach, U.

    1979-01-01

    PARS processors and their use, flutter analysis, sensitivity analysis for stresses, and resizing are presented. Design variable definition and interface with finite element model, static constraints and their derivatives, flutter derivatives, and optimization are discussed.

  16. View from southwest to northeast of PAR site fresh water ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from southwest to northeast of PAR site fresh water pump house - Stanley R. Mickelsen Safeguard Complex, Fresh Water Pump House, In Limited Access Area, on Patrol Road next to Open Storage Reservoir No. 736, Nekoma, Cavalier County, ND

  17. Croissance epitaxiale de GaAs sur substrats de Ge par epitaxie par faisceaux chimiques

    NASA Astrophysics Data System (ADS)

    Belanger, Simon

    La situation energetique et les enjeux environnementaux auxquels la societe est confrontee entrainent un interet grandissant pour la production d'electricite a partir de l'energie solaire. Parmi les technologies actuellement disponibles, la filiere du photovoltaique a concentrateur solaire (CPV pour concentrator photovoltaics) possede un rendement superieur et mi potentiel interessant a condition que ses couts de production soient competitifs. La methode d'epitaxie par faisceaux chimiques (CBE pour chemical beam epitaxy) possede plusieurs caracteristiques qui la rendent interessante pour la production a grande echelle de cellules photovoltaiques a jonctions multiples a base de semi-conducteurs III-V. Ce type de cellule possede la meilleure efficacite atteinte a ce jour et est utilise sur les satellites et les systemes photovoltaiques a concentrateur solaire (CPV) les plus efficaces. Une des principales forces de la technique CBE se trouve dans son potentiel d'efficacite d'utilisation des materiaux source qui est superieur a celui de la technique d'epitaxie qui est couramment utilisee pour la production a grande echelle de ces cellules. Ce memoire de maitrise presente les travaux effectues dans le but d'evaluer le potentiel de la technique CBE pour realiser la croissance de couches de GaAs sur des substrats de Ge. Cette croissance constitue la premiere etape de fabrication de nombreux modeles de cellules solaires a haute performance decrites plus haut. La realisation de ce projet a necessite le developpement d'un procede de preparation de surface pour les substrats de germanium, la realisation de nombreuses sceances de croissance epitaxiale et la caracterisation des materiaux obtenus par microscopie optique, microscopie a force atomique (AFM), diffraction des rayons-X a haute resolution (HRXRD), microscopie electronique a transmission (TEM), photoluminescence a basse temperature (LTPL) et spectrometrie de masse des ions secondaires (SIMS). Les experiences ont permis

  18. Molecular Mechanisms of Par-4-Induced Apoptosis in Prostate Cancer

    DTIC Science & Technology

    2007-05-01

    Sambrook J, Fritsch EF, Maniatis T. (1989). Molecular Cloning : A Laboratory Manual (Cold Spring Harbor, New York: Cold Spring Harbor Laboratory...AD_________________ Award Number: W81XWH-05-1-0622 TITLE: Molecular Mechanisms of Par-4-Induced...SUBTITLE 5a. CONTRACT NUMBER Molecular Mechanisms of Par-4-Induced Apoptosis in Prostate Cancer 5b. GRANT NUMBER W81XWH-05-1-0622 5c. PROGRAM

  19. Stabilization of Cell Polarity by the C. elegans RING Protein PAR-2

    PubMed Central

    Hao, Yingsong; Boyd, Lynn; Seydoux, Geraldine

    2006-01-01

    Summary Asymmetric localization of PAR proteins is a hallmark of polarized cells, but the mechanisms that create PAR asymmetry are not well understood. In the C. elegans zygote, PAR asymmetry is initiated by a transient actomyosin contraction, which sweeps the PAR-3/PAR-6/PKC-3 complex toward the anterior pole of the egg. The RING finger protein PAR-2 accumulates in a complementary pattern in the posterior cortex. Here we present evidence that PAR-2 participates in a feedback loop to stabilize polarity. PAR-2 is a target of the PKC-3 kinase and is excluded from the anterior cortex by PKC-3-dependent phosphorylation. The RING domain of PAR-2 is required to overcome inhibition by PKC-3 and stabilize PAR-2 on the posterior cortex. Cortical PAR-2 in turn prevents PAR-3/PAR-6/PKC-3 from returning to the posterior, in a PAR-1- and PAR-5-dependent manner. Our findings suggest that reciprocal inhibitory interactions among PAR proteins stabilize polarity by reinforcing an initial asymmetry in PKC-3. PMID:16459299

  20. Pars Planitis: Epidemiology, Clinical Characteristics, Management and Visual Prognosis

    PubMed Central

    Ozdal, Pinar Cakar; Berker, Nilufer; Tugal-Tutkun, Ilknur

    2015-01-01

    Pars planitis is an idiopathic chronic intermediate uveitis which predominantly affects children and adolescents, and accounts for 5-26.7% of pediatric uveitis. Although an autoimmune process with a genetic predisposition has been suggested, its etiology still remains unknown. The most common presenting symptoms are floaters and blurred vision. Diffuse vitreous cells, haze, snowballs and snowbanks are typical findings of pars planitis. Peripheral retinal vasculitis, optic disc edema and anterior segment inflammation are other well-known findings. Although pars planitis is known to be a benign form of uveitis in most cases, it may become a potentially blinding disease due to complications including cataract, cystoid macular edema, vitreous opacities and optic disc edema. Cystoid macular edema is the most common cause of visual morbidity. Band keratopathy, epiretinal membrane formation, vitreous condensation, neovascularizations, vitreous hemorrhage, retinal detachment, cyclitic membranes, glaucoma and amblyopia may develop as a consequence of the chronic course of the disease. Exclusion of infectious and non-infectious causes which may present with intermediate uveitis is of utmost importance before starting treatment. Treatment of pars planitis has been a controversial issue. There is no consensus specifically for treatment of cases with minimal inflammation and relatively good visual acuity. However, current experience shows that pars planitis may cause severe inflammation and needs an aggressive treatment. A stepladder approach including corticosteroids, immunosupressive agents, anti-tumor necrosis factor-alpha and pars plana vitrectomy and/or laser photocoagulation is the most commonly used method for treatment of pars planitis. Adequate control of inflammation and prompt detection of associated complications are crucial in order to improve the overall prognosis of the disease. PMID:27051493

  1. Par Pond vegetation status Summer 1995 -- June survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-06-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the shoreline aquatic plant communities in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level, indicated that much of the original plant communities and the intermediate shoreline communities present on the exposed sediments have been lost. The extensive old-field and emergent marsh communities that were present on the exposed shoreline during the drawdown have been flooded and much of the pre-drawdown Par Pond aquatic plant communities have not had sufficient time for re-establishment. The shoreline does, however, have extensive beds of maidencane which extend from the shoreline margin to areas as deep as 2 and perhaps 3 meters. Scattered individual plants of lotus and watershield are common and may indicate likely directions of future wetland development in Par Pond. In addition, within isolated coves, which apparently received ground water seepage and/or stream surface flows during the period of the Par Pond draw down, extensive beds of waterlilies and spike rush are common. Invasion of willow and red maple occurred along the lake shoreline as well. Although not absent from this survey, evidence of the extensive redevelopment of the large cattail and eel grass beds was not observed in this first survey of Par Pond. Future surveys during the growing seasons of 1995, 1996, and 1997 along with the evaluation of satellite date to map the areal extent of the macrophyte beds of Par Pond are planned.

  2. Par Pond vegetation status Summer 1995 -- September survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-09-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this mid-September survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maidencane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys during the late growing seasons of 1995, and throughout 1996 and 1997, along with the evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

  3. Par Pond vegetation status Summer 1995 -- October survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-11-01

    The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this late October survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maiden cane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned.

  4. Couches Minces de Titanate de Baryum Par Depot Organometallique

    NASA Astrophysics Data System (ADS)

    Ousi Benomar, Wahib

    1993-01-01

    Nous avons demontre la possibilite de realiser des couches minces de titanate de baryum par depot organometallique. Les films sont obtenus apres dissolution d'organometalliques choisis dans un solvant et une cuisson a une temperature determinee par thermogravimetrie. Apres un second traitement thermique a des temperatures plus elevees, les echantillons presentent une structure polycristalline tetragonale; les cristallites sont observes par microscopie electronique a balayage. La mesure de la constante dielectrique a permis de mettre en evidence une transition de phase de la structure tetragonale a la structure cubique a une temperature d'environ 125^circC. Les mesures d'indice ont ete effectuees. On note une augmentation de l'indice de refraction des films avec la temperature indiquant une meilleure densification des films. Nous avons aussi montre qu'il etait possible d'utiliser ce materiau en tant que guide d'onde optique pour pouvoir exploiter ses proprietes electrooptiques dans l'avenir.

  5. Protease-activated receptor-2 (PAR2) in cardiovascular system.

    PubMed

    Bucci, Mariarosaria; Roviezzo, Fiorentina; Cirino, Giuseppe

    2005-10-01

    Vascular system is constituted by a complex and articulate network, e.g. arteries, arterioles, venules and veins, that requires a high degree of coordination between different elemental cell types. Proteinase-activated receptors (PARs) constitute a recent described family of 7-transmembrane G protein-coupled receptors that are activated by proteolysis. In recent years several evidence have been accumulated for an involvement of this receptor in the response to endothelial injury in vitro and in vivo experimental settings suggesting a role for PAR2 in the pathophysiology of cardiovascular system. This review will deal with the role of PAR2 receptor in the cardiovascular system analyzing both in vivo and in vitro published data. In particular this review will deal with the role of this receptor in vascular reactivity, ischemia/reperfusion injury, coronary atherosclerotic lesions and angiogenesis.

  6. Both PHYTOCHROME RAPIDLY REGULATED1 (PAR1) and PAR2 Promote Seedling Photomorphogenesis in Multiple Light Signaling Pathways1[C][W][OPEN

    PubMed Central

    Zhou, Peng; Song, Meifang; Yang, Qinghua; Su, Liang; Hou, Pei; Guo, Lin; Zheng, Xu; Xi, Yulin; Meng, Fanhua; Xiao, Yang; Yang, Li; Yang, Jianping

    2014-01-01

    Arabidopsis (Arabidopsis thaliana) seedlings undergo photomorphogenesis in the light and etiolation in the dark. Light-activated photoreceptors transduce the light signals through a series of photomorphogenesis promoting or repressing factors to modulate many developmental processes in plants, such as photomorphogenesis and shade avoidance. CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) is a conserved RING finger E3 ubiquitin ligase, which mediates degradation of several photomorphogenesis promoting factors, including ELONGATED HYPOCOTYL5 (HY5) and LONG HYPOCOTYL IN FAR-RED1 (HFR1), through a 26S proteasome-dependent pathway. PHYTOCHROME RAPIDLY REGULATED1 (PAR1) was first detected as an early repressed gene in both phytochrome A (phyA)-mediated far-red and phyB-mediated red signaling pathways, and subsequent studies showed that both PAR1 and PAR2 are negative factors of shade avoidance in Arabidopsis. However, the role of PAR1 and PAR2 in seedling deetiolation, and their relationships with other photomorphogenesis promoting and repressing factors are largely unknown. Here, we confirmed that both PAR1 and PAR2 redundantly enhance seedling deetiolation in multiple photoreceptor signaling pathways. Their transcript abundances are repressed by phyA, phyB, and cryptochrome1 under far-red, red, and blue light conditions, respectively. Both PAR1 and PAR2 act downstream of COP1, and COP1 mediates the degradation of PAR1 and PAR2 through the 26S proteasome pathway. Both PAR1 and PAR2 act in a separate pathway from HY5 and HFR1 under different light conditions, except for sharing in the same pathway with HFR1 under far-red light. Together, our results substantiate that PAR1 and PAR2 are positive factors functioning in multiple photoreceptor signaling pathways during seedling deetiolation. PMID:24335334

  7. Traumatisme de la main par injection a haute pression

    PubMed Central

    Mabchoure, K.; Diouri, M.; Bahechar, N.; Chlihi, A.

    2016-01-01

    Summary Les traumatismes de la main par injection à haute pression sont des accidents relativement rares et souvent mal connus par le praticien. Les lésions qui dépendent du produit injecté et du site d’injection sont pourvoyeuses de séquelles esthétiques et fonctionnelles lourdes. Le traitement repose sur la chirurgie, l’antibiothérapie et la rééducation précoce et spécifique. Nous rapportons notre expérience ainsi qu’une revue de la littérature. PMID:27857654

  8. PAR-3 oligomerization may provide an actin-independent mechanism to maintain distinct par protein domains in the early Caenorhabditis elegans embryo.

    PubMed

    Dawes, Adriana T; Munro, Edwin M

    2011-09-21

    Par proteins establish discrete intracellular spatial domains to polarize many different cell types. In the single-cell embryo of the nematode worm Caenorhabditis elegans, the segregation of Par proteins is crucial for proper division and cell fate specification. Actomyosin-based cortical flows drive the initial formation of anterior and posterior Par domains, but cortical actin is not required for the maintenance of these domains. Here we develop a model of interactions between the Par proteins that includes both mutual inhibition and PAR-3 oligomerization. We show that this model gives rise to a bistable switch mechanism, allowing the Par proteins to occupy distinct anterior and posterior domains seen in the early C. elegans embryo, independent of dynamics or asymmetries in the actin cortex. The model predicts a sharp loss of cortical Par protein asymmetries during gradual depletion of the Par protein PAR-6, and we confirm this prediction experimentally. Together, these results suggest both mutual inhibition and PAR-3 oligomerization are sufficient to maintain distinct Par protein domains in the early C. elegans embryo.

  9. BOREAS RSS-10 TOMS Circumpolar One-Degree PAR Images

    NASA Technical Reports Server (NTRS)

    Dye, Dennis G.; Holben, Brent; Nickeson, Jaime (Editor); Hall, Forrest G. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Remote Sensing Science (RSS)-10 team investigated the magnitude of daily, seasonal, and yearly variations of Photosynthetically Active Radiation (PAR) from ground and satellite observations. This data set contains satellite estimates of surface-incident PAR (400-700 nm, MJ/sq m) at one-degree spatial resolution. The spatial coverage is circumpolar from latitudes of 41 to 66 degrees north. The temporal coverage is from May through September for years 1979 through 1989. Eleven-year statistics are also provided: (1) mean, (2) standard deviation, and (3) coefficient of variation for 1979-89. The PAR estimates were derived from the global gridded ultraviolet reflectivity data product (average of 360, 380 nm) from the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS). Image mask data are provided for identifying the boreal forest zone, and ocean/land and snow/ice-covered areas. The data are available as binary image format data files. The PAR data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  10. Par Pond vegetation status summer 1995 - July survey descriptive summary

    SciTech Connect

    Mackey, H.E. Jr.; Riley, R.S.

    1995-07-01

    A survey of the emergent shoreline aquatic plant, communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet (61 meters) above mean sea level, and continued with this July survey. Aquatic plant communities, similar to the pre-drawdown Par Pond communities, are becoming reestablished. Beds of maidencane (Panicum hemitomon), lotus (Nelumbo lutea), water lily (Nymphaea odorata), and watershield (Brasenia schreberi) are now extensive and well established. In addition, within isolated coves, extensive beds of water lilies and spike-rush (Eleocharis sp.) are common. Cattail occurrence has increased since refill, but large beds common to Par Pond prior to the drawdown have not formed. Invasion of willow (Salix sp.) and red maple (Acer rubrum) occurred along the lake shoreline during drawdown. The red maples along the present shoreline are beginning to show evidence of stress and mortality from flooding over the past four months. Some of the willows appear to be stressed as well. The loblolly pines (Pinus taeda), which were flooded in all but the shallow shoreline areas, are now dead. Future surveys are planned for the growing seasons of 1995, 1996, and 1997, along with the evaluation of satellite data for mapping the areal extent of the macrophyte beds of Par Pond.

  11. Radiological impact of Par Pond drawdown from liquid effluent pathways

    SciTech Connect

    Carlton, W.H.; Hamby, D.M.

    1991-10-25

    The water level of Par Pond has been lowered over the past several months to reduce the effects in the event of catastrophic dam failure while assessing the condition of the dam and determining if repairs are necessary. In lowering the level of Par Pond, 60 billion liters of water containing low levels of tritium and cesium-137 were discharged to several onsite streams. SRS surface streams flow to the Savannah River. An assessment made to determine the total amount of tritium and Cs-137 discharged and to estimate the consequences to downstream Savannah River users. It is estimated that a total of 160 curies of tritium were displaced from Par Pond to the Savannah River between June 28, 1991 and September 19, 1991. This release could hypothetically result in a maximum individual dose of 3. 2{times}10{sup {minus}4} mrem and a total (80-km and drinking water populations) population dose of 1.4{times}10{sup {minus}2} person-rem. Likewise, a maximum individual dose of 5.0{times}10{sup {minus}2} mrem and a total population dose of 1.7{times}10{sup {minus}1} person- rem are predicted as a result of an estimated 0.21 curies of Cs-137 being discharged from Par Pond to the Savannah River.

  12. Are You Up to PAR? (Program Administrative Review).

    ERIC Educational Resources Information Center

    Southwest Regional Resource Center, Salt Lake City, UT.

    The document focuses on the workings of PAR (Program Administrative Review), a method by which local education agencies (LEAs) and state operated programs (SOPs) in Utah can conduct ongoing self-evaluation and identify areas where additional efforts are needed to improve the quality of programs and services for handicapped children. It is…

  13. Promiscuous stimulation of ParF protein polymerization by heterogeneous centromere binding factors.

    PubMed

    Machón, Cristina; Fothergill, Timothy J G; Barillà, Daniela; Hayes, Finbarr

    2007-11-16

    The segrosome is the nucleoprotein complex that mediates accurate segregation of bacterial plasmids. The segrosome of plasmid TP228 comprises ParF and ParG proteins that assemble on the parH centromere. ParF, which exemplifies one clade of the ubiquitous ParA superfamily of segregation proteins, polymerizes extensively in response to ATP binding. Polymerization is modulated by the ParG centromere binding factor (CBF). The segrosomes of plasmids pTAR, pVT745 and pB171 include ParA homologues of the ParF subgroup, as well as diverse homodimeric CBFs with no primary sequence similarity to ParG, or each other. Centromere binding by these analogues is largely specific. Here, we establish that the ParF homologues of pTAR and pB171 filament modestly with ATP, and that nucleotide hydrolysis is not required for this polymerization, which is more prodigious when the cognate CBF is also present. By contrast, the ParF homologue of plasmid pVT745 did not respond appreciably to ATP alone, but polymerized extensively in the presence of both its cognate CBF and ATP. The co-factors also stimulated nucleotide-independent polymerization of cognate ParF proteins. Moreover, apart from the CBF of pTAR, the disparate ParG analogues promoted polymerization of non-cognate ParF proteins suggesting that filamentation of the ParF proteins is enhanced by a common mechanism. Like ParG, the co-factors may be modular, possessing a centromere-specific interaction domain linked to a flexible region containing determinants that promiscuously stimulate ParF polymerization. The CBFs appear to function as bacterial analogues of formins, microtubule-associated proteins or related ancillary factors that regulate eucaryotic cytoskeletal dynamics.

  14. Re-Signifying Participatory Action Research (PAR) in Higher Education: What Does "P" Stand for in PAR?

    ERIC Educational Resources Information Center

    Santos, Doris

    2016-01-01

    While carrying out a study aimed at understanding the contribution of participatory action research (PAR) to the political realm in contemporary higher education, a problematic situation was found when doing a literature review in the field of action research. This problem concerns the intermittent appearance of the "participatory"…

  15. Targeting a Proteinase-Activated Receptor 4 (PAR4) Carboxyl Terminal Motif to Regulate Platelet Function.

    PubMed

    Ramachandran, Rithwik; Mihara, Koichiro; Thibeault, Pierre; Vanderboor, Christina M; Petri, Björn; Saifeddine, Mahmoud; Bouvier, Michel; Hollenberg, Morley D

    2017-04-01

    Thrombin initiates human platelet aggregation by coordinately activating proteinase-activated receptors (PARs) 1 and 4. However, targeting PAR1 with an orthosteric-tethered ligand binding-site antagonist results in bleeding, possibly owing to the important role of PAR1 activation on cells other than platelets. Because of its more restricted tissue expression profile, we have therefore turned to PAR4 as an antiplatelet target. We have identified an intracellular PAR4 C-terminal motif that regulates calcium signaling and β-arrestin interactions. By disrupting this PAR4 calcium/β-arrestin signaling process with a novel cell-penetrating peptide, we were able to inhibit both thrombin-triggered platelet aggregation in vitro and clot consolidation in vivo. We suggest that targeting PAR4 represents an attractive alternative to blocking PAR1 for antiplatelet therapy in humans.

  16. ParCAT: A Parallel Climate Analysis Toolkit

    NASA Astrophysics Data System (ADS)

    Haugen, B.; Smith, B.; Steed, C.; Ricciuto, D. M.; Thornton, P. E.; Shipman, G.

    2012-12-01

    Climate science has employed increasingly complex models and simulations to analyze the past and predict the future of our climate. The size and dimensionality of climate simulation data has been growing with the complexity of the models. This growth in data is creating a widening gap between the data being produced and the tools necessary to analyze large, high dimensional data sets. With single run data sets increasing into 10's, 100's and even 1000's of gigabytes, parallel computing tools are becoming a necessity in order to analyze and compare climate simulation data. The Parallel Climate Analysis Toolkit (ParCAT) provides basic tools that efficiently use parallel computing techniques to narrow the gap between data set size and analysis tools. ParCAT was created as a collaborative effort between climate scientists and computer scientists in order to provide efficient parallel implementations of the computing tools that are of use to climate scientists. Some of the basic functionalities included in the toolkit are the ability to compute spatio-temporal means and variances, differences between two runs and histograms of the values in a data set. ParCAT is designed to facilitate the "heavy lifting" that is required for large, multidimensional data sets. The toolkit does not focus on performing the final visualizations and presentation of results but rather, reducing large data sets to smaller, more manageable summaries. The output from ParCAT is provided in commonly used file formats (NetCDF, CSV, ASCII) to allow for simple integration with other tools. The toolkit is currently implemented as a command line utility, but will likely also provide a C library for developers interested in tighter software integration. Elements of the toolkit are already being incorporated into projects such as UV-CDAT and CMDX. There is also an effort underway to implement portions of the CCSM Land Model Diagnostics package using ParCAT in conjunction with Python and gnuplot. Par

  17. Is There an "F" in Your PAR? Understanding, Teaching and Doing Action Research

    ERIC Educational Resources Information Center

    Lorenzetti, Liza; Walsh, Christine Ann

    2014-01-01

    Participatory Action Research (PAR) is increasingly recognized within academic research and pedagogy. What are the benefits of including feminism within participatory action research and teaching? In responding to this question, we discuss the similarities and salient differences between PAR and feminist informed PAR (FPAR). There are eight themes…

  18. Intraoperative raster photogrammetry--the PAR Corneal Topography System.

    PubMed

    Belin, M W

    1993-01-01

    The PAR Corneal Topography System (CTS) is a computer-driven corneal imaging system that uses close-range raster photogrammetry to measure and produce a topographic map of the corneal surface. The CTS determines distortion in a projected two-dimensional grid. Unlike Placido-disc-based videokeratoscopes, the PAR CTS produces a true topographic map (elevation map) and requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. Because the system uses two noncoaxial optical paths, it can be integrated into other optical devices. A modified CTS was integrated into an experimental erbium: YAG photoablative laser. The CTS successfully imaged corneas before, after, and during laser photoablation. Its ability to image nonreflective surfaces and to be integrated into other optical systems may make it suitable for intraoperative refractive monitoring.

  19. Endophthalmitis following 27-Gauge Pars Plana Vitrectomy for Vitreous Floaters

    PubMed Central

    Lin, Zhong; Wu, Rong Han; Moonasar, Nived

    2016-01-01

    Purpose To report a case of Staphylococcus epidermidis endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. Methods The clinical course and imaging findings, including fundus optomap, and spectral domain optical coherence tomography of a 24-year-old male patient were documented. Results The patient, with a preoperative best-corrected visual acuity (BCVA) of 1.0, developed endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. After a series of treatments, including emergent vitreous tap and silicone oil injection, antibiotic treatment, and silicone oil removal, the patient regained a BCVA of 0.6. Conclusion Although rare, the potential risk of endophthalmitis should be explicitly discussed with patients considering surgical intervention for vitreous floaters. PMID:28101041

  20. Exploration of a new series of PAR1 antagonists.

    PubMed

    Planty, Bruno; Pujol, Chantal; Lamothe, Marie; Maraval, Catherine; Horn, Clemens; Le Grand, Bruno; Perez, Michel

    2010-03-01

    Two series of new PAR1 antagonists have been identified. The first incorporates a cinnamoylpiperidine motif and the second a cinnamoylpyridine pattern. The synthesis, biological activity and structure-activity relationship of these compounds are presented. In each series, one analog showed potent in vivo antithrombotic activity in a rat AV shunt model, with up to 53% inhibition at 1.25mpk iv for compound 30.

  1. Accuracy of the PAR corneal topography system with spatial misalignment.

    PubMed

    Belin, M W; Zloty, P

    1993-01-01

    The PAR Corneal Topography System is a computerized corneal imaging system which uses close-range raster photogrammetry to measure and produce a topographic map of the corneal surface. Raster photogrammetry is a standard method of extracting object information by projecting a known pattern onto an object and recording the distortion when viewed from an oblique angle. Unlike placido disc based videokeratoscopes, the PAR system requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. We studied both the accuracy of the system with purposeful misalignment (defocusing) of the test object and determined the ability to image freshly deepithelialized, keratectomized, and photoablated corneas. The PAR system was both accurate and reproducible in imaging calibrated spheres within a defined zone in space. Whole cadaver eyes were imaged both before and immediately after removal of the epithelium, lamellar keratectomy, and laser photoablation. The system demonstrated the ability to image irregular, deepithelialized, and keratectomized corneas. The ability to maintain accuracy without precise alignment and the facility to image freshly deepithelialized and keratectomized corneas may make the system suitable for intraoperative refractive monitoring.

  2. The Pars Interarticularis Stress Reaction, Spondylolysis, and Spondylolisthesis Progression

    PubMed Central

    Motley, Gina; Nyland, John; Jacobs, Jake; Caborn, David N. M.

    1998-01-01

    Objective: To review the classification, etiology, clinical and radiologic evaluation, and management of the pars interarticularis stress reaction, spondylolysis, and spondylolisthesis progression. Data Sources: Grateful Med was searched from 1980 to 1998 using the terms “spondylolysis,” “spondylolisthesis,” “female athlete” “spondylogenic,” and “pars interarticularis.” Data Synthesis: The progression from pars interarticularis stress reaction through spondylolysis to spondylolisthesis is common in adolescent athletes, and, because of hormonal influences and cheerleading and gymnastic maneuvers, females are particularly at risk. Proper diagnosis and management include a thorough evaluation, radiographs (possibly with technetium bone scan or single-photon emission computed tomography), activity modification, dietary counseling, a therapeutic exercise program focusing on proper trunk and hip muscle strength and extensibility balances, and education regarding proper back postures, positioning, lifting mechanics, and jump landings. Conclusions/Recommendations: The athletic trainer plays an integral part in managing this injury progression, particularly with identifying at-risk individuals and intervening appropriately. ImagesFigure 4. PMID:16558534

  3. La modélisation par Reverse Monte Carlo (RMC)

    NASA Astrophysics Data System (ADS)

    McGreevy, R. L.

    2003-09-01

    La technique de modélisation par Reverse Monte Carlo (RMC) est une méthode générale de modélisation structurale à partir d'un ensemble de données expérimentales. Cette méthode étant très souple, elle peut s'appliquer à de nombreux types de données. Jusqu'à présent ces applications comprennent : la diffraction des neutrons (y compris la substitution isotopique), la diffraction des rayons X (y compris la diffusion anomale), la diffraction des électrons, la RMN (les techniques d'angle magique et de 2ème moment) et l'EXAFS. Les systèmes étudiés sont également d'une grande variété : liquides, verres, polymères, cristaux et matériaux magnétiques, par exemple. Ce cours présente les bases de la méthode RMC en signalant certaines des idées fausses répandues. L'accent sera mis sur le fait que les modèles structuraux obtenus par RMC ne sont ni'uniques' ni 'exacts' ; cependant ils sont souvent utiles à la compréhension soit de la structure du système, soit des relations entre structure et autres propriétés physiques.

  4. Two cases of malignant glaucoma unresolved by pars plana vitrectomy

    PubMed Central

    Hosoda, Yoshikatsu; Akagi, Tadamichi; Yoshimura, Nagahisa

    2014-01-01

    Malignant glaucoma, which is characterized by a shallow or flat anterior chamber with high intraocular pressure, can usually be resolved by pars plana vitrectomy with anterior hyaloidectomy. We describe two cases in which malignant glaucoma was refractory to conventional treatment and complete vitrectomy. Case one an 88-year-old woman with pseudoexfoliation glaucoma underwent trabeculotomy and subsequently developed malignant glaucoma. Four months after transient recovery by pars plana vitrectomy, the malignant glaucoma recurred. She underwent peripheral iridectomy and local zonulectomy with successful control of her intraocular pressure. In case two, an 85-year-old man had a history of pseudoexfoliation glaucoma. Seven months after phacoemulsification and intraocular lens implantation, he developed malignant glaucoma that was refractory to pars plana vitrectomy. He underwent peripheral iridectomy, goniosynechialysis and trabectome surgery resulting in the successful control of his intraocular pressure. In rare cases of malignant glaucoma refractive to vitrectomy, peripheral iridectomy with or without local zonulectomy is a reasonable and minimally invasive surgical procedure. PMID:24729683

  5. ParB Partition Proteins: Complex Formation and Spreading at Bacterial and Plasmid Centromeres

    PubMed Central

    Funnell, Barbara E.

    2016-01-01

    In bacteria, active partition systems contribute to the faithful segregation of both chromosomes and low-copy-number plasmids. Each system depends on a site-specific DNA binding protein to recognize and assemble a partition complex at a centromere-like site, commonly called parS. Many plasmid, and all chromosomal centromere-binding proteins are dimeric helix-turn-helix DNA binding proteins, which are commonly named ParB. Although the overall sequence conservation among ParBs is not high, the proteins share similar domain and functional organization, and they assemble into similar higher-order complexes. In vivo, ParBs “spread,” that is, DNA binding extends away from the parS site into the surrounding non-specific DNA, a feature that reflects higher-order complex assembly. ParBs bridge and pair DNA at parS and non-specific DNA sites. ParB dimers interact with each other via flexible conformations of an N-terminal region. This review will focus on the properties of the HTH centromere-binding protein, in light of recent experimental evidence and models that are adding to our understanding of how these proteins assemble into large and dynamic partition complexes at and around their specific DNA sites. PMID:27622187

  6. Specific and non-specific interactions of ParB with DNA: implications for chromosome segregation

    PubMed Central

    Taylor, James A.; Pastrana, Cesar L.; Butterer, Annika; Pernstich, Christian; Gwynn, Emma J.; Sobott, Frank; Moreno-Herrero, Fernando; Dillingham, Mark S.

    2015-01-01

    The segregation of many bacterial chromosomes is dependent on the interactions of ParB proteins with centromere-like DNA sequences called parS that are located close to the origin of replication. In this work, we have investigated the binding of Bacillus subtilis ParB to DNA in vitro using a variety of biochemical and biophysical techniques. We observe tight and specific binding of a ParB homodimer to the parS sequence. Binding of ParB to non-specific DNA is more complex and displays apparent positive co-operativity that is associated with the formation of larger, poorly defined, nucleoprotein complexes. Experiments with magnetic tweezers demonstrate that non-specific binding leads to DNA condensation that is reversible by protein unbinding or force. The condensed DNA structure is not well ordered and we infer that it is formed by many looping interactions between neighbouring DNA segments. Consistent with this view, ParB is also able to stabilize writhe in single supercoiled DNA molecules and to bridge segments from two different DNA molecules in trans. The experiments provide no evidence for the promotion of non-specific DNA binding and/or condensation events by the presence of parS sequences. The implications of these observations for chromosome segregation are discussed. PMID:25572315

  7. Dynamic Filament Formation by a Divergent Bacterial Actin-Like ParM Protein

    PubMed Central

    Brzoska, Anthony J.; Jensen, Slade O.; Barton, Deborah A.; Davies, Danielle S.; Overall, Robyn L.; Skurray, Ronald A.; Firth, Neville

    2016-01-01

    Actin-like proteins (Alps) are a diverse family of proteins whose genes are abundant in the chromosomes and mobile genetic elements of many bacteria. The low-copy-number staphylococcal multiresistance plasmid pSK41 encodes ParM, an Alp involved in efficient plasmid partitioning. pSK41 ParM has previously been shown to form filaments in vitro that are structurally dissimilar to those formed by other bacterial Alps. The mechanistic implications of these differences are not known. In order to gain insights into the properties and behavior of the pSK41 ParM Alp in vivo, we reconstituted the parMRC system in the ectopic rod-shaped host, E. coli, which is larger and more genetically amenable than the native host, Staphylococcus aureus. Fluorescence microscopy showed a functional fusion protein, ParM-YFP, formed straight filaments in vivo when expressed in isolation. Strikingly, however, in the presence of ParR and parC, ParM-YFP adopted a dramatically different structure, instead forming axial curved filaments. Time-lapse imaging and selective photobleaching experiments revealed that, in the presence of all components of the parMRC system, ParM-YFP filaments were dynamic in nature. Finally, molecular dissection of the parMRC operon revealed that all components of the system are essential for the generation of dynamic filaments. PMID:27310470

  8. Developmental Control of a parAB Promoter Leads to Formation of Sporulation-Associated ParB Complexes in Streptomyces coelicolor

    PubMed Central

    Jakimowicz, Dagmara; Mouz, Sebastien; Zakrzewska-Czerwińska, Jolanta; Chater, Keith F.

    2006-01-01

    The Streptomyces coelicolor partitioning protein ParB binds to numerous parS sites in the oriC-proximal part of the linear chromosome. ParB binding results in the formation of large complexes, which behave differentially during the complex life cycle (D. Jakimowicz, B. Gust, J. Zakrzewska-Czerwinska, and K. F. Chater, J. Bacteriol. 187:3572-3580, 2005). Here we have analyzed the transcriptional regulation that underpins this developmentally specific behavior. Analysis of promoter mutations showed that the irregularly spaced complexes present in vegetative hyphae are dependent on the constitutive parABp1 promoter, while sporulation-specific induction of the promoter parABp2 is required for the assembly of arrays of ParB complexes in aerial hyphae and thus is necessary for efficient chromosome segregation. Expression from parABp2 depended absolutely on two sporulation regulatory genes, whiA and whiB, and partially on two others, whiH and whiI, all four of which are needed for sporulation septation. Because of this pattern of dependence, we investigated the transcription of these four whi genes in whiA and whiB mutants, revealing significant regulatory interplay between whiA and whiB. A strain in which sporulation septation (but not vegetative septation) was blocked by mutation of a sporulation-specific promoter of ftsZ showed close to wild-type induction of parABp2 and formed fairly regular ParB-enhanced green fluorescent protein foci in aerial hyphae, ruling out strong morphological coupling or checkpoint regulation between septation and DNA partitioning during sporulation. A model for developmental regulation of parABp2 expression is presented. PMID:16484182

  9. Caracterisation et transformation par hydroviscoreduction du brut lourd de Doba/Tchad: Strategie de pompage par pipeline

    NASA Astrophysics Data System (ADS)

    Dehkissia, Soumaine

    Le projet de la these est defini par rapport a la recente exploitation commerciale du brut lourd de Doba, une region du Tchad, pays enclave d'ou le brut ainsi produit doit etre achemine par pipeline. Le but dans ce travail est de caracteriser ce brut et de determiner une strategie thermique de transformation en vue de reduire de la facon la plus economique, la viscosite du brut pour permettre son transport par pipeline. Concernant la partie caracterisation, nous avons utilise entre autres, un rheometre rotatif et des analyseurs (LECO CHN-2000 & LECO S-144DR Elemental Analyzers) pour evaluer respectivement la viscosite et les elements tels que C, H, N, O, S. Sur la base des methodes de transformation disponibles, nous avons determine une strategie simple de transformation thermique par hydroviscoreduction , strategie dans laquelle, la fraction legere du brut comme le naphta (80--180°C), pourrait constituer la source d'hydrogene a utiliser. Le brut de Doba, a une faible teneur en soufre (0.14%) et sa densite specifique de 0.940 a 15.6°C, soit 18.8° API, le classe parmi les bruts lourds. Outre le point initial se situant a 85°C, la distillation du brut a revele que la fraction distillant avant 250°C ne represente que 10% (v/v) et que le craquage thermique du substrat debute a 300°C. Par ailleurs, outre son caractere Newtonien, les densites specifiques de la fraction lourde de l'essence (100--200°C) et de la fraction distillant au-dessus 350°C, etant respectivement de 0.813 (0.813 > 0.800) et de 0.951 (0.930 < 0.951 < 0.975), le brut de Doba est donc de type aromatique. Les viscosites du brut et du brut desasphalte, sont respectivement de 184.4 cSt et 152.4 cSt a 50°C, suggerant que le desasphaltage ne constitue pas une methode efficace pouvant aider au pompage du brut par pipeline, d'ou la necessite de transformation. Les resultats des travaux en autoclave montrent que, si le brut doit etre traite entierement, la viscosite de 25cSt 50°C, recommandee pour le

  10. ParABS Systems of the Four Replicons of Burkholderia cenocepacia: New Chromosome Centromeres Confer Partition Specificity†

    PubMed Central

    Dubarry, Nelly; Pasta, Franck; Lane, David

    2006-01-01

    Most bacterial chromosomes carry an analogue of the parABS systems that govern plasmid partition, but their role in chromosome partition is ambiguous. parABS systems might be particularly important for orderly segregation of multipartite genomes, where their role may thus be easier to evaluate. We have characterized parABS systems in Burkholderia cenocepacia, whose genome comprises three chromosomes and one low-copy-number plasmid. A single parAB locus and a set of ParB-binding (parS) centromere sites are located near the origin of each replicon. ParA and ParB of the longest chromosome are phylogenetically similar to analogues in other multichromosome and monochromosome bacteria but are distinct from those of smaller chromosomes. The latter form subgroups that correspond to the taxa of their hosts, indicating evolution from plasmids. The parS sites on the smaller chromosomes and the plasmid are similar to the “universal” parS of the main chromosome but with a sequence specific to their replicon. In an Escherichia coli plasmid stabilization test, each parAB exhibits partition activity only with the parS of its own replicon. Hence, parABS function is based on the independent partition of individual chromosomes rather than on a single communal system or network of interacting systems. Stabilization by the smaller chromosome and plasmid systems was enhanced by mutation of parS sites and a promoter internal to their parAB operons, suggesting autoregulatory mechanisms. The small chromosome ParBs were found to silence transcription, a property relevant to autoregulation. PMID:16452432

  11. Is PAR a Good Investment? Understanding the Costs and Benefits of Teacher Peer Assistance and Review Programs

    ERIC Educational Resources Information Center

    Papay, John P.; Johnson, Susan Moore

    2012-01-01

    Peer Assistance and Review (PAR) is a local labor-management initiative designed to improve teacher quality. In PAR, expert "consulting teachers" mentor, support, and evaluate novice and underperforming veteran teachers. Evaluations under PAR can lead to dismissals. The authors examine the costs and benefits of PAR, both financial and…

  12. Structures of actin-like ParM filaments show architecture of plasmid-segregating spindles.

    PubMed

    Bharat, Tanmay A M; Murshudov, Garib N; Sachse, Carsten; Löwe, Jan

    2015-07-02

    Active segregation of Escherichia coli low-copy-number plasmid R1 involves formation of a bipolar spindle made of left-handed double-helical actin-like ParM filaments. ParR links the filaments with centromeric parC plasmid DNA, while facilitating the addition of subunits to ParM filaments. Growing ParMRC spindles push sister plasmids to the cell poles. Here, using modern electron cryomicroscopy methods, we investigate the structures and arrangements of ParM filaments in vitro and in cells, revealing at near-atomic resolution how subunits and filaments come together to produce the simplest known mitotic machinery. To understand the mechanism of dynamic instability, we determine structures of ParM filaments in different nucleotide states. The structure of filaments bound to the ATP analogue AMPPNP is determined at 4.3 Å resolution and refined. The ParM filament structure shows strong longitudinal interfaces and weaker lateral interactions. Also using electron cryomicroscopy, we reconstruct ParM doublets forming antiparallel spindles. Finally, with whole-cell electron cryotomography, we show that doublets are abundant in bacterial cells containing low-copy-number plasmids with the ParMRC locus, leading to an asynchronous model of R1 plasmid segregation.

  13. Urokinase type plasminogen activator receptor (uPAR) as a new therapeutic target in cancer

    PubMed Central

    Montuori, Nunzia; Pesapane, Ada; Rossi, Francesca W; Giudice, Valentina; De Paulis, Amato; Selleri, Carmine; Ragno, Pia

    2016-01-01

    The urokinase (uPA)-type plasminogen activator receptor (uPAR) is a GPI-anchored receptor that focuses urokinase (uPA) proteolytic activity on the cell surface. uPAR also regulates cell adhesion, migration and proliferation, protects from apoptosis and contributes to epithelial mesenchymal transition (EMT), independently of uPA enzymatic activity. Indeed, uPAR interacts with beta1, beta2 and beta3 integrins, thus regulating their activities. uPAR cross-talks with receptor tyrosine kinases through integrins and regulates cancer cell dormancy, proliferation and angiogenesis. Moreover, uPAR mediates uPA-dependent cell migration and chemotaxis induced by fMet-Leu-Phe (fMLF), through its association with fMLF-receptors (fMLF-Rs). Further, uPAR is an adhesion receptor because it binds vitronectin (VN), a component of provisional extracellular matrix. High uPAR expression predicts for more aggressive disease in several cancer types for its ability to increase invasion and metastasis. In fact, uPAR has been hypothesized to be the link between tumor cell dormancy and proliferation that usually precedes the onset of metastasis. Thus, inhibiting uPAR could be a feasible approach to affect tumor growth and metastasis. Here, we review the more recent advances in the development of uPAR-targeted anti-cancer therapeutic agents suitable for further optimization or ready for the evaluation in early clinical trials. PMID:27896223

  14. A model for the condensation of the bacterial chromosome by the partitioning protein ParB

    NASA Astrophysics Data System (ADS)

    Broedersz, Chase; Wingreen, Ned

    2013-03-01

    The molecular machinery responsible for faithful segregation of the chromosome in bacteria such as Caulobacter crescentus and Bacillus subtilis includes the ParABS a.k.a. Spo0J/Soj partitioning system. In Caulobacter, prior to division, hundreds of ParB proteins bind to the DNA near the origin of replication, and localize to one pole of the cell. Subsequently, the ParB-DNA complex is translocated to the far pole by the binding and retraction of the ParA spindle-like apparatus. Remarkably, the localization of ParB proteins to specific regions of the chromosome appears to be controlled by only a few centromeric parS binding sites. Although lateral interactions between DNA-bound ParB are likely to be important for their localization, the long-range order of ParB domains on the chromosome appears to be inconsistent with a picture in which protein-protein interactions are limited to neighboring DNA-bound proteins. We developed a coarse-grained Brownian dynamics model that allows for lateral and 3D protein-protein interactions among bound ParB proteins. Our model shows how such interactions can condense and organize the DNA spatially, and can control the localization and the long-range order of the DNA-bound proteins.

  15. PAR-2 expression in the gingival crevicular fluid reflects chronic periodontitis severity.

    PubMed

    Fukushima, Henrique; Alves, Vanessa Tubero Euzebio; Carvalho, Verônica Franco de; Ambrósio, Lucas Macedo Batitucci; Eichler, Rosangela Aparecida Dos Santos; Carvalho, Maria Helena Catelli de; Saraiva, Luciana; Holzhausen, Marinella

    2017-01-26

    Recent studies investigating protease-activated receptor type 2 (PAR-2) suggest an association between the receptor and periodontal inflammation. It is known that gingipain, a bacterial protease secreted by the important periodontopathogen Porphyromonas gingivalis can activate PAR-2. Previous studies by our group found that PAR-2 is overexpressed in the gingival crevicular fluid (GCF) of patients with moderate chronic periodontitis (MP). The present study aimed at evaluating whether PAR-2 expression is associated with chronic periodontitis severity. GCF samples and clinical parameters, including plaque and bleeding on probing indices, probing pocket depth and clinical attachment level, were collected from the control group (n = 19) at baseline, and from MP patients (n = 19) and severe chronic periodontitis (SP) (n = 19) patients before and 6 weeks after periodontal non-surgical treatment. PAR-2 and gingipain messenger RNA (mRNA) in the GCF of 4 periodontal sites per patient were evaluated by Reverse Transcription Polymerase Chain Reaction (RT-qPCR). PAR-2 and gingipain expressions were greater in periodontitis patients than in control group patients. In addition, the SP group presented increased PAR-2 and gingipain mRNA levels, compared with the MP group. Furthermore, periodontal treatment significantly reduced (p <0.05) PAR-2 expression in patients with periodontitis. In conclusion, PAR-2 is associated with chronic periodontitis severity and with gingipain levels in the periodontal pocket, thus suggesting that PAR-2 expression in the GCF reflects the severity of destruction during periodontal infection.

  16. PAR-1 contributes to the innate immune response during viral infection

    PubMed Central

    Antoniak, Silvio; Owens, A. Phillip; Baunacke, Martin; Williams, Julie C.; Lee, Rebecca D.; Weithäuser, Alice; Sheridan, Patricia A.; Malz, Ronny; Luyendyk, James P.; Esserman, Denise A.; Trejo, JoAnn; Kirchhofer, Daniel; Blaxall, Burns C.; Pawlinski, Rafal; Beck, Melinda A.; Rauch, Ursula; Mackman, Nigel

    2013-01-01

    Coagulation is a host defense system that limits the spread of pathogens. Coagulation proteases, such as thrombin, also activate cells by cleaving PARs. In this study, we analyzed the role of PAR-1 in coxsackievirus B3–induced (CVB3-induced) myocarditis and influenza A infection. CVB3-infected Par1–/– mice expressed reduced levels of IFN-β and CXCL10 during the early phase of infection compared with Par1+/+ mice that resulted in higher viral loads and cardiac injury at day 8 after infection. Inhibition of either tissue factor or thrombin in WT mice also significantly increased CVB3 levels in the heart and cardiac injury compared with controls. BM transplantation experiments demonstrated that PAR-1 in nonhematopoietic cells protected mice from CVB3 infection. Transgenic mice overexpressing PAR-1 in cardiomyocytes had reduced CVB3-induced myocarditis. We found that cooperative signaling between PAR-1 and TLR3 in mouse cardiac fibroblasts enhanced activation of p38 and induction of IFN-β and CXCL10 expression. Par1–/– mice also had decreased CXCL10 expression and increased viral levels in the lung after influenza A infection compared with Par1+/+ mice. Our results indicate that the tissue factor/thrombin/PAR-1 pathway enhances IFN-β expression and contributes to the innate immune response during single-stranded RNA viral infection. PMID:23391721

  17. Microscopie en champ proche par réflexion

    NASA Astrophysics Data System (ADS)

    Spajer, M.; Courjon, D.; Sarayeddine, K.; Jalocha, A.; Vigoureux, J.-M.

    1991-01-01

    This communication presents two techniques for high resolution surface analysis. In the first one, the illumination beam is totally reflected under the object surface, which must be transparent. The evanescent wave confined on the surface is frustrated locally by a dielectric probe of nanometric dimension which scans the objetc. A horizontal resolution of 10 nm and a vertical one of 1 nm have been obtained. In the second one, more adapted to metallic objects, the surface is illuminated by the near-field of the stylus, in which the reflected beam is Partially launched. First results dealing with the characterization of the dielectric stylus are presented. Cette communication présente deux techniques permettant l'analyse de surface haute résolution. Dans la première, le faisceau d'éclairage est réfléchi totalement sous la surface de l'objet, nécessairement transparent. L'onde évanescente qui l'accompagne est frustrée localement par une pointe diélectrique de dimension nanométrique balayant la surface. Une résolution de 10 nm horizontalement et de 1nm verticalement a été obtenue. Dans la seconde, qui permet d'étudier un objet opaque, celui-ci est éclairé par le champ proche émis par la pointe, dans laquelle le faisceau réfléchi est partiellement réinjecté. Les premiers résultats concernant la caractérisation de la pointe sont présentés.

  18. [Relationships of rice canopy PAR interception and light use efficiency to grain yield].

    PubMed

    Tang, Liang; Zhu, Xiang-Cheng; Cao, Meng-Ying; Cao, Wei-Xing; Zhu, Yan

    2012-05-01

    Taking two rice cultivars (Liangyoupeijiu and Wuxiangjing 14) with different plant types as test materials, a 2-year field experiment was conducted to study the relationships of rice canopy photosynthetically active radiation (PAR) interception and light use efficiency to grain yield under three planting densities and five nitrogen (N) application rates. From tillering to maturing stage, the average PAR reflectance in all treatments was 3.45%. The ratio of reflected PAR to the total loss of PAR from tillering to heading stage was 10.90%, which was significantly lower than that (22.06%) from heading to maturiting stage. The PAR conversion efficiency from tillering to maturing stage decreased with increasing planting density but increased with increasing nitrogen rate, and the conversion efficiency was significantly higher from tillering to heading than from heading to maturing stage. The PAR use efficiency from tillering to maturing stage increased with the increase of planting density and nitrogen application rate, and the average PAR use efficiency of Liangyoupeijiu (1.83 g x MJ(-1)) was significantly higher than that of Wuxiangjing 14 (1.42 g x MJ(-1)). Due to the longer growth period of Wuxiangjing 14, its incident PAR and intercepted PAR under midium and high planting densities were higher, as compared with Liangyoupeijiu. The grain yield was significantly positively correlated with the canopy PAR interceptance and use efficiency at different growth stages, but less correlated with the PAR conversion efficiency. To increase the canopy PAR use efficiency and conversion efficiency on the basis of maintaining higher PAR interception rate could be an effective way to increase rice yield.

  19. PAR1 is selectively over expressed in high grade breast cancer patients: a cohort study

    PubMed Central

    Hernández, Norma A; Correa, Elma; Avila, Esther P; Vela, Teresa A; Pérez, Víctor M

    2009-01-01

    Background The protease-activated receptor (PAR1) expression is correlated with the degree of invasiveness in cell lines. Nevertheless it has never been directed involved in breast cancer patients progression. The aim of this study was to determine whether PAR1 expression could be used as predictor of metastases and mortality. Methods In a cohort of patients with infiltrating ductal carcinoma studied longitudinally since 1996 and until 2007, PAR1 over-expression was assessed by immunoblotting, immunohistochemistry, and flow citometry. Chi-square and log rank tests were used to determine whether there was a statistical association between PAR1 overexpression and metastases, mortality, and survival. Multivariate analysis was performed including HER1, stage, ER and nodes status to evaluate PAR1 as an independent prognostic factor. Results Follow up was 95 months (range: 2–130 months). We assayed PAR1 in a cohort of patients composed of 136 patients; we found PAR1 expression assayed by immunoblotting was selectively associated with high grade patients (50 cases of the study cohort; P = 0.001). Twenty-nine of 50 (58%) patients overexpressed PAR1, and 23 of these (46%) developed metastases. HER1, stage, ER and PAR1 overexpression were robustly correlated (Cox regression, P = 0.002, P = 0.024 and P = 0.002 respectively). Twenty-one of the 50 patients (42%) expressed both receptors (PAR1 and HER1 P = 0.0004). We also found a statistically significant correlation between PAR1 overexpression and increased mortality (P = 0.0001) and development of metastases (P = 0.0009). Conclusion Our data suggest PAR1 overexpression may be involved in the development of metastases in breast cancer patient and is associated with undifferentiated cellular progression of the tumor. Further studies are needed to understand PAR1 mechanism of action and in a near future assay its potential use as risk factor for metastasis development in high grade breast cancer patients. PMID:19538737

  20. Recalculation of shielding for the addition of a PAR

    SciTech Connect

    Moe, H.J.

    1988-08-01

    The shielding estimates for the Electron and Positron Linacs and the Booster Synchrotron, contained in the 1987 Conceptual Design Report (CDR) of the APS (ANL-87-15), have been reviewed and recalculated, along with newly initiated calculations of the required shielding for the addition of a Positron Accumulator Ring (PAR). Several new assumptions with respect to beam intensity, projected losses in the system, and assumed operational time have been incorporated into the calculations. Details of the previous calculations, which describe the methodology used, may be found in APS Light Source Note LS-90.

  1. BOREAS TE-12 Incoming PAR Through the Forest Canopy Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Walter-Shea, Elizabeth A.; Mesarch, Mark A.

    2000-01-01

    The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-12 (Terrestrial Ecology) team collected photosynthetically active radiation (PAR) data sets in support of its efforts to characterize and interpret information on shoot geometry, leaf optical properties, leaf water potential, and leaf gas exchange. The data were collected at the Southern Study Area-Old Black Spruce (SSA-OBS) site from 04-Jul-1996 to 25-Jul-1996. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  2. A systematic computation scheme of PAR-WIG cruising performance

    NASA Astrophysics Data System (ADS)

    Ando, Shigenori

    1993-08-01

    A systematic computation scheme is presented for PAR-WIG cruising performance, on a FORTRAN program. It is suitable for implementation on PCs. Effects of many parameters on the transportation efficiency are explored. Two concepts are presented in three views and artist impressions. One is a smallest single-crewman vehicle for experiment, sports, or pleasure. The other is a large vehicle for civil transportation. Both have twin hulls, which are quite suitable for installing a 'SMALL-TAIL-WIG' or 'WIG-let' to establish longitudinal attitude stability.

  3. David Kasner, MD, and the Road to Pars Plana Vitrectomy

    PubMed Central

    Blodi, Christopher F.

    2016-01-01

    David Kasner, MD (1927–2001), used his extensive dissections of eye bank eyes and experiences in teaching cataract surgery to resident physicians to realize that excision of vitreous when present in the anterior chamber of eyes undergoing cataract surgery was preferable to prior intraoperative procedures. Noting that eyes tolerated his maneuvers, he then performed planned subtotal open-sky vitrectomies; first on a traumatized eye in 1961, then on two eyes of patients with amyloidosis (1966–1967). The success of these operations was noted by others, most particularly Robert Machemer, MD. Kasner’s work directly led to further surgical developments, including closed pars plana vitrectomy. PMID:27660504

  4. Mutations in the gyrB, parC, and parE genes of quinolone-resistant isolates and mutants of Edwardsiella tarda.

    PubMed

    Kim, Myoung Sug; Jun, Lyu Jin; Shin, Soon Bum; Park, Myoung Ae; Jung, Sung Hee; Kim, Kwangil; Moon, Kyung Ho; Jeong, Hyun Do

    2010-12-01

    The full length genes gyrB (2,415 bp), parC (2,277 bp), and parE (1,896 bp) in Edwardsiella tarda were cloned by PCR with degenerate primers based on the sequence of the respective quinolone resistance-determining region (QRDR), followed by elongation of 5' and 3' ends using cassette ligation-mediated PCR (CLMP). Analysis of the cloned genes revealed open reading frames (ORFs) encoding proteins of 804 (GyrB), 758 (ParC), and 631 (ParE) amino acids with conserved gyrase/topoisomerase features and motifs important for enzymatic function. The ORFs were preceded by putative promoters, ribosome binding sites, and inverted repeats with the potential to form cruciform structures for binding of DNA-binding proteins. When comparing the deduced amino acid sequences of E. tarda GyrB, ParC, and ParE with those of the corresponding proteins in other bacteria, they were found to be most closely related to Escherichia coli GyrB (87.6% identity), Klebsiella pneumoniae ParC (78.8% identity) and Salmonella typhimurium ParE (89.5% identity), respectively. The two topoisomerase genes, parC and parE, were found to be contiguous on the E. tarda chromosome. All 18 quinoloneresistant isolates obtained from Korea thus far did not contain subunit alternations apart from a substitution in GyrA (Ser83→Arg). However, an alteration in the QRDR of ParC (Ser84→Ile) following an amino acid substitution in GyrA (Asp87→Gly) was detected in E. tarda mutants selected in vitro at 8 microng/ml ciprofloxacin (CIP). A mutant with a GyrB (Ser464→Leu) and GyrA (Asp87→Gly) substitution did not show a significant increase in the minimum inhibitory concentration (MIC) of CIP. None of the in vitro mutants exhibited mutations in parE. Thus, gyrA and parC should be considered to be the primary and secondary targets, respectively, of quinolones in E. tarda.

  5. Estimating Photosynthetically Available Radiation (PAR) at the Earth's surface from satellite observations

    NASA Technical Reports Server (NTRS)

    Frouin, Robert

    1993-01-01

    Current satellite algorithms to estimate photosynthetically available radiation (PAR) at the earth' s surface are reviewed. PAR is deduced either from an insolation estimate or obtained directly from top-of-atmosphere solar radiances. The characteristics of both approaches are contrasted and typical results are presented. The inaccuracies reported, about 10 percent and 6 percent on daily and monthly time scales, respectively, are useful to model oceanic and terrestrial primary productivity. At those time scales variability due to clouds in the ratio of PAR and insolation is reduced, making it possible to deduce PAR directly from insolation climatologies (satellite or other) that are currently available or being produced. Improvements, however, are needed in conditions of broken cloudiness and over ice/snow. If not addressed properly, calibration/validation issues may prevent quantitative use of the PAR estimates in studies of climatic change. The prospects are good for an accurate, long-term climatology of PAR over the globe.

  6. The Par3 polarity protein is an exocyst receptor essential for mammary cell survival

    PubMed Central

    Ahmed, Syed Mukhtar; Macara, Ian G.

    2017-01-01

    The exocyst is an essential component of the secretory pathway required for delivery of basolateral proteins to the plasma membranes of epithelial cells. Delivery occurs adjacent to tight junctions (TJ), suggesting that it recognizes a receptor at this location. However, no such receptor has been identified. The Par3 polarity protein associates with TJs but has no known function in membrane traffic. We now show that, unexpectedly, Par3 is essential for mammary cell survival. Par3 silencing causes apoptosis, triggered by phosphoinositide trisphosphate depletion and decreased Akt phosphorylation, resulting from failure of the exocyst to deliver basolateral proteins to the cortex. A small region of PAR3 binds directly to Exo70 and is sufficient for exocyst docking, membrane-protein delivery and cell survival. PAR3 lacking this domain can associate with the cortex but cannot support exocyst function. We conclude that Par3 is the long-sought exocyst receptor required for targeted membrane-protein delivery. PMID:28358000

  7. Brulure par Foudre. A Propos d’une Observation

    PubMed Central

    Mradmi, W.; Fassi-Fihri, J.; Mehaji, G.; Ezzoubi, M.; Diouri, M.; Bahechar, N.; Boukind, E.H.

    2005-01-01

    Summary Aussi loin que l’on remonte dans la littérature, on retrouve des récits relatant des accidents consécutifs à la fulguration chez l’homme. La foudre était alors associée à la colère des dieux ou à la notion de châtiment. La fulguration correspond à un transfert d’énergie entre un cumulonimbus de charge négative et un objet de charge positive se trouvant au niveau du sol. Les lésions déterminées sont à la fois thermiques et électrothermiques. Bien que l’arrêt cardiorespiratoire soit une cause bien documentée de décès, la plupart des cas rapportés dans la littérature décrivent un éventail très disparate des séquelles qui surviennent suite à cet accident. Les Auteurs rapportent le cas d’un patient atteint par la foudre en insistant particulièrement sur les complications neurologiques qui sont survenues en cours d’évolution. Se basant sur cette observation et sur une revue de la littérature, les Auteurs soulignent que le pronostic des patients atteints par la foudre est plus favorable que généralement rapporté. PMID:21990993

  8. Fluoroquinolone Resistance Mutations in the parC, parE, and gyrA Genes of Clinical Isolates of Viridans Group Streptococci

    PubMed Central

    González, Irene; Georgiou, Marios; Alcaide, Fernando; Balas, Delia; Liñares, Josefina; de la Campa, Adela G.

    1998-01-01

    The nucleotide sequences of the quinolone resistance-determining regions (QRDRs) of the parC and gyrA genes from seven ciprofloxacin-resistant (Cpr) isolates of viridans group streptococci (two high-level Cpr Streptococcus oralis and five low-level Cpr Streptococcus mitis isolates) were determined and compared with those obtained from susceptible isolates. The nucleotide sequences of the QRDRs of the parE and gyrB genes from the five low-level Cpr S. mitis isolates and from the NCTC 12261 type strain were also analyzed. Four of these low-level Cpr isolates had changes affecting the subunits of DNA topoisomerase IV: three in Ser-79 (to Phe or Ile) of ParC and one in ParE at a position not previously described to be involved in quinolone resistance (Pro-424). One isolate did not show any mutation. The two high-level Cpr S. oralis isolates showed mutations affecting equivalent residue positions of ParC and GyrA, namely, Ser-79 to Phe and Ser-81 to Phe or Tyr, respectively. The parC mutations were able to transform Streptococcus pneumoniae to ciprofloxacin resistance, while the gyrA mutations transformed S. pneumoniae only when mutations in parC were present. These results suggest that DNA topoisomerase IV is a primary target of ciprofloxacin in viridans group streptococci, DNA gyrase being a secondary target. PMID:9797205

  9. The PARA-suite: PAR-CLIP specific sequence read simulation and processing

    PubMed Central

    Kloetgen, Andreas; Borkhardt, Arndt; Hoell, Jessica I.

    2016-01-01

    Background Next-generation sequencing technologies have profoundly impacted biology over recent years. Experimental protocols, such as photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation (PAR-CLIP), which identifies protein–RNA interactions on a genome-wide scale, commonly employ deep sequencing. With PAR-CLIP, the incorporation of photoactivatable nucleosides into nascent transcripts leads to high rates of specific nucleotide conversions during reverse transcription. So far, the specific properties of PAR-CLIP-derived sequencing reads have not been assessed in depth. Methods We here compared PAR-CLIP sequencing reads to regular transcriptome sequencing reads (RNA-Seq) to identify distinctive properties that are relevant for reference-based read alignment of PAR-CLIP datasets. We developed a set of freely available tools for PAR-CLIP data analysis, called the PAR-CLIP analyzer suite (PARA-suite). The PARA-suite includes error model inference, PAR-CLIP read simulation based on PAR-CLIP specific properties, a full read alignment pipeline with a modified Burrows–Wheeler Aligner algorithm and CLIP read clustering for binding site detection. Results We show that differences in the error profiles of PAR-CLIP reads relative to regular transcriptome sequencing reads (RNA-Seq) make a distinct processing advantageous. We examine the alignment accuracy of commonly applied read aligners on 10 simulated PAR-CLIP datasets using different parameter settings and identified the most accurate setup among those read aligners. We demonstrate the performance of the PARA-suite in conjunction with different binding site detection algorithms on several real PAR-CLIP and HITS-CLIP datasets. Our processing pipeline allowed the improvement of both alignment and binding site detection accuracy. Availability The PARA-suite toolkit and the PARA-suite aligner are available at https://github.com/akloetgen/PARA-suite and https

  10. Participation of the urokinase-type plasminogen activator receptor (uPAR) in neutrophil transendothelial migration.

    PubMed

    Pliyev, Boris K; Antonova, Olga A; Menshikov, Mikhail

    2011-05-01

    The mechanisms underlying migration of neutrophils across endothelium are not completely understood. The urokinase-type plasminogen activator receptor (uPAR) plays a key role in neutrophil adhesion and migration. In the present study, we addressed whether uPAR regulates neutrophil transendothelial migration. We first showed that siRNA-mediated knockdown of uPAR in human umbilical vein endothelial cells (HUVECs) did not affect neutrophil migration across HUVEC monolayers indicating that endothelial uPAR does not regulate neutrophil transmigration. In contrast, the transmigration was significantly inhibited by Fab' fragment of anti-uPAR monoclonal antibody and proteolytically inactive urokinase (uPA), whereas inhibition of proteolytical activity of endogenous uPA (with amiloride or plasminogen activator inhibitor-1) did not affect the transmigration. Both the anti-uPAR Fab' fragment and proteolytically inactive uPA did not exert significant effects upon the transmigration conducted in the presence of F(ab')(2) fragment of blocking antibody to integrin Mac-1 indicating that uPAR regulates Mac-1-dependent transmigration. Mac-1-dependent, but not Mac-1-independent, transmigration was significantly reduced in the presence of N-acetyl-d-glucosamine and d-mannose, the saccharides that disrupt uPAR/Mac-1 association, but was unaffected in the presence of control saccharides (d-sorbitol and sucrose). We conclude that physical association of uPAR with Mac-1 mediates the regulatory effect of uPAR over the transmigration. Finally, we provide evidence that the functional cooperation between uPAR and Mac-1 is essential at both adhesion and diapedesis steps of neutrophil migration across endothelium. Thus, uPAR expressed on neutrophil plasma membrane regulates transendothelial migration independently of uPA proteolytical activity and acting as a cofactor for integrin Mac-1.

  11. Cancer-Selective Apoptotic Effects of Extracellular and Intracellular Par-4

    PubMed Central

    Bhattarai, Tripti Shrestha; Rangnekar, Vivek M.

    2010-01-01

    Selectivity toward cancer cells is the most desirable element in cancer therapeutics. Par-4 is a cancer cell-selective pro-apoptotic protein that functions intracellularly in the cytoplasmic and nuclear compartments, as a tumor suppressor. Moreover, recent findings indicate that the Par-4 protein is secreted by cells, and extracellular Par-4 induces cancer cell-specific apoptosis by interaction with the cell-surface receptor GRP78. This review describes the mechanisms underlying the apoptotic effects of both extracellular and intracellular Par-4 acting via its effector domain SAC. PMID:20440265

  12. Tryptase - PAR2 axis in Experimental Autoimmune Prostatitis, a model for Chronic Pelvic Pain Syndrome

    PubMed Central

    Roman, Kenny; Done, Joseph D.; Schaeffer, Anthony J.; Murphy, Stephen F.; Thumbikat, Praveen

    2014-01-01

    Chronic prostatitis/Chronic pelvic pain syndrome (CP/CPPS) affects up to 15% of the male population and is characterized by pelvic pain. Mast cells are implicated in the murine experimental autoimmune prostatitis (EAP) model as key to chronic pelvic pain development. The mast cell mediator tryptase-β and its cognate receptor protease-activated receptor 2 (PAR2) are involved in mediating pain in other visceral disease models. Prostatic secretions and urines from CP/CPPS patients were examined for the presence of mast cell degranulation products. Tryptase-β and PAR2 expression were examined in murine experimental autoimmune prostatitis (EAP). Pelvic pain and inflammation were assessed in the presence or absence of PAR2 expression and upon PAR2 neutralization. Tryptase-β and carboxypeptidase A3 were elevated in CP/CPPS compared to healthy volunteers. Tryptase-β was capable of inducing pelvic pain and was increased in EAP along with its receptor PAR2. PAR2 was required for the development of chronic pelvic pain in EAP. PAR2 signaling in dorsal root ganglia lead to ERK1/2 phosphorylation and calcium influx. PAR2 neutralization using antibodies attenuated chronic pelvic pain in EAP. The tryptase-PAR2 axis is an important mediator of pelvic pain in EAP and may play a role in the pathogenesis of CP/CPPS. PMID:24726923

  13. A Desired PAR-Achieving Precoder Design for Multiuser MIMO OFDM Based on Concentration of Measure

    NASA Astrophysics Data System (ADS)

    Cha, Hyun-Su; Kim, Dong Ku

    2017-03-01

    For multi-user multiple-input and multiple-output (MIMO) wireless communications in orthogonal frequency di- vision multiplexing systems, we propose a MIMO precoding scheme providing a desired peak-to-average power ratio (PAR) at the minimum cost that is defined as received SNR degradation. By taking advantage of the concentration of measure, we formulate a convex problem with constraint on the desired PAR. Consequently, the proposed scheme almost exactly achieves the desired PAR on average, and asymptotically attains the desired PAR at the 0.001 point of its complementary cumulative distribution function, as the number of subcarriers increases.

  14. TRIM21 is a novel regulator of Par-4 in colon and pancreatic cancer cells

    PubMed Central

    Nguyen, Jeffrey Q.; Irby, Rosalyn B.

    2017-01-01

    ABSTRACT The prostate apoptosis response protein 4 (Par-4) is a tumor-suppressor that has been shown to induce cancer-cell selective apoptosis in a variety of cancers. The regulation of Par-4 expression and activity is a relatively understudied area, and identifying novel regulators of Par-4 may serve as novel therapeutic targets. To identify novel regulators of Par-4, a co-immunoprecipitation was performed in colon cancer cells, and co-precipitated proteins were identified by mass-spectometry. TRIM21 was identified as a novel interacting partner of Par-4, and further shown to interact with Par-4 endogenously and through its PRY-SPRY domain. Additional studies show that TRIM21 downregulates Par-4 levels in response to cisplatin, and that TRIM21 can increase the resistance of colon cancer cells to cisplatin. Furthermore, forced Par-4 expression can sensitize pancreatic cancer cells to cisplatin. Finally, we demonstrate that TRIM21 expression predicts survival in pancreatic cancer patients. Our work highlights a novel mechanism of Par-4 regulation, and identifies a novel prognostic marker and potential therapeutic target for pancreatic cancer. PMID:27830973

  15. Tryptase-PAR2 axis in experimental autoimmune prostatitis, a model for chronic pelvic pain syndrome.

    PubMed

    Roman, Kenny; Done, Joseph D; Schaeffer, Anthony J; Murphy, Stephen F; Thumbikat, Praveen

    2014-07-01

    Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) affects up to 15% of the male population and is characterized by pelvic pain. Mast cells are implicated in the murine experimental autoimmune prostatitis (EAP) model as key to chronic pelvic pain development. The mast cell mediator tryptase-β and its cognate receptor protease-activated receptor 2 (PAR2) are involved in mediating pain in other visceral disease models. Prostatic secretions and urines from CP/CPPS patients were examined for the presence of mast cell degranulation products. Tryptase-β and PAR2 expression were examined in murine EAP. Pelvic pain and inflammation were assessed in the presence or absence of PAR2 expression and upon PAR2 neutralization. Tryptase-β and carboxypeptidase A3 were elevated in CP/CPPS compared to healthy volunteers. Tryptase-β was capable of inducing pelvic pain and was increased in EAP along with its receptor PAR2. PAR2 was required for the development of chronic pelvic pain in EAP. PAR2 signaling in dorsal root ganglia led to extracellular signal-regulated kinase (ERK)1/2 phosphorylation and calcium influx. PAR2 neutralization using antibodies attenuated chronic pelvic pain in EAP. The tryptase-PAR2 axis is an important mediator of pelvic pain in EAP and may play a role in the pathogenesis of CP/CPPS.

  16. The polarity protein Par3 regulates APP trafficking and processing through the endocytic adaptor protein Numb.

    PubMed

    Sun, Miao; Asghar, Suwaiba Z; Zhang, Huaye

    2016-09-01

    The processing of amyloid precursor protein (APP) into β-amyloid peptide (Aβ) is a key step in the pathogenesis of Alzheimer's disease (AD), and trafficking dysregulations of APP and its secretases contribute significantly to altered APP processing. Here we show that the cell polarity protein Par3 plays an important role in APP processing and trafficking. We found that the expression of full length Par3 is significantly decreased in AD patients. Overexpression of Par3 promotes non-amyloidogenic APP processing, while depletion of Par3 induces intracellular accumulation of Aβ. We further show that Par3 functions by regulating APP trafficking. Loss of Par3 decreases surface expression of APP by targeting APP to the late endosome/lysosome pathway. Finally, we show that the effects of Par3 are mediated through the endocytic adaptor protein Numb, and Par3 functions by interfering with the interaction between Numb and APP. Together, our studies show a novel role for Par3 in regulating APP processing and trafficking.

  17. Common variants in the human platelet PAR4 thrombin receptor alter platelet function and differ by race

    PubMed Central

    Edelstein, Leonard C.; Simon, Lukas M.; Lindsay, Cory R.; Kong, Xianguo; Teruel-Montoya, Raúl; Tourdot, Benjamin E.; Chen, Edward S.; Ma, Lin; Coughlin, Shaun; Nieman, Marvin; Holinstat, Michael; Shaw, Chad A.

    2014-01-01

    Human platelets express 2 thrombin receptors: protease-activated receptor (PAR)-1 and PAR4. Recently, we reported 3.7-fold increased PAR4-mediated aggregation kinetics in platelets from black subjects compared with white subjects. We now show that platelets from blacks (n = 70) express 14% more PAR4 protein than those from whites (n = 84), but this difference is not associated with platelet PAR4 function. Quantitative trait locus analysis identified 3 common single nucleotide polymorphisms in the PAR4 gene (F2RL3) associated with PAR4-induced platelet aggregation. Among these single nucleotide polymorphisms, rs773902 determines whether residue 120 in transmembrane domain 2 is an alanine (Ala) or threonine (Thr). Compared with the Ala120 variant, Thr120 was more common in black subjects than in white subjects (63% vs 19%), was associated with higher PAR4-induced human platelet aggregation and Ca2+ flux, and generated greater inositol 1,4,5-triphosphate in transfected cells. A second, less frequent F2RL3 variant, Phe296Val, was only observed in blacks and abolished the enhanced PAR4-induced platelet aggregation and 1,4,5-triphosphate generation associated with PAR4-Thr120. PAR4 genotype did not affect vorapaxar inhibition of platelet PAR1 function, but a strong pharmacogenetic effect was observed with the PAR4-specific antagonist YD-3 [1-benzyl-3(ethoxycarbonylphenyl)-indazole]. These findings may have an important pharmacogenetic effect on the development of new PAR antagonists. PMID:25293779

  18. Mapping transmembrane residues of proteinase activated receptor 2 (PAR2) that influence ligand-modulated calcium signaling.

    PubMed

    Suen, J Y; Adams, M N; Lim, J; Madala, P K; Xu, W; Cotterell, A J; He, Y; Yau, M K; Hooper, J D; Fairlie, D P

    2017-03-01

    Proteinase-activated receptor 2 (PAR2) is a G protein-coupled receptor involved in metabolism, inflammation, and cancers. It is activated by proteolysis, which exposes a nascent N-terminal sequence that becomes a tethered agonist. Short synthetic peptides corresponding to this sequence also activate PAR2, while small organic molecules show promising PAR2 antagonism. Developing PAR2 ligands into pharmaceuticals is hindered by a lack of knowledge of how synthetic ligands interact with and differentially modulate PAR2. Guided by PAR2 homology modeling and ligand docking based on bovine rhodopsin, followed by cross-checking with newer PAR2 models based on ORL-1 and PAR1, site-directed mutagenesis of PAR2 was used to investigate the pharmacology of three agonists (two synthetic agonists and trypsin-exposed tethered ligand) and one antagonist for modulation of PAR2 signaling. Effects of 28 PAR2 mutations were examined for PAR2-mediated calcium mobilization and key mutants were selected for measuring ligand binding. Nineteen of twenty-eight PAR2 mutations reduced the potency of at least one ligand by >10-fold. Key residues mapped predominantly to a cluster in the transmembrane (TM) domains of PAR2, differentially influence intracellular Ca(2+) induced by synthetic agonists versus a native agonist, and highlight subtly different TM residues involved in receptor activation. This is the first evidence highlighting the importance of the PAR2 TM regions for receptor activation by synthetic PAR2 agonists and antagonists. The trypsin-cleaved N-terminus that activates PAR2 was unaffected by residues that affected synthetic peptides, challenging the widespread practice of substituting peptides for proteases to characterize PAR2 physiology.

  19. Solar PAR and UVR modify the community composition and photosynthetic activity of sea ice algae.

    PubMed

    Enberg, Sara; Piiparinen, Jonna; Majaneva, Markus; Vähätalo, Anssi V; Autio, Riitta; Rintala, Janne-Markus

    2015-10-01

    The effects of increased photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) on species diversity, biomass and photosynthetic activity were studied in fast ice algal communities. The experimental set-up consisted of nine 1.44 m(2) squares with three treatments: untreated with natural snow cover (UNT), snow-free (PAR + UVR) and snow-free ice covered with a UV screen (PAR). The total algal biomass, dominated by diatoms and dinoflagellates, increased in all treatments during the experiment. However, the smaller biomass growth in the top 10-cm layer of the PAR + UVR treatment compared with the PAR treatment indicated the negative effect of UVR. Scrippsiella complex (mainly Scrippsiella hangoei, Biecheleria baltica and Gymnodinium corollarium) showed UV sensitivity in the top 5-cm layer, whereas Heterocapsa arctica ssp. frigida and green algae showed sensitivity to both PAR and UVR. The photosynthetic activity was highest in the top 5-cm layer of the PAR treatment, where the biomass of the pennate diatom Nitzschia frigida increased, indicating the UV sensitivity of this species. This study shows that UVR is one of the controlling factors of algal communities in Baltic Sea ice, and that increased availability of PAR together with UVR exclusion can cause changes in algal biomass, photosynthetic activity and community composition.

  20. Participatory Action Research (PAR) cum Action Research (AR) in Teacher Professional Development: A Literature Review

    ERIC Educational Resources Information Center

    Morales, Marie Paz E.

    2016-01-01

    This paper reviews Participatory Action Research as an approach to teacher professional development. It maps the origins of Participatory Action Research (PAR) and discusses the benefits and challenges that have been identified by other researchers in utilizing PAR approaches in conducting research. It draws ideas of combining the features of…

  1. Loss of Par3 promotes lung adenocarcinoma metastasis through 14-3-3ζ protein.

    PubMed

    Song, Tong; Tian, Xia; Kai, Fan; Ke, Jiang; Wei, Zhai; Jing-Song, Li; Si-Hua, Wang; Jian-Jun, Wang

    2016-09-27

    Partitioning defective protein 3 (Par3) can activate the Tiam1/Rac pathway to inhibit invasion and metastasis in many cancers; however, the role of Par3 in lung adenocarcinoma remains unknown. Here we show that Par3 is downregulated in lung adenocarcinoma tissues and is associated with higher rates of lymph node metastasis and recurrence. Our functional study demonstrated that knock-down of Par3 promoted lung adenocarcinoma cell growth, cell migration, tumor formation, and metastasis, all of which were effectively inhibited when 14-3-3ζ was silenced. We found that Par3 binded with 14-3-3ζ protein and also showed that Par3 abrogated the binding of 14-3-3ζ to Tiam1, which was responsible for Rac1 activation. Knock-down of 14-3-3ζ inhibited Tiam1/Rac-GTP activation and blocked the invasive behavior of cells lacking Par3. These data suggest that loss of Par3 promotes metastatic behavior in lung adenocarcinoma cells through 14-3-3ζ protein.

  2. 12 CFR 925.19 - Par value and price of stock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Par value and price of stock. 925.19 Section 925.19 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK MEMBERS AND HOUSING ASSOCIATES MEMBERS OF THE BANKS Stock Requirements § 925.19 Par value and price of stock. The capital...

  3. Human bronchial epithelial cells express PAR-2 with different sensitivity to thermolysin.

    PubMed

    Ubl, Joachim J; Grishina, Zoryana V; Sukhomlin, Tatiana K; Welte, Tobias; Sedehizade, Fariba; Reiser, Georg

    2002-06-01

    Protease-activated receptor-2 (PAR-2) plays a role in inflammatory reactions in airway physiology. Proteases cleaving the extracellular NH(2) terminus of receptors activate or inactivate PAR, thus possessing a therapeutic potential. Using RT-PCR and immunocytochemistry, we show PAR-2 in human airway epithelial cell lines human bronchial epithelial (HBE) and A549. Functional expression of PAR-2 was confirmed by Ca(2+) imaging studies using the receptor agonist protease trypsin. The effect was abolished by soybean trypsin inhibitor and mimicked by the specific PAR-2 peptide agonist SLIGKV. Amplitude and duration of PAR-2-elicited Ca(2+) response in HBE and A549 cells depend on concentration and time of agonist superfusion. The response is partially pertussis toxin (PTX) insensitive, abolished by the phospholipase C inhibitor U-73122, and diminished by the inositol 1,4,5-trisphosphate receptor antagonist 2-aminoethoxydiphenyl borate. Cathepsin G altered neither the resting Ca(2+) level nor PAR-2-elicited Ca(2+) response. Thermolysin, a prototypic bacterial metalloprotease, induced a dose-dependent Ca(2+) response in HBE, but not A549, cells. In both cell lines, thermolysin abolished the response to a subsequent trypsin challenge but not to SLIGKV. Thus different epithelial cell types express different PAR-2 with identical responses to physiological stimuli (trypsin, SLIGKV) but different sensitivity to modifying proteases, such as thermolysin.

  4. Slmb antagonises the aPKC/Par-6 complex to control oocyte and epithelial polarity.

    PubMed

    Morais-de-Sá, Eurico; Mukherjee, Avik; Lowe, Nick; St Johnston, Daniel

    2014-08-01

    The Drosophila anterior-posterior axis is specified when the posterior follicle cells signal to polarise the oocyte, leading to the anterior/lateral localisation of the Par-6/aPKC complex and the posterior recruitment of Par-1, which induces a microtubule reorganisation that localises bicoid and oskar mRNAs. Here we show that oocyte polarity requires Slmb, the substrate specificity subunit of the SCF E3 ubiquitin ligase that targets proteins for degradation. The Par-6/aPKC complex is ectopically localised to the posterior of slmb mutant oocytes, and Par-1 and oskar mRNA are mislocalised. Slmb appears to play a related role in epithelial follicle cells, as large slmb mutant clones disrupt epithelial organisation, whereas small clones show an expansion of the apical domain, with increased accumulation of apical polarity factors at the apical cortex. The levels of aPKC and Par-6 are significantly increased in slmb mutants, whereas Baz is slightly reduced. Thus, Slmb may induce the polarisation of the anterior-posterior axis of the oocyte by targeting the Par-6/aPKC complex for degradation at the oocyte posterior. Consistent with this, overexpression of the aPKC antagonist Lgl strongly rescues the polarity defects of slmb mutant germline clones. The role of Slmb in oocyte polarity raises an intriguing parallel with C. elegans axis formation, in which PAR-2 excludes the anterior PAR complex from the posterior cortex to induce polarity, but its function can be substituted by overexpressing Lgl.

  5. Bacterial DNA segregation dynamics mediated by the polymerizing protein ParF

    PubMed Central

    Barillà, Daniela; Rosenberg, Mark F; Nobbmann, Ulf; Hayes, Finbarr

    2005-01-01

    Prokaryotic DNA segregation most commonly involves members of the Walker-type ParA superfamily. Here we show that the ParF partition protein specified by the TP228 plasmid is a ParA ATPase that assembles into extensive filaments in vitro. Polymerization is potentiated by ATP binding and does not require nucleotide hydrolysis. Analysis of mutations in conserved residues of the Walker A motif established a functional coupling between filament dynamics and DNA partitioning. The partner partition protein ParG plays two separable roles in the ParF polymerization process. ParF is unrelated to prokaryotic polymerizing proteins of the actin or tubulin families, but is a homologue of the MinD cell division protein, which also assembles into filaments. The ultrastructures of the ParF and MinD polymers are remarkably similar. This points to an evolutionary parallel between DNA segregation and cytokinesis in prokaryotic cells, and reveals a potential molecular mechanism for plasmid and chromosome segregation mediated by the ubiquitous ParA-type proteins. PMID:15775965

  6. The parA resolvase performs site-specific genomic excision in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have designed a site-specific excision detection system in Arabidopsis to study the in planta activity of the small serine recombinase ParA. Using a transient expression assay as well as stable transgenic plant lines, we show that the ParA recombinase is catalytically active and capable of perfo...

  7. Questioning Our Questions: Assessing Question Asking Practices to Evaluate a yPAR Program

    ERIC Educational Resources Information Center

    Grace, Sarah; Langhout, Regina Day

    2014-01-01

    The purpose of this research was to examine question asking practices in a youth participatory action research (yPAR) after school program housed at an elementary school. The research question was: In which ways did the adult question asking practices in a yPAR setting challenge and/or reproduce conventional models of power in educational…

  8. Regulation of long-term repopulating hematopoietic stem cells by EPCR/PAR1 signaling

    PubMed Central

    Gur-Cohen, Shiri; Kollet, Orit; Graf, Claudine; Esmon, Charles T.; Ruf, Wolfram; Lapidot, Tsvee

    2016-01-01

    The common developmental origin of endothelial and hematopoietic cells is manifested by coexpression of several cell surface receptors. Adult murine bone marrow (BM) long-term repopulating hematopoietic stem cells (LT-HSCs), endowed with the highest repopulation and self-renewal potential, express endothelial protein C receptor (EPCR), which is used as a marker to isolate them. EPCR/PAR1 signaling in endothelial cells has anticoagulant and anti-inflammatory roles, while thrombin/PAR1 signaling induces coagulation and inflammation. Recent studies define two new PAR1-mediated signaling cascades that regulate EPCR+ LT-HSC BM retention and egress. EPCR/PAR1 signaling facilitates LT-HSC BM repopulation, retention, survival, and chemotherapy resistance by restricting nitric oxide (NO) production, maintaining NOlow LT-HSC BM retention with increased VLA4 expression, affinity, and adhesion. Conversely, acute stress and clinical mobilization upregulate thrombin generation and activate different PAR1 signaling which overcomes BM EPCR+ LT-HSC retention, inducing their recruitment to the bloodstream. Thrombin/PAR1 signaling induces NO generation, TACE-mediated EPCR shedding, and upregulation of CXCR4 and PAR1, leading to CXCL12-mediated stem and progenitor cell mobilization. This review discusses new roles for factors traditionally viewed as coagulation related, which independently act in the BM to regulate PAR1 signaling in bone- and blood-forming progenitor cells, navigating their fate by controlling NO production. PMID:26928241

  9. Loss of Par3 promotes lung adenocarcinoma metastasis through 14-3-3ζ protein

    PubMed Central

    Tong, Song; Xia, Tian; Fan, Kai; Jiang, Ke; Zhai, Wei; Li, Jing-Song; Wang, Si-Hua; Wang, Jian-Jun

    2016-01-01

    Partitioning defective protein 3 (Par3) can activate the Tiam1/Rac pathway to inhibit invasion and metastasis in many cancers; however, the role of Par3 in lung adenocarcinoma remains unknown. Here we show that Par3 is downregulated in lung adenocarcinoma tissues and is associated with higher rates of lymph node metastasis and recurrence. Our functional study demonstrated that knock-down of Par3 promoted lung adenocarcinoma cell growth, cell migration, tumor formation, and metastasis, all of which were effectively inhibited when 14-3-3ζ was silenced. We found that Par3 binded with 14-3-3ζ protein and also showed that Par3 abrogated the binding of 14-3-3ζ to Tiam1, which was responsible for Rac1 activation. Knock-down of 14-3-3ζ inhibited Tiam1/Rac-GTP activation and blocked the invasive behavior of cells lacking Par3. These data suggest that loss of Par3 promotes metastatic behavior in lung adenocarcinoma cells through 14-3-3ζ protein. PMID:27588399

  10. Design and synthesis of peptides from bacterial ParE toxin as inhibitors of topoisomerases.

    PubMed

    Barbosa, Luiz Carlos Bertucci; Garrido, Saulo Santesso; Garcia, Anderson; Delfino, Davi Barbosa; Santos, Laura do Nascimento; Marchetto, Reinaldo

    2012-08-01

    Toxin-antitoxin (TA) proteic systems encode a toxin and an antitoxin that regulate the growth and death of bacterial cells under various stress conditions. The ParE protein is a toxin that inhibits DNA gyrase activity and thereby blocks DNA replication. Based on the Escherichia coli ParE structure, a series of linear peptides were designed and synthesized by solid-phase methodology. The ability of the peptides to inhibit the activity of bacterial topoisomerases was investigated. Four peptides (ParELC3, ParELC8, ParELC10 and ParELC12), showed complete inhibition of DNA gyrase supercoiling activity with an IC(100) between 20 and 40 μmol L(-1). In contrast to wild-type ParE, the peptide analogues were able to inhibit the DNA relaxation of topoisomerase IV, another type IIA bacterial topoisomerase, with lower IC(100) values. Interestingly only ParELC12 displayed inhibition of the relaxation activity of human topoisomerase II. Our findings reveal new inhibitors of bacterial topoisomerases and are a good starting point for the development of a new class of antibacterial agents that targets the DNA topoisomerases.

  11. Compression Myelopathy due to Proliferative Changes around C2 Pars Defects without Instability

    PubMed Central

    Kimura, Tetsuya; Tezuka, Fumitake; Abe, Mitsunobu; Yamashita, Kazuta; Takata, Yoichiro; Higashino, Kosaku; Sairyo, Koichi

    2016-01-01

    We report a case with compression myelopathy due to proliferative changes around the C2 pars defects without instability. A 69-year-old man presented with progressive clumsy hands and spastic gait. Plain radiographs showed bilateral spondylolysis (pars defects) at C2 and fusion between C2 and C3 spinous processes. Dynamic views revealed mobility through the pars defects, but there was no apparent instability. Computed tomography showed proliferative changes at the pars defects, which protruded into spinal canal. On magnetic resonance imaging, the spinal cord was compressed and intramedullary high signal change was found. A diagnosis of compression myelopathy due to proliferative changes around the C2 pars defects was made. We performed posterior decompression. Postoperatively, symptoms have been alleviated and images revealed sufficient decompression and no apparent instability. In patients with the cervical spondylolysis, myelopathy caused by instability or slippage have been periodically reported. The present case involving C2 spondylolysis is extremely rare. PMID:27340539

  12. Loss of the Par3 polarity protein promotes breast tumorigenesis and metastasis.

    PubMed

    McCaffrey, Luke Martin; Montalbano, JoAnne; Mihai, Constantina; Macara, Ian G

    2012-11-13

    Loss of epithelial organization is a hallmark of carcinomas, but whether polarity regulates tumor growth and metastasis is poorly understood. To address this issue, we depleted the Par3 polarity gene by RNAi in combination with oncogenic Notch or Ras(61L) expression in the murine mammary gland. Par3 silencing dramatically reduced tumor latency in both models and produced invasive and metastatic tumors that retained epithelial marker expression. Par3 depletion was associated with induction of MMP9, destruction of the extracellular matrix, and invasion, all mediated by atypical PKC-dependant JAK/Stat3 activation. Importantly, Par3 expression is significantly reduced in human breast cancers, which correlates with active aPKC and Stat3. These data identify Par3 as a regulator of signaling pathways relevant to invasive breast cancer.

  13. PAR Interception and Utilization in Different Maize and Soybean Intercropping Patterns

    PubMed Central

    Liu, Xin; Rahman, Tanzeelur; Yang, Feng; Song, Chun; Yong, Taiwen; Liu, Jiang; Zhang, Cuiying; Yang, Wenyu

    2017-01-01

    The crop intercepted photosynthetically active radiation (PAR) and radiation use efficiency (RUE) vary markedly in different intercropping systems. The HHLA (horizontally homogeneous leaf area) and ERCRT (extended row crop radiation transmission) models have been established to calculate the intercepted PAR for intercrops. However, there is still a lack of study on the intercepted PAR and RUE under different intercropping configurations using different models. To evaluate the intercepted PAR and RUE in maize and soybean under different intercropping systems, we tested different strip intercropping configurations (SI1, SI2, and SI3 based on ERCRT model) and a row intercropping configurations (RI based on HHLA model) in comparison to monoculture. Our results showed that the intercepted PAR and RUE of intercropping systems were all higher than those of monoculture. The soybean intercepted PAR in strip intercropping was 1.35 times greater than that in row intercropping. In row intercropping (RI), the lack of soybean intercepted PAR resulted in a significant reduction of soybean dry matter. Therefore, it is not the recommended configuration for soybean. In strip intercropping patterns, with the distance between maize strip increased by 0.2 m, the intercepted PAR of soybean increased by 20%. The SI2 (maize row spacing at 0.4 m and the distance between maize strip at 1.6 m) was the recommended configuration to achieve the highest value of intercepted PAR and RUE among tested strip intercropping configurations. The method of dry matter estimation using intercepted PAR and RUE is useful in simulated experiments. The simulated value was verified in comparison with experimental data, which confirmed the credibility of the simulation model. Moreover, it also provides help in the development of functional-structural plant model (FSPM). PMID:28056056

  14. Facteurs de risque de mortalité par tuberculose pulmonaire

    PubMed Central

    Janah, Hicham; Souhi, Hicham; Kouismi, Hatim; Mark, Karima; Zahraoui, Rachida; Benamor, Jouda; Soualhi, Mona; Bourkadi, Jamal Eddine

    2014-01-01

    La tuberculose est une maladie infectieuse transmissible provoquée par myco-bacterium tuberculosis (bacille de Koch ou BK). Elle représente, selon les estimations del'Organisation Mondiale de la Santé (OMS), l'une des pathologies infectieuses causant le plus de décès au niveau mondial avec plus de 1 million de décès par an. Pour déterminer les facteurs de risque de mortalité au cours de la tuberculose pulmonaire à microscopie positive nous avons mené une étude rétrospective portant sur tous les cas de tuberculose pulmonaire à microscopie positive et qui étaient décédés au cours de leur hospitalisation. Cette étude a colligé 1803 cas de tuberculose sur une période de 2 ans et demi dont 46 sont décédés. La prévalence de décès est de 2,55%. La population se répartit en 32 hommes et 14 femmes. L’âge moyen était de 53ans ± 17 ans. Le tabagisme était retrouvé chez la moitié des cas. Une comorbidité était retrouvée dans 43%, avec 17% de diabète. Le délai de diagnostic avait une médiane de 60 jours avec percentile (30j; 105j). La symptomatologie clinique était dominée par la toux, la dyspnée et les expectorations soit respectivement: 97,8%, 69,6% et 67,4% des cas. Sur le plan radiologique les lésions étaient diffuses et bilatérales dans 76,1% des cas. Tous les patients étaient mis sous SRHZ. 11% avaient présenté une toxicité aux antibacillaires (de type hépatiques dans 3 cas et neurologiques dans 2 cas). Le délai médian de décès était de 8,5 jours (5j; 17j). Les causes de décès retrouvées étaient: Une hépatite fulminante (3 cas), une décompensation acido-cétosique (3 cas), un SDRA (2 cas), des hémoptysies foudroyantes (2 cas), et respectivement un cas secondaire à une décompensation de BPCO, une décompensation cardiaque, une hypoglycémie et un tableau d'anasarque. Cette étude suggère que le terrain, le retard diagnostique et les effets secondaires du traitement sont les principaux facteurs de risque de

  15. PAR-2 receptor-induced effects on human eccrine sweat gland cells.

    PubMed

    L Bovell, Douglas; Kofler, Barbara; Lang, Roland

    2009-01-01

    Serine proteases can induce cell signaling by stimulating G-protein-coupled receptors, called proteinase-activated receptors (PAR's) on a variety of epithelial cells. While PAR-2, one such receptor, activates cell signaling in a secretory cell line derived from human sweat glands, there was no information on their presence and effects on intact sweat glands. PAR-2 presence and activation of eccrine sweat glands isolated from human skin samples was investigated using Western blot analysis, immunohistochemistry, electron microscopy (EM) and Ca(2+) imaging. Anti-human PAR-2 antibody demonstrated the presence of these receptors in eccrine sweat glands. EM showed that PAR-2 activation resulted in degranulation of secretory cells. Ca(2+) imaging using PAR-2 activators demonstrated a two phase increase in [Ca(2+)](i) which was dependent on extracellular Ca(2+) for the second phase, and that the response could be blocked by prior incubation with xestospongin, the IP(3) receptor blocker. The results demonstrated that PAR-2 receptors are present in human sweat gland secretory cells and that these receptors are functionally active and can induce changes associated with secretory events in eccrine glands.

  16. Blocking PAR2 Alleviates Bladder Pain and Hyperactivity via TRPA1 Signal.

    PubMed

    Chen, Daihui; Liu, Nian; Li, Mao; Liang, Simin

    2016-01-01

    Bladder disorders associated with interstitial cystitis are frequently characterized by increased contractility and pain. The goals of this study were to examine 1) the effects of blocking proteinase-activated receptor-2 (PAR2) on the exaggerated bladder activity and pain evoked by cystitis and 2) the underlying mechanisms responsible for the role of PAR2 in regulating cystic sensory activity. The protein expression of PAR2 was amplified in rats with cystitis by inducing it with systemic administration of cyclophosphamide (CYP) as compared with control rats. Blocking PAR2 by intrathecal infusion of PAR2 antagonist FSLLRY-NH2 attenuated bladder hyperactivity and pain. In addition, blocking PAR2 attenuated the transient receptor potential A1 (TRPA1) signal pathway, whereas inhibition of the TRPA1 decreased bladder hyperactivity and pain. The data revealed specific signaling pathways leading to CYP-induced bladder hyperactivity and pain, including the activation of PAR2 and TRPA1. Inhibition of these pathways alleviates cystic pain. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of overactive bladder and pain often observed in cystitis.

  17. Evidence for a DNA-relay mechanism in ParABS-mediated chromosome segregation.

    PubMed

    Lim, Hoong Chuin; Surovtsev, Ivan Vladimirovich; Beltran, Bruno Gabriel; Huang, Fang; Bewersdorf, Jörg; Jacobs-Wagner, Christine

    2014-05-23

    The widely conserved ParABS system plays a major role in bacterial chromosome segregation. How the components of this system work together to generate translocation force and directional motion remains uncertain. Here, we combine biochemical approaches, quantitative imaging and mathematical modeling to examine the mechanism by which ParA drives the translocation of the ParB/parS partition complex in Caulobacter crescentus. Our experiments, together with simulations grounded on experimentally-determined biochemical and cellular parameters, suggest a novel 'DNA-relay' mechanism in which the chromosome plays a mechanical function. In this model, DNA-bound ParA-ATP dimers serve as transient tethers that harness the elastic dynamics of the chromosome to relay the partition complex from one DNA region to another across a ParA-ATP dimer gradient. Since ParA-like proteins are implicated in the partitioning of various cytoplasmic cargos, the conservation of their DNA-binding activity suggests that the DNA-relay mechanism may be a general form of intracellular transport in bacteria.DOI: http://dx.doi.org/10.7554/eLife.02758.001.

  18. Targeting uPAR with antagonistic recombinant human antibodies in aggressive breast cancer.

    PubMed

    LeBeau, Aaron M; Duriseti, Sai; Murphy, Stephanie T; Pepin, Francois; Hann, Byron; Gray, Joe W; VanBrocklin, Henry F; Craik, Charles S

    2013-04-01

    Components of the plasminogen activation system, which are overexpressed in aggressive breast cancer subtypes, offer appealing targets for development of new diagnostics and therapeutics. By comparing gene expression data in patient populations and cultured cell lines, we identified elevated levels of the urokinase plasminogen activation receptor (uPAR, PLAUR) in highly aggressive breast cancer subtypes and cell lines. Recombinant human anti-uPAR antagonistic antibodies exhibited potent binding in vitro to the surface of cancer cells expressing uPAR. In vivo these antibodies detected uPAR expression in triple negative breast cancer (TNBC) tumor xenografts using near infrared imaging and (111)In single-photon emission computed tomography. Antibody-based uPAR imaging probes accurately detected small disseminated lesions in a tumor metastasis model, complementing the current clinical imaging standard (18)F-fluorodeoxyglucose at detecting non-glucose-avid metastatic lesions. A monotherapy study using the antagonistic antibodies resulted in a significant decrease in tumor growth in a TNBC xenograft model. In addition, a radioimmunotherapy study, using the anti-uPAR antibodies conjugated to the therapeutic radioisotope (177)Lu, found that they were effective at reducing tumor burden in vivo. Taken together, our results offer a preclinical proof of concept for uPAR targeting as a strategy for breast cancer diagnosis and therapy using this novel human antibody technology.

  19. Blocking PAR2 Alleviates Bladder Pain and Hyperactivity via TRPA1 Signal

    PubMed Central

    Chen, Daihui; Liu, Nian; Li, Mao

    2016-01-01

    Abstract Bladder disorders associated with interstitial cystitis are frequently characterized by increased contractility and pain. The goals of this study were to examine 1) the effects of blocking proteinase-activated receptor-2 (PAR2) on the exaggerated bladder activity and pain evoked by cystitis and 2) the underlying mechanisms responsible for the role of PAR2 in regulating cystic sensory activity. The protein expression of PAR2 was amplified in rats with cystitis by inducing it with systemic administration of cyclophosphamide (CYP) as compared with control rats. Blocking PAR2 by intrathecal infusion of PAR2 antagonist FSLLRY-NH2 attenuated bladder hyperactivity and pain. In addition, blocking PAR2 attenuated the transient receptor potential A1 (TRPA1) signal pathway, whereas inhibition of the TRPA1 decreased bladder hyperactivity and pain. The data revealed specific signaling pathways leading to CYP-induced bladder hyperactivity and pain, including the activation of PAR2 and TRPA1. Inhibition of these pathways alleviates cystic pain. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of overactive bladder and pain often observed in cystitis. PMID:28123833

  20. PAR1 activation induces rapid changes in glutamate uptake and astrocyte morphology

    PubMed Central

    Sweeney, Amanda M.; Fleming, Kelsey E.; McCauley, John P.; Rodriguez, Marvin F.; Martin, Elliot T.; Sousa, Alioscka A.; Leapman, Richard D.; Scimemi, Annalisa

    2017-01-01

    The G-protein coupled, protease-activated receptor 1 (PAR1) is a membrane protein expressed in astrocytes. Fine astrocytic processes are in tight contact with neurons and blood vessels and shape excitatory synaptic transmission due to their abundant expression of glutamate transporters. PAR1 is proteolytically-activated by bloodstream serine proteases also involved in the formation of blood clots. PAR1 activation has been suggested to play a key role in pathological states like thrombosis, hemostasis and inflammation. What remains unclear is whether PAR1 activation also regulates glutamate uptake in astrocytes and how this shapes excitatory synaptic transmission among neurons. Here we show that, in the mouse hippocampus, PAR1 activation induces a rapid structural re-organization of the neuropil surrounding glutamatergic synapses, which is associated with faster clearance of synaptically-released glutamate from the extracellular space. This effect can be recapitulated using realistic 3D Monte Carlo reaction-diffusion simulations, based on axial scanning transmission electron microscopy (STEM) tomography reconstructions of excitatory synapses. The faster glutamate clearance induced by PAR1 activation leads to short- and long-term changes in excitatory synaptic transmission. Together, these findings identify PAR1 as an important regulator of glutamatergic signaling in the hippocampus and a possible target molecule to limit brain damage during hemorrhagic stroke. PMID:28256580

  1. Par-4/NF-κB Mediates the Apoptosis of Islet β Cells Induced by Glucolipotoxicity

    PubMed Central

    QiNan, Wu; XiaGuang, Gan; XiaoTian, Lei; WuQuan, Deng; Ling, Zhang; Bing, Chen

    2016-01-01

    Apoptosis of islet β cells is a primary pathogenic feature of type 2 diabetes, and ER stress and mitochondrial dysfunction play important roles in this process. Previous research has shown that prostate apoptosis response-4 (Par-4)/NF-κB induces cancer cell apoptosis through endoplasmic reticulum (ER) stress and mitochondrial dysfunction. However, the mechanism by which Par-4/NF-κB induces islet β cell apoptosis remains unknown. We used a high glucose/palmitate intervention to mimic type 2 diabetes in vitro. We demonstrated that the high glucose/palmitate intervention induced the expression and secretion of Par-4. It also causes increased expression and activation of NF-κB, which induced NIT-1 cell apoptosis and dysfunction. Overexpression of Par-4 potentiates these effects, whereas downregulation of Par-4 attenuates them. Inhibition of NF-κB inhibited the Par-4-induced apoptosis. Furthermore, these effects occurred through the ER stress cell membrane and mitochondrial pathway of apoptosis. Our findings reveal a novel role for Par-4/NF-κB in islet β cell apoptosis and type 2 diabetes. PMID:27340675

  2. CERCLA interim action at the Par Pond unit: A case study

    SciTech Connect

    Hickey, H.M.; Matthews, S.S.; Neal, L.W.; Weiss, W.R.

    1993-11-01

    The Par Pond unit designated under CERCLA consists of sediments within a Savannah River Site (SRS) cooling water reservoir. The sediments are contaminated with radionuclides and nonradioactive constituents from nuclear production reactor operations. The mercury in Par Pond is believed to have originated from the Savannah River. Because of Par Pond Dam safety Issues, the water level of the reservoir was drawn down, exposing more than 1300 acres of contaminated sediments and triggering the need for CERCLA interim remedial action. This paper presents the interim action approach taken with Par Pond as a case study. The approach considered the complexity of the Par Pond ecosystem, the large size of Par Pond, the volume of contaminated sediments, and the institutional controls existing at SRS. The Environmental Protection Agency (EPA) considers units with large volumes of low-concentration wastes, as is the case with Par Pond, to be {open_quotes}special sites.{close_quotes} Accordingly, EPA guidance establishes that the range of alternatives developed focus primarily on containment options and other remedial approaches that mitigate potential risks associated with the {open_quotes}special site.{close_quotes} The remedial alternatives, according to EPA, are not to be prohibitively expensive or difficult to implement. This case study also is representative of the types of issues that will need to be addressed within the Department of Energy (DOE) complex as nuclear facilities are transitioned to inactive status and corrective/remedial actions are warranted.

  3. Protease-activated receptors (PARs)--biology and role in cancer invasion and metastasis.

    PubMed

    Wojtukiewicz, Marek Z; Hempel, Dominika; Sierko, Ewa; Tucker, Stephanie C; Honn, Kenneth V

    2015-12-01

    Although many studies have demonstrated that components of the hemostatic system may be involved in signaling leading to cancer progression, the potential mechanisms by which they contribute to cancer dissemination are not yet precisely understood. Among known coagulant factors, tissue factor (TF) and thrombin play a pivotal role in cancer invasion. They may be generated in the tumor microenvironment independently of blood coagulation and can induce cell signaling through activation of protease-activated receptors (PARs). PARs are transmembrane G-protein-coupled receptors (GPCRs) that are activated by a unique proteolytic mechanism. They play important roles in vascular physiology, neural tube closure, hemostasis, and inflammation. All of these agents (TF, thrombin, PARs-mainly PAR-1 and PAR-2) are thought to promote cancer invasion and metastasis at least in part by facilitating tumor cell migration, angiogenesis, and interactions with host vascular cells, including platelets, fibroblasts, and endothelial cells lining blood vessels. Here, we discuss the role of PARs and their activators in cancer progression, focusing on TF- and thrombin-mediated actions. Therapeutic options tailored specifically to inhibit PAR-induced signaling in cancer patients are presented as well.

  4. Plaies des membres par agression: analyse de 245 dossiers

    PubMed Central

    Boufettal, Monsef; Mahfoud, Mustapha; Ismael, Farid; Kharmaz, Mohamed; Bardouni, Ahmed El; Berrada, Mohamed Saleh; Yaacoubi, Moradh El

    2015-01-01

    Il s'agit d'une étuderétrospective, analytique, monocentrique rentrant dans le cadre d'une étude épidémiologique s’étalant sur une période de trois années (de 2010 à 2012) durant laquelle nous avons revu les dossiers de 245 patients victimes de violence et d'agression. Nous avons exclu les lésions simples traitées en ambulatoire. Par conséquent, nous nous sommes limités aux cas de blessures ayant nécessité une prise en charge spécialisée au bloc opératoire. Les objectifs de notre travail étaient de connaitre la fréquence des agressions au service de traumatologie du CHU de Rabat, classer les différents types de lésions, évaluer leur gravité, mettre la lumière sur les populations les plus touchées et enfin montrer les différentes modalités de prise en charge thérapeutiques. PMID:26918078

  5. Photometric monitoring of the young star Par 1724 in Orion

    NASA Astrophysics Data System (ADS)

    Neuhäuser, R.; Koeltzsch, A.; Raetz, St.; Schmidt, T. O. B.; Mugrauer, M.; Young, N.; Bertoldi, F.; Roell, T.; Eisenbeiss, T.; Hohle, M. M.; Vaňko, M.; Ginski, C.; Rammo, W.; Moualla, M.; Broeg, C.

    2009-05-01

    We report new photometric observations of the ˜ 200 000 year old naked weak-line run-away T Tauri star Par 1724, located north of the Trapezium cluster in Orion. We observed in the broad band filters B, V, R, and I using the 90 cm Dutch telescope on La Silla, the 80 cm Wendelstein telescope, and a 25 cm telescope of the University Observatory Jena in Großschwabhausen near Jena. The photometric data in V and R are consistent with a ˜ 5.7 day rotation period due to spots, as observed before between 1960ies and 2000. Also, for the first time, we present evidence for a long-term 9 or 17.5 year cycle in photometric data (V band) of such a young star, a cycle similar to that to of the Sun and other active stars. Based on observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University; a telescope of the University Observatory Munich on Mount Wendelstein, the 0.9m ESO-Dutch telescope on La Silla, Chile, and with the All Sky Automated Survey (ASAS) project (www.astrouw.edu.pl/asas).

  6. [Development of agonists/antagonists for protease-activated receptors (PARs) and the possible therapeutic application to gastrointestinal diseases].

    PubMed

    Sekiguchi, Fumiko

    2005-06-01

    Protease-activated receptors (PARs), a family of G-protein-coupled seven-transmembrane-domain receptors, are activated by proteolytic unmasking of the N-terminal cryptic tethered ligand by certain serine proteases. Among four PAR family members cloned to date, PAR-1, PAR-2, and PAR-4 can also be activated through a non-enzymatic mechanism, which is achieved by direct binding of exogenously applied synthetic peptides based on the tethered ligand sequence, known as PARs-activating peptides, to the body of the receptor. Various peptide mimetics have been synthesized as agonists for PARs with improved potency, selectivity, and stability. Some peptide mimetics and/or nonpeptide compounds have also been developed as antagonists for PAR-1 and PAR-4. PARs are widely distributed in the mammalian body, especially throughout the alimentary systems, and play various roles in physiological/pathophysiological conditions, i.e., modulation of salivary, gastric, or pancreatic glandular exocrine secretion, gastrointestinal smooth muscle motility, gastric mucosal cytoprotection, suppression/facilitation of visceral pain and inflammation, etc. Thus PARs are now considered novel therapeutic targets, and development of selective agonists and/or antagonists for PARs might provide a novel strategy for the treatment of various diseases that are resistant to current therapeutics.

  7. Caractérisation par ellipsométrie spectroscopique de films minces de tellurure de bismuth obtenus par voie électrochimique

    NASA Astrophysics Data System (ADS)

    Zimmer, A.; Stein, N.; Boulanger, C.; Johann, L.

    2004-12-01

    Des films de tellurure de bismuth (Bi2Te3) d’épaisseur proche de 1 mm ont été développés par voie électrochimique. Leurs indices optiques ont été déterminés par ellipsométrie spectroscopique (SE). Le domaine spectral des indices optiques s’étend de 400 nm à 1300 nm. L’ellipsométrie spectroscopique à angle d’incidence variable (VASE) a été utilisée pour corréler les données SE. Cette partie a été complétée par des analyses par microscopie à force atomique (AFM) qui ont permis de déterminer la rugosité des films. A partir de ces résultats et en associant l’absorption fondamentale des films de Bi2Te3 à une transition indirecte, l’énergie de bande interdite a été évaluée à 0,3 eV. Par ailleurs des mesures associant ellipsométrie spectroscopique à temps réel et électrochimie ont pu être réalisées. Ainsi les premiers instants de croissance ont été observés.

  8. Evaluation of orthodontists' perception of treatment need and the peer assessment rating (PAR) index.

    PubMed

    McGorray, S P; Wheeler, T T; Keeling, S D; Yurkiewicz, L; Taylor, M G; King, G J

    1999-08-01

    This paper examines the relationship between orthodontists' subjective assessment of treatment need and objective measurements obtained during standardized intra- and extraoral examinations. Logistic regression modeling was used to develop predictive models of treatment need. Data were obtained from 1155 eighth-grade students by four orthodontists who used standardized examination forms to assess demographics, trauma, skeletal relationships, morphologic malocclusion traits, and mandibular function. At the conclusion of the examination, the orthodontist rated the subjective treatment need as none, elective, recommended, soon, or immediate. For some analyses, the categories were collapsed to represent no need and need. The peer assessment rating (PAR) index (American validated version) was computed from the clinical exam findings and scoring of dental models; PAR scores were used to document malocclusion severity and treatment difficulty. Spearman rank correlation coefficients quantified the relationship between PAR scores and need categories. Logistic regression analysis modeled treatment need using components of the PAR index as well as other variables. The components of these models, as well as sensitivity and specificity, were compared with malocclusion severity/treatment difficulty scores obtained from malocclusion assessments using the PAR index. The five subjective treatment need categories and the PAR index scores were significantly correlated (rho = 0.62, p<0.001). Significant differences were detected between the need and no need groups for all PAR components (p<0.001). PAR index scores and predicted probabilities from logistic regression models performed equally well for classification purposes (no need, need). The data suggest that the PAR index is highly correlated with orthodontists' subjective assessment of treatment need when that assessment is made in the absence of financial considerations and patient desires.

  9. Small caliber arterial endothelial cells calcium signals elicited by PAR2 are preserved from endothelial dysfunction

    PubMed Central

    Hennessey, John C; Stuyvers, Bruno D; McGuire, John J

    2015-01-01

    Endothelial cell (EC)-dependent vasodilation by proteinase-activated receptor 2 (PAR2) is preserved in small caliber arteries in disease states where vasodilation by muscarinic receptors is decreased. In this study, we identified and characterized the PAR2-mediated intracellular calcium (Ca2+)-release mechanisms in EC from small caliber arteries in healthy and diseased states. Mesenteric arterial EC were isolated from PAR2 wild-type (WT) and null mice, after saline (controls) or angiotensin II (AngII) infusion, for imaging intracellular calcium and characterizing the calcium-release system by immunofluorescence. EC Ca2+ signals comprised two forms of Ca2+-release events that had distinct spatial-temporal properties and occurred near either the plasmalemma (peripheral) or center of EC. In healthy EC, PAR2-dependent increases in the densities and firing rates of both forms of Ca2+-release were abolished by inositol 1,4,5- trisphosphate receptor (IP3R) inhibitor, but partially reduced by transient potential vanilloid channels inhibitor ruthenium red (RR). Acetylcholine (ACh)-induced less overall Ca2+-release than PAR2 activation, but enhanced selectively the incidence of central events. PAR2-dependent Ca2+-activity, inhibitors sensitivities, IP3R, small- and intermediate-conductance Ca2+-activated potassium channels expressions were unchanged in EC from AngII WT. However, the same cells exhibited decreases in ACh-induced Ca2+-release, RR sensitivity, and endothelial nitric oxide synthase expression, indicating AngII-induced dysfunction was differentiated by receptor, Ca2+-release, and downstream targets of EC activation. We conclude that PAR2 and muscarinic receptors selectively elicit two elementary Ca2+ signals in single EC. PAR2-selective IP3R-dependent peripheral Ca2+-release mechanisms are identical between healthy and diseased states. Further study of PAR2-selective Ca2+-release for eliciting pathological and/or normal EC functions is warranted. PMID:25729579

  10. KSHV-Mediated Regulation of Par3 and SNAIL Contributes to B-Cell Proliferation

    PubMed Central

    Jha, Hem C.; Sun, Zhiguo; Upadhyay, Santosh K.; El-Naccache, Darine W.; Singh, Rajnish K.; Sahu, Sushil K.; Robertson, Erle S.

    2016-01-01

    Studies have suggested that Epithelial–Mesenchymal Transition (EMT) and transformation is an important step in progression to cancer. Par3 (partitioning-defective protein) is a crucial factor in regulating epithelial cell polarity. However, the mechanism by which the latency associated nuclear antigen (LANA) encoded by Kaposi's Sarcoma associated herpesvirus (KSHV) regulates Par3 and EMTs markers (Epithelial-Mesenchymal Transition) during viral-mediated B-cell oncogenesis has not been fully explored. Moreover, several studies have demonstrated a crucial role for EMT markers during B-cell malignancies. In this study, we demonstrate that Par3 is significantly up-regulated in KSHV-infected primary B-cells. Further, Par3 interacted with LANA in KSHV positive and LANA expressing cells which led to translocation of Par3 from the cell periphery to a predominantly nuclear signal. Par3 knockdown led to reduced cell proliferation and increased apoptotic induction. Levels of SNAIL was elevated, and E-cadherin was reduced in the presence of LANA or Par3. Interestingly, KSHV infection in primary B-cells led to enhancement of SNAIL and down-regulation of E-cadherin in a temporal manner. Importantly, knockdown of SNAIL, a major EMT regulator, in KSHV cells resulted in reduced expression of LANA, Par3, and enhanced E-cadherin. Also, SNAIL bound to the promoter region of p21 and can regulate its activity. Further a SNAIL inhibitor diminished NF-kB signaling through upregulation of Caspase3 in KSHV positive cells in vitro. This was also supported by upregulation of SNAIL and Par3 in BC-3 transplanted NOD-SCID mice which has potential as a therapeutic target for KSHV-associated B-cell lymphomas. PMID:27463802

  11. Prostate apoptosis response 4 (PAR4) expression modulates WNT signaling pathways in MCF7 breast cancer cells: A possible mechanism underlying PAR4-mediated docetaxel chemosensitivity

    PubMed Central

    De Bessa Garcia, Simone Aparecida; Pavanelli, Ana Carolina; Melo, Natália Cruz E; Nagai, Maria Aparecida

    2017-01-01

    Docetaxel is an effective drug for the treatment of metastatic breast cancer. However, the exact mechanisms and/or markers associated with chemosensitivity or resistance to docetaxel remain unclear. We previously showed that the expression of prostate apoptosis response 4 (PAR4) inhibits the growth of MCF7 breast cancer cells and increases their sensitivity to docetaxel. Using cDNA microarray analysis, we evaluated transcriptome changes in MCF7 cells expressing increased levels of PAR4 and control cells before and after docetaxel treatment. Some of the top gene networks generated from the differentially expressed genes were related to the wingless-type MMTV integration 1 (WNT) canonical (WNT/β-catenin) and non-canonical (β-catenin-independent) pathways. The Human WNT signaling pathway RT2 profiler™ PCR array was used to validate the effects of PAR4 on the expression pattern of genes involved in the WNT pathway. CACNAD2A3, GDF5 and IL6 were upregulated and NANOG was downregulated in the MCF7 breast cancer cells expressing increased levels of PAR4 after treatment with docetaxel, likely indicating inactivation of the WNT/β-catenin pathway. Upregulation of FGF7, LEF1 and TWIST1 indicated activation of the WNT/β-catenin pathway. Although preliminary, our findings could be of particular interest for understanding the action of PAR4 in chemosensitivity, particularly to increase the specificity and effectiveness of drug treatment and overcome resistance to chemotherapy. Further studies are needed to better understand the biological roles of PAR4 in the regulation of WNT pathways in breast cancer cells in response to docetaxel and other chemotherapeutic agents. PMID:28259909

  12. Developpement de techniques de diagnostic non intrusif par tomographie optique

    NASA Astrophysics Data System (ADS)

    Dubot, Fabien

    Que ce soit dans les domaines des procedes industriels ou de l'imagerie medicale, on a assiste ces deux dernieres decennies a un developpement croissant des techniques optiques de diagnostic. L'engouement pour ces methodes repose principalement sur le fait qu'elles sont totalement non invasives, qu'elle utilisent des sources de rayonnement non nocives pour l'homme et l'environnement et qu'elles sont relativement peu couteuses et faciles a mettre en oeuvre comparees aux autres techniques d'imagerie. Une de ces techniques est la Tomographie Optique Diffuse (TOD). Cette methode d'imagerie tridimensionnelle consiste a caracteriser les proprietes radiatives d'un Milieu Semi-Transparent (MST) a partir de mesures optiques dans le proche infrarouge obtenues a l'aide d'un ensemble de sources et detecteurs situes sur la frontiere du domaine sonde. Elle repose notamment sur un modele direct de propagation de la lumiere dans le MST, fournissant les predictions, et un algorithme de minimisation d'une fonction de cout integrant les predictions et les mesures, permettant la reconstruction des parametres d'interet. Dans ce travail, le modele direct est l'approximation diffuse de l'equation de transfert radiatif dans le regime frequentiel tandis que les parametres d'interet sont les distributions spatiales des coefficients d'absorption et de diffusion reduit. Cette these est consacree au developpement d'une methode inverse robuste pour la resolution du probleme de TOD dans le domaine frequentiel. Pour repondre a cet objectif, ce travail est structure en trois parties qui constituent les principaux axes de la these. Premierement, une comparaison des algorithmes de Gauss-Newton amorti et de Broyden- Fletcher-Goldfarb-Shanno (BFGS) est proposee dans le cas bidimensionnel. Deux methodes de regularisation sont combinees pour chacun des deux algorithmes, a savoir la reduction de la dimension de l'espace de controle basee sur le maillage et la regularisation par penalisation de Tikhonov

  13. Regulation of the proapoptotic functions of prostate apoptosis response-4 (Par-4) by casein kinase 2 in prostate cancer cells.

    PubMed

    de Thonel, A; Hazoumé, A; Kochin, V; Isoniemi, K; Jego, G; Fourmaux, E; Hammann, A; Mjahed, H; Filhol, O; Micheau, O; Rocchi, P; Mezger, V; Eriksson, J E; Rangnekar, V M; Garrido, C

    2014-01-23

    The proapoptotic protein, prostate apoptosis response-4 (Par-4), acts as a tumor suppressor in prostate cancer cells. The serine/threonine kinase casein kinase 2 (CK2) has a well-reported role in prostate cancer resistance to apoptotic agents or anticancer drugs. However, the mechanistic understanding on how CK2 supports survival is far from complete. In this work, we demonstrate both in rat and humans that (i) Par-4 is a new substrate of the survival kinase CK2 and (ii) phosphorylation by CK2 impairs Par-4 proapoptotic functions. We also unravel different levels of CK2-dependent regulation of Par-4 between species. In rats, the phosphorylation by CK2 at the major site, S124, prevents caspase-mediated Par-4 cleavage (D123) and consequently impairs the proapoptotic function of Par-4. In humans, CK2 strongly impairs the apoptotic properties of Par-4, independently of the caspase-mediated cleavage of Par-4 (D131), by triggering the phosphorylation at residue S231. Furthermore, we show that human Par-4 residue S231 is highly phosphorylated in prostate cancer cells as compared with their normal counterparts. Finally, the sensitivity of prostate cancer cells to apoptosis by CK2 knockdown is significantly reversed by parallel knockdown of Par-4. Thus, Par-4 seems a critical target of CK2 that could be exploited for the development of new anticancer drugs.

  14. ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data.

    PubMed

    Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S; Windus, Theresa L; Dick-Perez, Marilu

    2017-03-27

    A newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides, important for metal extraction chemistry, are parametrized using ParFit. ParFit is in an open source program available for free on GitHub ( https://github.com/fzahari/ParFit ).

  15. Role of protease-activated receptors 2 (PAR2) in ocular infections and inflammation

    PubMed Central

    Tripathi, Trivendra; Alizadeh, Hassan

    2015-01-01

    Protease-activated receptors (PARs) belong to a unique family of G protein-coupled receptors (GPCRs) that are cleaved at an activation site within the N-terminal exodomain by a variety of proteinases, essentially of the serine (Ser) proteinase family. After cleavage, the new N-terminal sequence functions as a tethered ligand, which binds intramolecularly to activate the receptor and initiate signaling. Cell signals induced through the activation of PARs appear to play a significant role in innate and adoptive immune responses of the cornea, which is constantly exposed to proteinases under physiological or pathophysiological conditions. Activation of PARs interferes with all aspects of the corneal physiology such as barrier function, transports, innate and adoptive immune responses, and functions of corneal nerves. It is not known whether the proteinase released from the microorganism can activate PARs and triggers the inflammatory responses. The role of PAR2 expressed by the corneal epithelial cells and activation by serine protease released from microorganism is discussed here. Recent evidences suggest that activation of PAR2, by the serine proteinases, play an important role in innate and inflammatory responses of the corneal infection. PMID:26078987

  16. The RNA-binding protein ATX-2 regulates cytokinesis through PAR-5 and ZEN-4

    PubMed Central

    Gnazzo, Megan M.; Uhlemann, Eva-Maria E.; Villarreal, Alex R.; Shirayama, Masaki; Dominguez, Eddie G.; Skop, Ahna R.

    2016-01-01

    The spindle midzone harbors both microtubules and proteins necessary for furrow formation and the completion of cytokinesis. However, the mechanisms that mediate the temporal and spatial recruitment of cell division factors to the spindle midzone and midbody remain unclear. Here we describe a mechanism governed by the conserved RNA-binding protein ATX-2/Ataxin-2, which targets and maintains ZEN-4 at the spindle midzone. ATX-2 does this by regulating the amount of PAR-5 at mitotic structures, particularly the spindle, centrosomes, and midbody. Preventing ATX-2 function leads to elevated levels of PAR-5, enhanced chromatin and centrosome localization of PAR-5–GFP, and ultimately a reduction of ZEN-4–GFP at the spindle midzone. Codepletion of ATX-2 and PAR-5 rescued the localization of ZEN-4 at the spindle midzone, indicating that ATX-2 mediates the localization of ZEN-4 upstream of PAR-5. We provide the first direct evidence that ATX-2 is necessary for cytokinesis and suggest a model in which ATX-2 facilitates the targeting of ZEN-4 to the spindle midzone by mediating the posttranscriptional regulation of PAR-5. PMID:27559134

  17. Examining relational empowerment for elementary school students in a yPAR program.

    PubMed

    Langhout, Regina Day; Collins, Charles; Ellison, Erin Rose

    2014-06-01

    This paper joins relational empowerment, youth empowerment, and Bridging Multiple Worlds frameworks to examine forms of relational empowerment for children in two intermediary institutions-school and a youth participatory action research after-school program (yPAR ASP). Participants were twelve children, most of whom were Latina/o and from im/migrant families, enrolled in a yPAR ASP for 2 years. A mixed-method approach was utilized; we analyzed children's interviews, self-defined goals, and their social networks to examine their experiences of relational empowerment. We conclude that children experienced each of the five relational empowerment factors-collaborative competence, bridging social divisions, facilitating others' empowerment, mobilizing networks, and passing on a legacy-in the yPAR ASP setting, and some factors in school. These experiences, however, were more pronounced in the yPAR ASP setting. Additionally, social network analyses revealed that a small but meaningful percentage of actors bridged worlds, especially home and family, but by year 2, also school and the yPAR ASP. Finally, most helpers for school-based goals came from school, but a sizable number came from family, friends, and home worlds, and by year 2, also came from the yPAR ASP. Implications range from theoretical to methodological development, including the use of social network analysis as a tool to descriptively examine relational power in context.

  18. Breaking the epithelial polarity barrier in cancer: the strange case of LKB1/PAR-4

    PubMed Central

    Partanen, Johanna I.; Tervonen, Topi A.; Klefström, Juha

    2013-01-01

    The PAR clan of polarity regulating genes was initially discovered in a genetic screen searching for genes involved in asymmetric cell divisions in the Caenorhabditis elegans embryo. Today, investigations in worms, flies and mammals have established PAR proteins as conserved and fundamental regulators of animal cell polarization in a broad range of biological phenomena requiring cellular asymmetries. The human homologue of invertebrate PAR-4, a serine–threonine kinase LKB1/STK11, has caught attention as a gene behind Peutz–Jeghers polyposis syndrome and as a bona fide tumour suppressor gene commonly mutated in sporadic cancer. LKB1 functions as a master regulator of AMP-activated protein kinase (AMPK) and 12 other kinases referred to as the AMPK-related kinases, including four human homologues of PAR-1. The role of LKB1 as part of the energy sensing LKB1-AMPK module has been intensively studied, whereas the polarity function of LKB1, in the context of homoeostasis or cancer, has gained less attention. Here, we focus on the PAR-4 identity of LKB1, discussing the weight of evidence indicating a role for LKB1 in regulation of cell polarity and epithelial integrity across species and highlight recent investigations providing new insight into the old question: does the PAR-4 identity of LKB1 matter in cancer? PMID:24062587

  19. Ocular trauma treated with pars plana vitrectomy: early outcome report

    PubMed Central

    Mansouri, Mohammad Reza; Tabatabaei, Seyed Ali; Soleimani, Mohammad; Kiarudi, Mohammad Yaser; Molaei, Saber; Rouzbahani, Mehdi; Mireshghi, Meysam; Zaeferani, Mohsen; Ghasempour, Mehrbod

    2016-01-01

    AIM To evaluate demographic variables and visual outcomes, among patients with ocular injuries involving the posterior segment, managed with pars plana vitrectomy. METHODS The records of patients were studied retrospectively from March to September 2010, to determine the age, gender, place of occurrence of trauma, visual acuity, anatomical site, nature of injury, wound length, the presence of an afferent pupillary defect, and the timing of vitrectomy. The Ocular Trauma Score was measured. The minimum follow-up from presentation was 6mo. RESULTS Ninety patients (77 males, 13 females), with a mean age of 32.7±15.8y were included over the 6-month period. The majority of cases occurred in the workplace (47 patients), followed by home (14 patients). The mean visual acuity (logMAR) of patients significantly improved from 2.36±0.72 preoperatively to 1.50±1.14 postoperatively. Twenty-three patients had preoperative vision better than 2.0 logMAR, the postoperative visual acuity was significantly better among these patients than patients with worse than 2.0 logMAR (P<0.001). Visual improvement between groups with early vitrectomy (<7d) and delayed vitrectomy (>7d) was not significantly different (P=0.66). Postoperative visual acuity was not significantly different between patients with injury in Zone I and II (P=0.64), but patients with injury in Zone III had significantly poorer visual acuity (P=0.02). Patients with relative afferent pupillary defect had significantly poorer postoperative visual acuity (P=0.02). Preoperative visual acuity, the difference of preoperative and postoperative visual acuity, and postoperative visual acuity were significantly different between groups with different ocular trauma scores (P<0.001). CONCLUSION Trauma is more likely to occur in men under 40y of age and in the workplace. The favorable final visual outcome is associated with the absence of afferent pupillary defect, ocular trauma score and presenting visual acuity as well as the zone

  20. Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

    NASA Astrophysics Data System (ADS)

    Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm; Iversen, Frank; Liu, Zhuo; Thomsen, Karen; Pedersen, Michael; Skrydstrup, Troels; Nielsen, Niels Chr.; Ploug, Michael; Kjems, Jørgen

    2013-08-01

    Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific

  1. Heat stress-induced disruption of endothelial barrier function is via PAR1 signaling and suppressed by Xuebijing injection.

    PubMed

    Xu, Qiulin; Liu, Jingxian; Wang, Zhenglian; Guo, Xiaohua; Zhou, Gengbiao; Liu, Yanan; Huang, Qiaobing; Su, Lei

    2015-01-01

    Increased vascular permeability leading to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) is central to the pathogenesis of heatstroke. Protease-activated receptor 1 (PAR1), the receptor for thrombin, plays a key role in disruption of endothelial barrier function in response to extracellular stimuli. However, the role of PAR1 in heat stress-induced endothelial hyper-permeability is unknown. In this study, we measured PAR1 protein expression in heat-stressed human umbilical venous endothelial cells (HUVECs), investigated the influences of PAR1 on endothelial permeability, F-actin rearrangement, and moesin phosphorylation by inhibiting PAR1 with its siRNA, neutralizing antibody (anti-PAR1), specific inhibitor(RWJ56110), and Xuebijing injection (XBJ), a traditional Chinese medicine used for sepsis treatment, and evaluated the role of PAR1 in heatstroke-related ALI/ARDS in mice by suppressing PAR1 with RWJ56110, anti-PAR1and XBJ. We found that heat stress induced PAR1 protein expression 2h after heat stress in endothelial cells, caused the release of endothelial matrix metalloprotease 1, an activator of PAR1, after 60 or 120 min of heat stimulation, as well as promoted endothelial hyper-permeability and F-actin rearrangement, which were inhibited by suppressing PAR1 with RWJ56110, anti-PAR1 and siRNA. PAR1 mediated moesin phosphorylation, which caused F-actin rearrangement and disruption of endothelial barrier function. To corroborate findings from in vitro experiments, we found that RWJ56110 and the anti-PAR1 significantly decreased lung edema, pulmonary microvascular permeability, protein exudation, and leukocytes infiltrations in heatstroke mice. Additionally, XBJ was found to suppress PAR1-moesin signal pathway and confer protective effects on maintaining endothelial barrier function both in vitro and in vivo heat-stressed model, similar to those observed above with the inhibition of PAR1. These results suggest that PAR1 is a potential

  2. Post-translational regulation of the cleaved fragment of Par-4 in ovarian and endometrial cancer cells

    PubMed Central

    Brasseur, Kevin; Fabi, François; Adam, Pascal; Parent, Sophie; Lessard, Laurent; Asselin, Eric

    2016-01-01

    We recently reported the caspase3-dependent cleavage of Par-4 resulting in the accumulation of a 25kDa cleaved-Par-4 (cl-Par-4) fragment and we investigated in the present study the mechanisms regulating this fragment using cl-Par-4-expressing stable clones derived from ovarian and endometrial cancer cell lines. Cl-Par-4 protein was weakly express in all stable clones despite constitutive expression. However, upon cisplatin treatment, cl-Par-4 levels increased up to 50-fold relative to baseline conditions. Treatment of stable clones with proteasome and translation inhibitors revealed that cisplatin exposure might in fact protect cl-Par-4 from proteasome-dependent degradation. PI3K and MAPK pathways were also implicated as evidenced by an increase of cl-Par-4 in the presence of PI3K inhibitors and a decrease using MAPK inhibitors. Finally using bioinformatics resources, we found diverse datasets showing similar results to those we observed with the proteasome and cl-Par-4 further supporting our data. These new findings add to the complex mechanisms regulating Par-4 expression and activity, and justify further studies addressing the biological significance of this phenomenon in gynaecological cancer cells. PMID:27175591

  3. Iduna is a poly(ADP-ribose) (PAR)-dependent E3 ubiquitin ligase that regulates DNA damage

    PubMed Central

    Kang, Ho Chul; Lee, Yun-Il; Shin, Joo-Ho; Andrabi, Shaida A.; Chi, Zhikai; Gagné, Jean-Philippe; Lee, Yunjong; Ko, Han Seok; Lee, Byoung Dae; Poirier, Guy G.; Dawson, Valina L.; Dawson, Ted M.

    2011-01-01

    Ubiquitin mediated protein degradation is crucial for regulation of cell signaling and protein quality control. Poly(ADP-ribose) (PAR) is a cell-signaling molecule that mediates changes in protein function through binding at PAR binding sites. Here we characterize the PAR binding protein, Iduna, and show that it is a PAR-dependent ubiquitin E3 ligase. Iduna’s E3 ligase activity requires PAR binding because point mutations at Y156A and R157A eliminate Iduna’s PAR binding and Iduna’s E3 ligase activity. Iduna’s E3 ligase activity also requires an intact really interesting new gene (RING) domain because Iduna possessing point mutations at either H54A or C60A is devoid of ubiquitination activity. Tandem affinity purification reveals that Iduna binds to a number of proteins that are either PARsylated or bind PAR including PAR polymerase-1, 2 (PARP1, 2), nucleolin, DNA ligase III, KU70, KU86, XRCC1, and histones. PAR binding to Iduna activates its E3 ligase function, and PAR binding is required for Iduna ubiquitination of PARP1, XRCC1, DNA ligase III, and KU70. Iduna’s PAR-dependent ubiquitination of PARP1 targets it for proteasomal degradation. Via PAR binding and ubiquitin E3 ligase activity, Iduna protects against cell death induced by the DNA damaging agent N-methyl-N-nitro-N-nitrosoguanidine (MNNG) and rescues cells from G1 arrest and promotes cell survival after γ-irradiation. Moreover, Iduna facilitates DNA repair by reducing apurinic/apyrimidinic (AP) sites after MNNG exposure and facilitates DNA repair following γ-irradiation as assessed by the comet assay. These results define Iduna as a PAR-dependent E3 ligase that regulates cell survival and DNA repair. PMID:21825151

  4. A method for estimating the diffuse attenuation coefficient (KdPAR)from paired temperature sensors

    USGS Publications Warehouse

    Read, Jordan S.; Rose, Kevin C.; Winslow, Luke A.; Read, Emily K.

    2015-01-01

    A new method for estimating the diffuse attenuation coefficient for photosynthetically active radiation (KdPAR) from paired temperature sensors was derived. We show that during cases where the attenuation of penetrating shortwave solar radiation is the dominant source of temperature changes, time series measurements of water temperatures at multiple depths (z1 and z2) are related to one another by a linear scaling factor (a). KdPAR can then be estimated by the simple equation KdPAR ln(a)/(z2/z1). A suggested workflow is presented that outlines procedures for calculating KdPAR according to this paired temperature sensor (PTS) method. This method is best suited for conditions when radiative temperature gains are large relative to physical noise. These conditions occur frequently on water bodies with low wind and/or high KdPARs but can be used for other types of lakes during time periods of low wind and/or where spatially redundant measurements of temperatures are available. The optimal vertical placement of temperature sensors according to a priori knowledge of KdPAR is also described. This information can be used to inform the design of future sensor deployments using the PTS method or for campaigns where characterizing sub-daily changes in temperatures is important. The PTS method provides a novel method to characterize light attenuation in aquatic ecosystems without expensive radiometric equipment or the user subjectivity inherent in Secchi depth measurements. This method also can enable the estimation of KdPAR at higher frequencies than many manual monitoring programs allow.

  5. Detecting Plant Photoprotective Response to Water Stress Through Variation In PAR Reflectance

    NASA Astrophysics Data System (ADS)

    Zygielbaum, A. I.; Arkebauer, T. J.; Walter-Shea, E.

    2012-12-01

    Published papers over several decades have shown increasing leaf-level optical reflectance with decreasing leaf water content. Our experimental results using maize and sorghum showed this increase consistently, caused by variation in optical absorption, in the visible (photosynthetically active radiation - PAR) and middle infrared (MIR) spectral regions. Relatively smaller response, driven by variation in optical scatter, was observed in near infrared (NIR). The concomitant increasing reflectance in the PAR and MIR regions is perplexing. PAR reflectance is dominated by chlorophyll absorption while MIR reflectance is dominated by water molecule absorption. However, changes in chlorophyll concentration, determined by chemical extraction, were too small to account for the variation in PAR reflectance. PAR and MIR reflectances were also influenced by the strength of incident light. Hence PAR reflectance appears to be modulated not only by pigment concentration, the classical description, but also by the strength of incident light and the severity of water deficit. We previously reported that these findings were consistent with chloroplast avoidance movement, a plant photoprotective response, which limits light absorption by pigments. We report here our continuing investigation of this phenomenon. In addition to reflectance measurements, time-lapse microscope images of leaves under increasing water deficit conditions were obtained. These show a brightening between veins which strongly supports our assertion that changes in PAR reflectance accompanying water deficit are caused primarily by chloroplast avoidance movement. Our results suggest that leaf, and possibly canopy, reflectance can therefore be used to detect and measure plant stress. These results also indicate that chloroplast avoidance movement may cause poor estimates of leaf chlorophyll content using techniques based on fluoresced, reflected or transmitted light.

  6. ParsEval: parallel comparison and analysis of gene structure annotations

    PubMed Central

    2012-01-01

    Background Accurate gene structure annotation is a fundamental but somewhat elusive goal of genome projects, as witnessed by the fact that (model) genomes typically undergo several cycles of re-annotation. In many cases, it is not only different versions of annotations that need to be compared but also different sources of annotation of the same genome, derived from distinct gene prediction workflows. Such comparisons are of interest to annotation providers, prediction software developers, and end-users, who all need to assess what is common and what is different among distinct annotation sources. We developed ParsEval, a software application for pairwise comparison of sets of gene structure annotations. ParsEval calculates several statistics that highlight the similarities and differences between the two sets of annotations provided. These statistics are presented in an aggregate summary report, with additional details provided as individual reports specific to non-overlapping, gene-model-centric genomic loci. Genome browser styled graphics embedded in these reports help visualize the genomic context of the annotations. Output from ParsEval is both easily read and parsed, enabling systematic identification of problematic gene models for subsequent focused analysis. Results ParsEval is capable of analyzing annotations for large eukaryotic genomes on typical desktop or laptop hardware. In comparison to existing methods, ParsEval exhibits a considerable performance improvement, both in terms of runtime and memory consumption. Reports from ParsEval can provide relevant biological insights into the gene structure annotations being compared. Conclusions Implemented in C, ParsEval provides the quickest and most feature-rich solution for genome annotation comparison to date. The source code is freely available (under an ISC license) at http://parseval.sourceforge.net/. PMID:22852583

  7. Exacerbation of Apoptosis of Cortical Neurons Following Traumatic Brain Injury in Par-4 Transgenic Mice

    PubMed Central

    Payette, Daniel J; Xie, Jun; Shirwany, Najeeb; Guo, Qing

    2008-01-01

    Traumatic brain injury (TBI) is a significant clinical problem, yet few effective strategies for treating it have emerged. People that sustain and survive a TBI are left with significant cognitive, behavioral, and communicative disabilities. Apoptotic neuronal death occurs following TBI. Prostate apoptosis response-4 (Par-4) is a death domain-containing protein initially characterized as a critical regulator of apoptosis in prostate cancer cells. We have recently generated and characterized Par-4 transgenic mice in which the expression of the par-4 transgene was limited to cells of neuronal lineage. We now provide evidence that, in cortical neurons from these mice, Par-4 drastically increases apoptotic neuronal death in both in vitro and in vivo models of TBI. In vitro experiments were performed in 7-day-old primary cultures of cortical neurons using a previously published, scratch-induced mechanical trauma model. Neurons that overexpress Par-4 showed not only a significant decrease in overall neuron survival after TBI compared to wild-type cells, but also exhibited a sharper decrease in mitochondrial transmembrane potential, a higher degree of free radical accumulation, and earlier activation of caspase-3 than wild-type cells did. In vivo experiments were performed utilizing a weight drop TBI model. A significantly increased volume of cortical injury and exacerbated activation of caspase-3 were observed in Par-4 transgenic mice when compared to those in wild-type mice. These data suggests that aberrant Par-4 expression exacerbates neuronal cell death following TBI by altering mitochondrial function, enhancing oxidative damage, and execution of apoptosis via caspase activation. PMID:18784822

  8. Evaluation of treatment and posttreatment changes of protraction facemask treatment using the PAR index.

    PubMed

    Ngan, P; Yiu, C

    2000-10-01

    The purpose of this study was to use the Peer Assesment Rating (PAR) index score to evaluate the treatment and posttreatment changes of Class III patients treated by protraction facemask. The sample consisted of 20 Chinese children, 6 to 11 years old, with Class III skeletal malocclusion who had been treated with maxillary expansion and a protraction facemask. The average treatment time was 8.2 months, followed by 1 year of retention with a Class III functional appliance. Study casts were taken pretreatment (T1), posttreatment (T2), 1 year follow-up (T3), and 2 years follow-up (T4). After treatment, PAR scores were calculated for each time period. Differences among the 4 time periods were analyzed with the Wilcoxin matched-pairs test. Significant reductions in PAR scores were found at T2 (56%), T3 (70%), and T4 (63%) compared with T1. Immediately posttreatment (T2), 17 (85%) of 20 patients had improved PAR scores by a reduction of at least 30%. Reductions were caused primarily by correction of the anterior crossbite. One year after treatment (T3), further reductions in PAR score were noted (P <.01) as a result of better alignment of the anterior segment, improvement of the buccal occlusion, and overbite and midline corrections. Two years after treatment (T4), PAR scores were higher than at the previous time period. The increases were due to relapses in overjet (4 of 20 patients), overbite, and centerline corrections. These results indicate that significant reductions in the severity of Class III malocclusion can be achieved with early orthopedic facemask treatment. In most cases, further improvement in the PAR score can be expected 1 and 2 years after treatment. In a few patients, the benefits of early treatment are negated by relapses in overjet, overbite, and centerline corrections during the follow-up period.

  9. Cortical Polarity of the RING Protein PAR-2 Is Maintained by Exchange Rate Kinetics at the Cortical-Cytoplasmic Boundary.

    PubMed

    Arata, Yukinobu; Hiroshima, Michio; Pack, Chan-Gi; Ramanujam, Ravikrishna; Motegi, Fumio; Nakazato, Kenichi; Shindo, Yuki; Wiseman, Paul W; Sawa, Hitoshi; Kobayashi, Tetsuya J; Brandão, Hugo B; Shibata, Tatsuo; Sako, Yasushi

    2016-08-23

    Cell polarity arises through the spatial segregation of polarity regulators. PAR proteins are polarity regulators that localize asymmetrically to two opposing cortical domains. However, it is unclear how the spatially segregated PAR proteins interact to maintain their mutually exclusive partitioning. Here, single-molecule detection analysis in Caenorhabditis elegans embryos reveals that cortical PAR-2 diffuses only short distances, and, as a result, most PAR-2 molecules associate and dissociate from the cortex without crossing into the opposing domain. Our results show that cortical PAR-2 asymmetry is maintained by the local exchange reactions that occur at the cortical-cytoplasmic boundary. Additionally, we demonstrate that local exchange reactions are sufficient to maintain cortical asymmetry in a parameter-free mathematical model. These findings suggest that anterior and posterior PAR proteins primarily interact through the cytoplasmic pool and not via cortical diffusion.

  10. EBV LMP-1 negatively regulates expression and pro-apoptotic activity of Par-4 in nasopharyngeal carcinoma cells.

    PubMed

    Lee, Jeng-Woei; Liu, Po-Fan; Hsu, Lee-Ping; Chen, Peir-Rong; Chang, Chung-Hsing; Shih, Wen-Ling

    2009-07-08

    Latent membrane protein-1 (LMP-1) of the Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma (NPC), and in this study we sought to determine whether the pro-apoptotic activity of prostate apoptosis response-4 (Par-4) is modulated by LMP-1 in NPC cells. We found that LMP-1 diminished the pro-apoptotic activity of Par-4 and negatively regulated Par-4 protein by de novo synthesis; moreover, although LMP-1 accelerated a Par-4 activator, PKA, we demonstrated that LMP-1 also activated the PI3K/Akt pathway and increased Bcl-2 expression to suppress the activity of Par-4. Consequently, our results revealed a novel negative action of LMP-1 on the pro-apoptosis protein Par-4 by the coordination of multiple signaling pathways.

  11. Spatiotemporal Variability of Global and Diffuse PAR in the Amazon Region and its Significance for Tropical Forest Photosynthesis

    NASA Astrophysics Data System (ADS)

    Dye, D. G.

    2003-12-01

    This study examines seasonal and inter-annual variation in surface fluxes of global and diffuse photosynthetically active radiation (PAR, 400-700 nm) in the tropical forest of the Amazon region. Spatial and temporal patterns of global and diffuse PAR are determined from reanalysis data from the National Center for Environmental Prediction (NCEP), and from the SeaWIFS Solar Surface Irradiance (SSI) data set. The PAR data and satellite-derived estimates of leaf area index (LAI) are applied to an existing sun-shade model of forest canopy photosynthesis. The seasonality of atmospheric scattering (quantified as the diffuse fraction of global PAR) as a determining factor for the relative influence of variation and trends in incident PAR on tropical forest photosynthesis is quantitatively evaluated. The results provide insight into the role of the surface PAR regime in the dynamics of ecosystem-atmosphere carbon exchange in the Amazon and other tropical forest regions.

  12. Active zone proteins are transported via distinct mechanisms regulated by Par-1 kinase

    PubMed Central

    Barber, Kara R.; Sherman, Michael

    2017-01-01

    Disruption of synapses underlies a plethora of neurodevelopmental and neurodegenerative disease. Presynaptic specialization called the active zone plays a critical role in the communication with postsynaptic neuron. While the role of many proteins at the active zones in synaptic communication is relatively well studied, very little is known about how these proteins are transported to the synapses. For example, are there distinct mechanisms for the transport of active zone components or are they all transported in the same transport vesicle? Is active zone protein transport regulated? In this report we show that overexpression of Par-1/MARK kinase, a protein whose misregulation has been implicated in Autism spectrum disorders (ASDs) and neurodegenerative disorders, lead to a specific block in the transport of an active zone protein component- Bruchpilot at Drosophila neuromuscular junctions. Consistent with a block in axonal transport, we find a decrease in number of active zones and reduced neurotransmission in flies overexpressing Par-1 kinase. Interestingly, we find that Par-1 acts independently of Tau-one of the most well studied substrates of Par-1, revealing a presynaptic function for Par-1 that is independent of Tau. Thus, our study strongly suggests that there are distinct mechanisms that transport components of active zones and that they are tightly regulated. PMID:28222093

  13. Role of PAR2 in regulating oxaliplatin-induced neuropathic pain via TRPA1.

    PubMed

    Tian, Liujun; Fan, Tianren; Zhou, Nan; Guo, Hui; Zhang, Weijie

    2015-01-01

    Oxaliplatin (OXL) is a third-generation chemotherapeutic agent commonly used to treat metastatic digestive tumors; however, one of the main limiting complications of OXL is neuropathic pain. In this study, the underlying mechanisms responsible for OXL evoked-neuropathic pain were examined. Using a rat model, the results demonstrated that intraperitoneal (i.p.) injection of OXL significantly increased mechanical pain and cold sensitivity as compared with control animals (P < 0.05 vs. control rats). Blocking proteinase-activated receptor 2 (PAR2) significantly attenuated mechanical pain and cold sensitivity observed in control rats and OXL rats (P < 0.05 vs. vehicle control). The attenuating effect of PAR2 on mechanical pain and cold sensitivity were significantly smaller in OXL-rats than in control rats. The role played by PAR2 downstream signaling pathways [namely, transient receptor potential ankyrin 1 (TRPA1)] in regulating OXL evoked-neuropathic pain was also examined. The data shows that TRPA1 expression was upregulated in the lumbar dorsal root ganglion (DRG) of OXL rats and blocking TRPA1 inhibited mechanical pain and heightened cold sensitivity (P < 0.05 vs. control rats). Blocking PAR2 also significantly decreased TRPA1 expression in the DRG. Findings in this study show that OXL intervention amplifies mechanical hyperalgesia and cold hypersensitivity and PAR2 plays an important role in regulating OXL-induced neuropathic pain via TRPA1 pathways.

  14. Sensitization of TRPA1 by PAR2 contributes to the sensation of inflammatory pain.

    PubMed

    Dai, Yi; Wang, Shenglan; Tominaga, Makoto; Yamamoto, Satoshi; Fukuoka, Tetsuo; Higashi, Tomohiro; Kobayashi, Kimiko; Obata, Koichi; Yamanaka, Hiroki; Noguchi, Koichi

    2007-07-01

    Proinflammatory agents trypsin and mast cell tryptase cleave and activate PAR2, which is expressed on sensory nerves to cause neurogenic inflammation. Transient receptor potential A1 (TRPA1) is an excitatory ion channel on primary sensory nerves of pain pathway. Here, we show that a functional interaction of PAR2 and TRPA1 in dorsal root ganglion (DRG) neurons could contribute to the sensation of inflammatory pain. Frequent colocalization of TRPA1 with PAR2 was found in rat DRG neurons. PAR2 activation increased the TRPA1 currents evoked by its agonists in HEK293 cells transfected with TRPA1, as well as DRG neurons. Application of phospholipase C (PLC) inhibitors or phosphatidylinositol-4,5-bisphosphate (PIP(2)) suppressed this potentiation. Decrease of plasma membrane PIP(2) levels through antibody sequestration or PLC-mediated hydrolysis mimicked the potentiating effects of PAR2 activation at the cellular level. Thus, the increased TRPA1 sensitivity may have been due to activation of PLC, which releases the inhibition of TRPA1 from plasma membrane PIP(2). These results identify for the first time to our knowledge a sensitization mechanism of TRPA1 and a novel mechanism through which trypsin or tryptase released in response to tissue inflammation might trigger the sensation of pain by TRPA1 activation.

  15. Nanomechanical recognition of prognostic biomarker suPAR with DVD-ROM optical technology

    NASA Astrophysics Data System (ADS)

    Bache, Michael; Bosco, Filippo G.; Brøgger, Anna L.; Frøhling, Kasper B.; Sonne Alstrøm, Tommy; Hwu, En-Te; Chen, Ching-Hsiu; Eugen-Olsen, Jesper; Hwang, Ing-Shouh; Boisen, Anja

    2013-11-01

    In this work the use of a high-throughput nanomechanical detection system based on a DVD-ROM optical drive and cantilever sensors is presented for the detection of urokinase plasminogen activator receptor inflammatory biomarker (uPAR). Several large scale studies have linked elevated levels of soluble uPAR (suPAR) to infectious diseases, such as HIV, and certain types of cancer. Using hundreds of cantilevers and a DVD-based platform, cantilever deflection response from antibody-antigen recognition is investigated as a function of suPAR concentration. The goal is to provide a cheap and portable detection platform which can carry valuable prognostic information. In order to optimize the cantilever response the antibody immobilization and unspecific binding are initially characterized using quartz crystal microbalance technology. Also, the choice of antibody is explored in order to generate the largest surface stress on the cantilevers, thus increasing the signal. Using optimized experimental conditions the lowest detectable suPAR concentration is currently around 5 nM. The results reveal promising research strategies for the implementation of specific biochemical assays in a portable and high-throughput microsensor-based detection platform.

  16. Nanomechanical recognition of prognostic biomarker suPAR with DVD-ROM optical technology.

    PubMed

    Bache, Michael; Bosco, Filippo G; Brøgger, Anna L; Frøhling, Kasper B; Alstrøm, Tommy Sonne; Hwu, En-Te; Chen, Ching-Hsiu; Eugen-Olsen, Jesper; Hwang, Ing-Shouh; Boisen, Anja

    2013-11-08

    In this work the use of a high-throughput nanomechanical detection system based on a DVD-ROM optical drive and cantilever sensors is presented for the detection of urokinase plasminogen activator receptor inflammatory biomarker (uPAR). Several large scale studies have linked elevated levels of soluble uPAR (suPAR) to infectious diseases, such as HIV, and certain types of cancer. Using hundreds of cantilevers and a DVD-based platform, cantilever deflection response from antibody-antigen recognition is investigated as a function of suPAR concentration. The goal is to provide a cheap and portable detection platform which can carry valuable prognostic information. In order to optimize the cantilever response the antibody immobilization and unspecific binding are initially characterized using quartz crystal microbalance technology. Also, the choice of antibody is explored in order to generate the largest surface stress on the cantilevers, thus increasing the signal. Using optimized experimental conditions the lowest detectable suPAR concentration is currently around 5 nM. The results reveal promising research strategies for the implementation of specific biochemical assays in a portable and high-throughput microsensor-based detection platform.

  17. Lambeaux autofermants pour le traitement des brulures electriques du scalp par haut voltage

    PubMed Central

    Hafidi, J.; El Mazouz, S.; El Mejatti, H.; Fejjal, N.; Gharib, N.E.; Abbassi, A.; Belmahi, A.M.

    2011-01-01

    Summary Les brûlures électriques par haut voltage sont responsables de gros dégâts tissulaires en immédiat et dans les jours suivant l’accident du fait de la chaleur importante dégagée par effet joule et de la thrombose microvasculaire évolutive. Les pertes de substances du scalp secondaires à ces brûlures nécessitent une couverture par lambeaux vu la destruction du périoste et du calvarium en regard. De juin 1997 à juin 2008, 15 patients ont été traités pour des pertes de substance du scalp secondaires à des brûlures électriques par haut voltage de diamètre allant de 8 à 11 cm et siégeant dans la région tonsurale. Ces patients ont été opérés dans la première semaine suivant l’accident. Les pertes de substance du scalp de taille moyenne secondaires à ces brûlures peuvent être couvertes per primam de façon fiable par des lambeaux locaux axialisés et multiples. Nous relatons l’expérience du Service de Chirurgie Plastique du Centre Hospitalier Universitaire Ibn-Sina, Rabat, Maroc, dans la gestion et la prise en charge de ces brûlures. PMID:22262963

  18. Towards an improved LAI collection protocol via simulated field-based PAR sensing

    DOE PAGES

    Yao, Wei; Van Leeuwen, Martin; Romanczyk, Paul; ...

    2016-07-14

    In support of NASA’s next-generation spectrometer—the Hyperspectral Infrared Imager (HyspIRI)—we are working towards assessing sub-pixel vegetation structure from imaging spectroscopy data. Of particular interest is Leaf Area Index (LAI), which is an informative, yet notoriously challenging parameter to efficiently measure in situ. While photosynthetically-active radiation (PAR) sensors have been validated for measuring crop LAI, there is limited literature on the efficacy of PAR-based LAI measurement in the forest environment. This study (i) validates PAR-based LAI measurement in forest environments, and (ii) proposes a suitable collection protocol, which balances efficiency with measurement variation, e.g., due to sun flecks and various-sized canopymore » gaps. A synthetic PAR sensor model was developed in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model and used to validate LAI measurement based on first-principles and explicitly-known leaf geometry. Simulated collection parameters were adjusted to empirically identify optimal collection protocols. Furthermore, these collection protocols were then validated in the field by correlating PAR-based LAI measurement to the normalized difference vegetation index (NDVI) extracted from the “classic” Airborne Visible Infrared Imaging Spectrometer (AVIRIS-C) data (R2 was 0.61). The results indicate that our proposed collecting protocol is suitable for measuring the LAI of sparse forest (LAI < 3–5 ( m2/m2)).« less

  19. Towards an improved LAI collection protocol via simulated field-based PAR sensing

    SciTech Connect

    Yao, Wei; Van Leeuwen, Martin; Romanczyk, Paul; van Aardt, Jan; Kelbe, David

    2016-07-14

    In support of NASA’s next-generation spectrometer—the Hyperspectral Infrared Imager (HyspIRI)—we are working towards assessing sub-pixel vegetation structure from imaging spectroscopy data. Of particular interest is Leaf Area Index (LAI), which is an informative, yet notoriously challenging parameter to efficiently measure in situ. While photosynthetically-active radiation (PAR) sensors have been validated for measuring crop LAI, there is limited literature on the efficacy of PAR-based LAI measurement in the forest environment. This study (i) validates PAR-based LAI measurement in forest environments, and (ii) proposes a suitable collection protocol, which balances efficiency with measurement variation, e.g., due to sun flecks and various-sized canopy gaps. A synthetic PAR sensor model was developed in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model and used to validate LAI measurement based on first-principles and explicitly-known leaf geometry. Simulated collection parameters were adjusted to empirically identify optimal collection protocols. Furthermore, these collection protocols were then validated in the field by correlating PAR-based LAI measurement to the normalized difference vegetation index (NDVI) extracted from the “classic” Airborne Visible Infrared Imaging Spectrometer (AVIRIS-C) data (R2 was 0.61). The results indicate that our proposed collecting protocol is suitable for measuring the LAI of sparse forest (LAI < 3–5 ( m2/m2)).

  20. Towards an Improved LAI Collection Protocol via Simulated and Field-Based PAR Sensing

    PubMed Central

    Yao, Wei; Kelbe, David; van Leeuwen, Martin; Romanczyk, Paul; van Aardt, Jan

    2016-01-01

    In support of NASA’s next-generation spectrometer—the Hyperspectral Infrared Imager (HyspIRI)—we are working towards assessing sub-pixel vegetation structure from imaging spectroscopy data. Of particular interest is Leaf Area Index (LAI), which is an informative, yet notoriously challenging parameter to efficiently measure in situ. While photosynthetically-active radiation (PAR) sensors have been validated for measuring crop LAI, there is limited literature on the efficacy of PAR-based LAI measurement in the forest environment. This study (i) validates PAR-based LAI measurement in forest environments, and (ii) proposes a suitable collection protocol, which balances efficiency with measurement variation, e.g., due to sun flecks and various-sized canopy gaps. A synthetic PAR sensor model was developed in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model and used to validate LAI measurement based on first-principles and explicitly-known leaf geometry. Simulated collection parameters were adjusted to empirically identify optimal collection protocols. These collection protocols were then validated in the field by correlating PAR-based LAI measurement to the normalized difference vegetation index (NDVI) extracted from the “classic” Airborne Visible Infrared Imaging Spectrometer (AVIRIS-C) data (R2 was 0.61). The results indicate that our proposed collecting protocol is suitable for measuring the LAI of sparse forest (LAI < 3–5 (m2/m2)). PMID:27428969

  1. Rassf5 and Ndr kinases regulate neuronal polarity through Par3 phosphorylation in a novel pathway.

    PubMed

    Yang, Rui; Kong, Eryan; Jin, Jing; Hergovich, Alexander; Püschel, Andreas W

    2014-08-15

    The morphology and polarized growth of cells depend on pathways that control the asymmetric distribution of regulatory factors. The evolutionarily conserved Ndr kinases play important roles in cell polarity and morphogenesis in yeast and invertebrates but it is unclear whether they perform a similar function in mammalian cells. Here, we analyze the function of mammalian Ndr1 and Ndr2 (also known as STK38 or STK38L, respectively) in the establishment of polarity in neurons. We show that they act downstream of the tumor suppressor Rassf5 and upstream of the polarity protein Par3 (also known as PARD3). Rassf5 and Ndr1 or Ndr2 are required during the polarization of hippocampal neurons to prevent the formation of supernumerary axons. Mechanistically, the Ndr kinases act by phosphorylating Par3 at Ser383 to inhibit its interaction with dynein, thereby polarizing the distribution of Par3 and reinforcing axon specification. Our results identify a novel Rassf5-Ndr-Par3 signaling cascade that regulates the transport of Par3 during the establishment of neuronal polarity. Their role in neuronal polarity suggests that Ndr kinases perform a conserved function as regulators of cell polarity.

  2. PAR-1 mediated apoptosis of breast cancer cells by V. cholerae hemagglutinin protease.

    PubMed

    Ray, Tanusree; Pal, Amit

    2016-05-01

    Bacterial toxins have emerged as promising agents in cancer treatment strategy. Hemagglutinin (HAP) protease secreted by Vibrio cholerae induced apoptosis in breast cancer cells and regresses tumor growth in mice model. The success of novel cancer therapies depends on their selectivity for cancer cells with limited toxicity for normal tissues. Increased expression of Protease Activated Receptor-1 (PAR-1) has been reported in different malignant cells. In this study we report that HAP induced activation and over expression of PAR-1 in breast cancer cells (EAC). Immunoprecipitation studies have shown that HAP specifically binds with PAR-1. HAP mediated activation of PAR-1 caused nuclear translocation of p50-p65 and the phosphorylation of p38 which triggered the activation of NFκB and MAP kinase signaling pathways. These signaling pathways enhanced the cellular ROS level in malignant cells that induced the intrinsic pathway of cell apoptosis. PAR-1 mediated apoptosis by HAP of malignant breast cells without effecting normal healthy cells in the same environment makes it a good therapeutic agent for treatment of cancer.

  3. Participatory action research (PAR) in middle school: opportunities, constraints, and key processes.

    PubMed

    Ozer, Emily J; Ritterman, Miranda L; Wanis, Maggie G

    2010-09-01

    Late childhood and early adolescence represent a critical transition in the developmental and academic trajectory of youth, a time in which there is an upsurge in academic disengagement and psychopathology. PAR projects that can promote youth's sense of meaningful engagement in school and a sense of efficacy and mattering can be particularly powerful given the challenges of this developmental stage. In the present study, we draw on data from our own collaborative implementation of PAR projects in secondary schools to consider two central questions: (1) How do features of middle school settings and the developmental characteristics of the youth promote or inhibit the processes, outcomes, and sustainability of the PAR endeavor? and (2) How can the broad principles and concepts of PAR be effectively translated into specific intervention activities in schools, both within and outside of the classroom? In particular, we discuss a participatory research project conducted with 6th and 7th graders at an urban middle school as a means of highlighting the opportunities, constraints, and lessons learned in our efforts to contribute to the high-quality implementation and evaluation of PAR in diverse urban public schools.

  4. uPAR induces epithelial–mesenchymal transition in hypoxic breast cancer cells

    PubMed Central

    Lester, Robin D.; Jo, Minji; Montel, Valérie; Takimoto, Shinako; Gonias, Steven L.

    2007-01-01

    Hypoxia activates genetic programs that facilitate cell survival; however, in cancer, it may promote invasion and metastasis. In this study, we show that breast cancer cells cultured in 1.0% O2 demonstrate changes consistent with epithelial–mesenchymal transition (EMT). Snail translocates to the nucleus, and E-cadherin is lost from plasma membranes. Vimentin expression, cell migration, Matrigel invasion, and collagen remodeling are increased. Hypoxia-induced EMT is accompanied by increased expression of the urokinase-type plasminogen activator receptor (uPAR) and activation of cell signaling factors downstream of uPAR, including Akt and Rac1. Glycogen synthase kinase-3β is phosphorylated, and Snail expression is increased. Hypoxia-induced EMT is blocked by uPAR gene silencing and mimicked by uPAR overexpression in normoxia. Antagonizing Rac1 or phosphatidylinositol 3-kinase also inhibits development of cellular properties associated with EMT in hypoxia. Breast cancer cells implanted on chick chorioallantoic membranes and treated with CoCl2, to model hypoxia, demonstrate increased dissemination. We conclude that in hypoxia, uPAR activates diverse cell signaling pathways that cooperatively induce EMT and may promote cancer metastasis. PMID:17664334

  5. Towards an Improved LAI Collection Protocol via Simulated and Field-Based PAR Sensing.

    PubMed

    Yao, Wei; Kelbe, David; Leeuwen, Martin van; Romanczyk, Paul; Aardt, Jan van

    2016-07-14

    In support of NASA's next-generation spectrometer-the Hyperspectral Infrared Imager (HyspIRI)-we are working towards assessing sub-pixel vegetation structure from imaging spectroscopy data. Of particular interest is Leaf Area Index (LAI), which is an informative, yet notoriously challenging parameter to efficiently measure in situ. While photosynthetically-active radiation (PAR) sensors have been validated for measuring crop LAI, there is limited literature on the efficacy of PAR-based LAI measurement in the forest environment. This study (i) validates PAR-based LAI measurement in forest environments, and (ii) proposes a suitable collection protocol, which balances efficiency with measurement variation, e.g., due to sun flecks and various-sized canopy gaps. A synthetic PAR sensor model was developed in the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model and used to validate LAI measurement based on first-principles and explicitly-known leaf geometry. Simulated collection parameters were adjusted to empirically identify optimal collection protocols. These collection protocols were then validated in the field by correlating PAR-based LAI measurement to the normalized difference vegetation index (NDVI) extracted from the "classic" Airborne Visible Infrared Imaging Spectrometer (AVIRIS-C) data ( R 2 was 0.61). The results indicate that our proposed collecting protocol is suitable for measuring the LAI of sparse forest (LAI < 3-5 ( m 2 / m 2 )).

  6. Participatory Action Research (PAR) in Middle School: Opportunities, Constraints, and Key Processes

    PubMed Central

    Ritterman, Miranda L.; Wanis, Maggie G.

    2010-01-01

    Late childhood and early adolescence represent a critical transition in the developmental and academic trajectory of youth, a time in which there is an upsurge in academic disengagement and psychopathology. PAR projects that can promote youth’s sense of meaningful engagement in school and a sense of efficacy and mattering can be particularly powerful given the challenges of this developmental stage. In the present study, we draw on data from our own collaborative implementation of PAR projects in secondary schools to consider two central questions: (1) How do features of middle school settings and the developmental characteristics of the youth promote or inhibit the processes, outcomes, and sustainability of the PAR endeavor? and (2) How can the broad principles and concepts of PAR be effectively translated into specific intervention activities in schools, both within and outside of the classroom? In particular, we discuss a participatory research project conducted with 6th and 7th graders at an urban middle school as a means of highlighting the opportunities, constraints, and lessons learned in our efforts to contribute to the high-quality implementation and evaluation of PAR in diverse urban public schools. PMID:20676754

  7. Étude par microscopie acoustique de couches minces de Ag2S déposées par spray

    NASA Astrophysics Data System (ADS)

    Amlouk, M.; Brunet, N.; Cros, B.; Belgacem, S.; Barjon, D.

    1997-09-01

    Silver sulfide Ag2S thin films have been prepared on pyrex glass substrates by the spray pyrolysis technique at 250 °C. We have analyzed by acoustic microscopy and particularly by acoustic signature V(z) these films with various thickness (0.4 2 μm). The acoustic signature, performed at 50, 130 and 570 MHz allow us to reach elastic properties of Ag2S material and specially Young modulus. Its value, of the order of 180 GPa, is consistent with the relative low linkage of Ag^+ in the structure and the character of fast-ion conductor of Ag2S. Besides elastic properties and using MEB and AFM investigations, we have shown that the V(z) signature gives valuable information about the bulk defects in the material. Finally, the experimental results have been discussed related to the dispersion curves of velocity of the first mode of Ag2S/pyrex system. Des couches minces de sulfure d'argent Ag2S sont préparées sur substrat de pyrex, à la température de 250 °C, par la technique de pulvérisation chimique réactive en phase liquide ou “spray". Ces dépôts, d'épaisseur variable (0,4 2 μm), sont analysés par microscopie acoustique et, plus particulièrement, par la méthode de relevé de la signature acoustique V(z). Cette signature, effectuée à différentes fréquences (50, 130, 570 MHz), a permis de caractériser les propriétés élastiques du matériau Ag2S. La valeur du module d'Young, de l'ordre de 180 GPa, est en accord avec la faible cohésion de la liaison Ag-S et le caractère de conducteur ionique rapide de Ag2S. Les observations par MEB et AFM permettent d'expliquer l'allure des courbes V(z) par les défauts de compacité liés à la méthode de préparation. Les résultats expérimentaux sont discutés en liaison avec la courbe de dispersion de vitesses du premier mode du système Ag2S/pyrex.

  8. First record of the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), in Pará nut, Bertholletia excelsa (Lecythidaceae).

    PubMed

    Gumier-Costa, Fabiano

    2009-01-01

    We report the occurrence of Hypothenemus hampei (Ferrari) attacking Pará nuts stored in the southeast of Para state. The coffee berry borer successfully colonized and reproduced using Pará nuts as a food source. Based on this observation, the Pará nuts can be used as an alternative food source in rearing the coffee berry borer. Also, attention should be brought to need of proper storage of these nuts to avoid infestation by this pest.

  9. Endothelial progenitor cell-dependent angiogenesis requires localization of the full-length form of uPAR in caveolae.

    PubMed

    Margheri, Francesca; Chillà, Anastasia; Laurenzana, Anna; Serratì, Simona; Mazzanti, Benedetta; Saccardi, Riccardo; Santosuosso, Michela; Danza, Giovanna; Sturli, Niccolò; Rosati, Fabiana; Magnelli, Lucia; Papucci, Laura; Calorini, Lido; Bianchini, Francesca; Del Rosso, Mario; Fibbi, Gabriella

    2011-09-29

    Endothelial urokinase-type plasminogen activator receptor (uPAR) is thought to provide a regulatory mechanism in angiogenesis. Here we studied the proangiogenic role of uPAR in endothelial colony-forming cells (ECFCs), a cell population identified in human umbilical blood that embodies all of the properties of an endothelial progenitor cell matched with a high proliferative rate. By using caveolae-disrupting agents and by caveolin-1 silencing, we have shown that the angiogenic properties of ECFCs depend on caveolae integrity and on the presence of full-length uPAR in such specialized membrane invaginations. Inhibition of uPAR expression by antisense oligonucleotides promoted caveolae disruption, suggesting that uPAR is an inducer of caveolae organization. Vascular endothelial growth factor (VEGF) promoted accumulation of uPAR in ECFC caveolae in its undegraded form. We also demonstrated that VEGF-dependent ERK phosphorylation required integrity of caveolae as well as caveolar uPAR expression. VEGF activity depends on inhibition of ECFC MMP12 production, which results in impairment of MMP12-dependent uPAR truncation. Further, MMP12 overexpression in ECFC inhibited vascularization in vitro and in vivo. Our data suggest that intratumor homing of ECFCs suitably engineered to overexpress MMP12 could have the chance to control uPAR-dependent activities required for tumor angiogenesis and malignant cells spreading.

  10. Transient early neurotrophin release and delayed inflammatory cytokine release by microglia in response to PAR-2 stimulation.

    PubMed

    Chen, Chen-Wen; Chen, Qian-Bo; Ouyang, Qing; Sun, Ji-Hu; Liu, Fang-Ting; Song, Dian-Wen; Yuan, Hong-Bin

    2012-06-25

    Activated microglia exerts both beneficial and deleterious effects on neurons, but the signaling mechanism controlling these distinct responses remain unclear. We demonstrated that treatment of microglial cultures with the PAR-2 agonist, 2-Furoyl-LIGRLO-NH2, evoked early transient release of BDNF, while sustained PAR-2 stimulation evoked the delayed release of inflammatory cytokines (IL-1 β and TNF-α) and nitric oxide. Culture medium harvested during the early phase (at 1 h) of microglial activation induced by 2-Furoyl-LIGRLO-NH2 (microglial conditioned medium, MCM) had no deleterious effects on cultured neurons, while MCM harvested during the late phase (at 72 h) promoted DNA fragmentation and apoptosis as indicated by TUNEL and annexin/PI staining. Blockade of PAR-1 during the early phase of PAR-2 stimulation enhanced BDNF release (by 11%, small but significant) while a PAR-1 agonist added during the late phase (24 h after 2-Furoyl-LIGRLO-NH2 addition) suppressed the release of cytokines and NO. The neuroprotective and neurotoxic effects of activated microglial exhibit distinct temporal profiles that are regulated by PAR-1 and PAR-2 stimulation. It may be possible to facilitate neuronal recovery and repair by appropriately timed stimulation and inhibition of microglial PAR-1 and PAR-2 receptors.

  11. Participatory action research (PAR): an approach for improving black women's health in rural and remote communities.

    PubMed

    Etowa, Josephine B; Bernard, Wanda Thomas; Oyinsan, Bunmi; Clow, Barbara

    2007-10-01

    Women are among the most disadvantaged members of any community, and they tend to be at greatest risk of illness. Black women are particularly vulnerable and more prone than White women to illnesses associated with social and economic deprivation, including heart disease and diabetes. They utilize preventive health services less often, and when they fall ill, the health of their families and communities typically suffers as well. This article discusses the process of doing innovative participatory action research (PAR) in southwest Nova Scotia Black communities. The effort resulted in the generation of a database, community action, and interdisciplinary analysis of the intersecting inequities that compromise the health and health care of African Canadian women, their families, and their communities. This particular research effort serves as a case study for explicating the key tenets of PAR and the barriers to and contradictions in implementing PAR in a community-academic collaborative research project.

  12. Potential Ecological Effects of Contaminants in the Exposed Par Pond Sediments

    SciTech Connect

    Paller, M.H.; Wike, L.D.

    1996-08-01

    Sediment and small mammal samples were collected from the exposed sediments of Par Pond in early 1995, shortly before the reservoir was refilled after a 4-year drawdown. Sampling was confined to elevations between 58 and 61 meters (190 and 200 feet) above mean sea level, which includes the sediments likely to be exposed if the Par Pond water level is permitted to fluctuate naturally. Both soil and small mammal samples were analyzed for a number of radionuclides and metals. Some of the soil samples were also analyzed for organic contaminants. The objective of the study was to determine if contaminant levels in the Par Pond sediments were high enough to cause deleterious ecological effects.

  13. The Par complex and integrins direct asymmetric cell division in adult intestinal stem cells.

    PubMed

    Goulas, Spyros; Conder, Ryan; Knoblich, Juergen A

    2012-10-05

    The adult Drosophila midgut is maintained by intestinal stem cells (ISCs) that generate both self-renewing and differentiating daughter cells. How this asymmetry is generated is currently unclear. Here, we demonstrate that asymmetric ISC division is established by a unique combination of extracellular and intracellular polarity mechanisms. We show that Integrin-dependent adhesion to the basement membrane induces cell-intrinsic polarity and results in the asymmetric segregation of the Par proteins Par-3, Par-6, and aPKC into the apical daughter cell. Cell-specific knockdown and overexpression experiments suggest that increased activity of aPKC enhances Delta/Notch signaling in one of the two daughter cells to induce terminal differentiation. Perturbing this mechanism or altering the orientation of ISC division results in the formation of intestinal tumors. Our data indicate that mechanisms for intrinsically asymmetric cell division can be adapted to allow for the flexibility in lineage decisions that is required in adult stem cells.

  14. Peptidomics of the pars intercerebralis-corpus cardiacum complex of the migratory locust, Locusta migratoria.

    PubMed

    Clynen, E; Baggerman, G; Veelaert, D; Cerstiaens, A; Van der Horst, D; Harthoorn, L; Derua, R; Waelkens, E; De Loof, A; Schoofs, L

    2001-04-01

    The pars intercerebralis-corpora cardiaca system (PI-CC) of insects is the endocrinological equivalent of the hypothalamus-pituitary system of vertebrates. Peptide profiles of the pars intercerebralis and the corpora cardiaca were characterized using simple sampling protocols in combination with MALDI-TOF and electrospray ionization double quadrupole time of flight (ESI-Qq-TOF) mass spectrometric technologies. The results were compared with earlier results of conventional sequencing methods and immunocytochemical methods. In addition to many known peptides, several m/z signals corresponding to putative novel peptides were observed in the corpora cardiaca and/or pars intercerebralis. Furthermore, for a number of peptides evidence was provided about their localization and MALDI-TOF analysis of the released material from the corpora cardiaca yielded information on the hormonal status of particular brain peptides.

  15. Parádsasvárite, a new member of the malachite-rosasite group from Parádsasvár, Mátra Mountains, Hungary

    NASA Astrophysics Data System (ADS)

    Fehér, Béla; Szakáll, Sándor; Zajzon, Norbert; Mihály, Judith

    2015-08-01

    Parádsasvárite (IMA No. 2012-077) was found in the Nagy-Lápafő area, Parádsasvár, Mátra Mountains, Hungary. It forms pale beige, globular aggregates up to 0.2 mm in diameter on calcite. Associated secondary minerals are smithsonite, hemimorphite, hydrozincite, aurichalcite and rosasite. The mineral was formed as an alteration product of sphalerite and chalcopyrite in a carbonate-rich environment. Parádsasvárite is translucent with a weakly vitreous, dull or silky lustre and white streak. Its Mohs hardness is about 2-3, cleavage and parting were not observed. It is brittle; the fracture is finely fibrous. Average of nine electron-microprobe analyses gave ZnO 58.08, CuO 12.60, PbO 1.27, CO2 (calc.) 19.50, H2O (calc.) 7.94, total 99.39 wt.%, corresponding to the empirical formula (Zn0.62Cu0.36Pb0.01)Σ0.99Zn1.00(CO3)(OH)2. The seven strongest lines in the X-ray powder diffraction pattern are [dhkl in Å (Iobs %, hkl)] 6.054 (67, 200), 5.085 (100, 210), 3.703 (87, 310 and 220), 3.021 (25, 400 and 130), 2.971 (25, -211 and 001), 2.603 (62, -221) and 2.539 (36, 420). According to its X-ray powder diffraction data and chemical formula, parádsasvárite belongs to the malachite-rosasite group and it is isostructural with rosasite. It is monoclinic, space group P21/ a, a = 12.92(1), b = 9.372(7), c = 3.159(4) Å, β = 110.4(1)°, V = 358.5(5) Å3, Z = 4.

  16. Factor Xa stimulates fibroblast procollagen production, proliferation, and calcium signaling via PAR{sub 1} activation

    SciTech Connect

    Blanc-Brude, Olivier P. . E-mail: olivier.blanc-brude@larib.inserm.fr; Archer, Fabienne; Leoni, Patricia; Derian, Claudia; Bolsover, Steven; Laurent, Geoffrey J.; Chambers, Rachel C.

    2005-03-10

    Fibroblast proliferation and procollagen production are central features of tissue repair and fibrosis. In addition to its role in blood clotting, the coagulation cascade proteinase thrombin can contribute to tissue repair by stimulating fibroblasts via proteolytic activation of proteinase-activated receptor-1 (PAR{sub 1}). During hemostasis, the coagulation cascade proteinase factor X is converted into factor Xa. We have previously shown that factor Xa upregulates fibroblast proliferation via production of autocrine PDGF. In this study, we further examined the effects of factor Xa on fibroblast function and aimed to identify its signaling receptor. We showed that factor Xa stimulates procollagen promoter activity and protein production by human and mouse fibroblasts. This effect was independent of PDGF and thrombin production, but dependent on factor Xa proteolytic activity. We also showed that PAR{sub 1}-deficient mouse fibroblasts did not upregulate procollagen production, mobilize cytosolic calcium, or proliferate in response to factor Xa. Desensitization techniques and PAR{sub 1}-specific agonists and inhibitors were used to demonstrate that PAR{sub 1} mediates factor Xa signaling in human fibroblasts. This is the first report that factor Xa stimulates extracellular matrix production. In contrast with endothelial cells and vascular smooth muscle cells, fibroblasts appear to be the only cell type in which the effects of factor Xa are mediated mainly via PAR{sub 1} and not PAR{sub 2}. These findings are critical for our understanding of tissue repair and fibrotic mechanisms, and for the design of novel approaches to inhibit the profibrotic effects of the coagulation cascade without compromising blood hemostasis.

  17. Linking the fPAR, forest albedo and biomass in the northern biomes of Europe

    NASA Astrophysics Data System (ADS)

    Lukeš, Petr; Stenberg, Pauline; Manninen, Terhikki; Rautiainen, Miina; Mõttus, Matti

    2014-05-01

    Land surface albedo and the fraction of photosynthetically active radiation (fPAR) absorbed by plant canopies are two of the essential climate variables controlling the planetary radiative energy budget. Albedo is directly related to the energy exchange between land and the atmosphere as it is the reflectivity of the surface - the higher the albedo, the more incoming solar radiation is reflected and the less absorbed by the surface. The fPAR is related to plant productivity, quantifying the amount of absorbed light available for photosynthesis. It is a key parameter in the modelling of net primary production (NPP) of terrestrial ecosystems. Global climate scenarios are very sensitive to albedo and fPAR estimates, and thus, the effect of changes in canopy structure and density (biomass) on these two variables needs to be quantified reliably. Both parameters are routinely retrieved from current Earth Observation sensors using specialized algorithms. To date, these satellite products have not been linked to extensive forest inventory data sets due to the lack of ground reference data. Data availability for Finland has significantly improved in December 2012, when National Forest Inventory (NFI) data became freely available to the public. The dataset covers the geographical area of Finland (26.1 million hectares) at a spatial resolution of 20 meters including several forest structural variables. In this study, we use the NFI data to study the links between forest albedo, fPAR and forest structure and density during the green vegetation season. More specifically, we investigated the seasonal trends in fPAR and albedo of different spectral regions of northern forests. Empirical relationships between forest albedo, fPAR and total aboveground biomass were established for selected days within the vegetation growing period and across a latitudinal transect of Finland.

  18. Comparing the 7-Day PAR with a Triaxial Accelerometer for Measuring Time in Exercise

    PubMed Central

    Sloane, Richard; Snyder, Denise Clutter; Demark-Wahnefried, Wendy; Lobach, David; Kraus, William E.

    2009-01-01

    Purpose The primary study aim was to evaluate associations of estimated weekly minutes of moderate-to-vigorous intensity exercise from self-reports of the telephone-administered 7-Day Physical Activity Recall (PAR) with data captured by the RT3 triaxial accelerometer. Methods This investigation was undertaken as part of the FRESH START study, a randomized clinical trial that tested an iteratively-tailored diet and exercise mailed print intervention among newly diagnosed breast and prostate cancer survivors. A convenience sample of 139 medically-eligible subjects living within a 60-mile radius of the study center provided both 7-Day PAR and accelerometer data at enrollment. Ultimately n=115 substudy subjects were found eligible for the FRESH START study and randomized to one of two study treatment arms. Follow-up assessments at Year 1 (n=103) and Year 2 (n=99) provided both the 7-Day PAR and accelerometer data. Results There was moderate agreement between the 7-Day PAR and the accelerometer with longitudinal serial correlation coefficients of .54 (baseline), .24 (Year 1) and .53 (Year 2), all P-values < .01, though the accelerometer estimates for weekly time in moderate-to-vigorous physical activity were much higher than those of the 7-Day PAR at all time points. The two methods were poorly correlated in assessing sensitivity to change from baseline to Year 1 (rho=.11, P=.30). Using mixed models repeated measures analysis, both methods exhibited similar non-significant treatment arm X time interaction P-values (7-Day PAR=.22, accelerometer=.23). Conclusions The correlations for three serial time points were in agreement with findings of other studies that compared self-reported time in exercise with physical activity captured by accelerometry. However, these methods capture somewhat different dimensions of physical activity and provide differing estimates of change over time. PMID:19461530

  19. Function inferences from a molecular structural model of bacterial ParE toxin

    PubMed Central

    Barbosa, Luiz Carlos Bertucci; Garrido, Saulo Santesso; Garcia, Anderson; Delfino, Davi Barbosa; Marchetto, Reinaldo

    2010-01-01

    Toxin-antitoxin (TA) systems contribute to plasmid stability by a mechanism that relies on the differential stabilities of the toxin and antitoxin proteins and leads to the killing of daughter bacteria that did not receive a plasmid copy at the cell division. ParE is the toxic component of a TA system that constitutes along with RelE an important class of bacterial toxin called RelE/ParE superfamily. For ParE toxin, no crystallographic structure is available so far and rare in vitro studies demonstrated that the target of toxin activity is E. coli DNA gyrase. Here, a 3D Model for E. coli ParE toxin by molecular homology modeling was built using MODELLER, a program for comparative modeling. The Model was energy minimized by CHARMM and validated using PROCHECK and VERIFY3D programs. Resulting Ramachandran plot analysis it was found that the portion residues failing into the most favored and allowed regions was 96.8%. Structural similarity search employing DALI server showed as the best matches RelE and YoeB families. The Model also showed similarities with other microbial ribonucleases but in a small score. A possible homologous deep cleft active site was identified in the Model using CASTp program. Additional studies to investigate the nuclease activity in members of ParE family as well as to confirm the inhibitory replication activity are needed. The predicted Model allows initial inferences about the unexplored 3D structure of the ParE toxin and may be further used in rational design of molecules for structure­function studies. PMID:20975905

  20. K-Area and Par Pond Sewage Sludge Application Sites groundwater monitoring reports, second quarter 1992

    SciTech Connect

    Not Available

    1992-10-01

    During second quarter 1992, the three wells at the K-Area Sewage Sludge Application Site (KSS wells) and the three wells at the Par Pond Sewage Sludge Application Site (PSS wells) were sampled for analyses required each quarter or annually by South Carolina Department of Health and Environmental Control Construction Permit 13, 173. This report includes the results of those analyses. None of the analyzed constituents exceeded the Primary Drinking Water Standard or the Savannah River Site Flag 2 criteria at either the K-Area Sewage Sludge Application Site or the Par Pond Sewage Sludge Application Site.

  1. Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

    PubMed

    Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

    2015-04-20

    During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs.

  2. Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex.

    PubMed

    Roll, Patrice; Vernes, Sonja C; Bruneau, Nadine; Cillario, Jennifer; Ponsole-Lenfant, Magali; Massacrier, Annick; Rudolf, Gabrielle; Khalife, Manal; Hirsch, Edouard; Fisher, Simon E; Szepetowski, Pierre

    2010-12-15

    It is a challenge to identify the molecular networks contributing to the neural basis of human speech. Mutations in transcription factor FOXP2 cause difficulties mastering fluent speech (developmental verbal dyspraxia, DVD), whereas mutations of sushi-repeat protein SRPX2 lead to epilepsy of the rolandic (sylvian) speech areas, with DVD or with bilateral perisylvian polymicrogyria. Pathophysiological mechanisms driven by SRPX2 involve modified interaction with the plasminogen activator receptor (uPAR). Independent chromatin-immunoprecipitation microarray screening has identified the uPAR gene promoter as a potential target site bound by FOXP2. Here, we directly tested for the existence of a transcriptional regulatory network between human FOXP2 and the SRPX2/uPAR complex. In silico searches followed by gel retardation assays identified specific efficient FOXP2-binding sites in each of the promoter regions of SRPX2 and uPAR. In FOXP2-transfected cells, significant decreases were observed in the amounts of both SRPX2 (43.6%) and uPAR (38.6%) native transcripts. Luciferase reporter assays demonstrated that FOXP2 expression yielded a marked inhibition of SRPX2 (80.2%) and uPAR (77.5%) promoter activity. A mutant FOXP2 that causes DVD (p.R553H) failed to bind to SRPX2 and uPAR target sites and showed impaired down-regulation of SRPX2 and uPAR promoter activity. In a patient with polymicrogyria of the left rolandic operculum, a novel FOXP2 mutation (p.M406T) was found in the leucine-zipper (dimerization) domain. p.M406T partially impaired the FOXP2 regulation of SRPX2 promoter activity, whereas that of the uPAR promoter remained unchanged. Together with recently described FOXP2-CNTNAP2 and SRPX2/uPAR links, the FOXP2-SRPX2/uPAR network provides exciting insights into molecular pathways underlying speech-related disorders.

  3. AP-3 regulates PAR1 ubiquitin-independent MVB/lysosomal sorting via an ALIX-mediated pathway

    PubMed Central

    Dores, Michael R.; Paing, May M.; Lin, Huilan; Montagne, William A.; Marchese, Adriano; Trejo, JoAnn

    2012-01-01

    The sorting of signaling receptors within the endocytic system is important for appropriate cellular responses. After activation, receptors are trafficked to early endosomes and either recycled or sorted to lysosomes and degraded. Most receptors trafficked to lysosomes are modified with ubiquitin and recruited into an endosomal subdomain enriched in hepatocyte growth factor–regulated tyrosine kinase substrate (HRS), a ubiquitin-binding component of the endosomal-sorting complex required for transport (ESCRT) machinery, and then sorted into intraluminal vesicles (ILVs) of multivesicular bodies (MVBs)/lysosomes. However, not all receptors use ubiquitin or the canonical ESCRT machinery to sort to MVBs/lysosomes. This is exemplified by protease-activated receptor-1 (PAR1), a G protein–coupled receptor for thrombin, which sorts to lysosomes independent of ubiquitination and HRS. We recently showed that the adaptor protein ALIX binds to PAR1, recruits ESCRT-III, and mediates receptor sorting to ILVs of MVBs. However, the mechanism that initiates PAR1 sorting at the early endosome is not known. We now report that the adaptor protein complex-3 (AP-3) regulates PAR1 ubiquitin-independent sorting to MVBs through an ALIX-dependent pathway. AP-3 binds to a PAR1 cytoplasmic tail–localized tyrosine-based motif and mediates PAR1 lysosomal degradation independent of ubiquitination. Moreover, AP-3 facilitates PAR1 interaction with ALIX, suggesting that AP-3 functions before PAR1 engagement of ALIX and MVB/lysosomal sorting. PMID:22833563

  4. The Rac-GAP Bcr is a novel regulator of the Par complex that controls cell polarity

    PubMed Central

    Narayanan, Anjana S.; Reyes, Steve B.; Um, Kyongmi; McCarty, Joseph H.; Tolias, Kimberley F.

    2013-01-01

    Cell polarization is essential for many biological processes, including directed cell migration, and loss of polarity contributes to pathological conditions such as cancer. The Par complex (Par3, Par6, and PKCζ) controls cell polarity in part by recruiting the Rac-specific guanine nucleotide exchange factor T-lymphoma invasion and metastasis 1 (Tiam1) to specialized cellular sites, where Tiam1 promotes local Rac1 activation and cytoskeletal remodeling. However, the mechanisms that restrict Par-Tiam1 complex activity to the leading edge to maintain cell polarity during migration remain unclear. We identify the Rac-specific GTPase-activating protein (GAP) breakpoint cluster region protein (Bcr) as a novel regulator of the Par-Tiam1 complex. We show that Bcr interacts with members of the Par complex and inhibits both Rac1 and PKCζ signaling. Loss of Bcr results in faster, more random migration and striking polarity defects in astrocytes. These polarity defects are rescued by reducing PKCζ activity or by expressing full-length Bcr, but not an N-terminal deletion mutant or the homologous Rac-GAP, Abr, both of which fail to associate with the Par complex. These results demonstrate that Bcr is an integral member of the Par-Tiam1 complex that controls polarized cell migration by locally restricting both Rac1 and PKCζ function. PMID:24152735

  5. Soluble urokinase receptor (suPAR) predicts microalbuminuria in patients at risk for type 2 diabetes mellitus

    PubMed Central

    Guthoff, Martina; Wagner, Robert; Randrianarisoa, Elko; Hatziagelaki, Erifili; Peter, Andreas; Häring, Hans-Ulrich; Fritsche, Andreas; Heyne, Nils

    2017-01-01

    Early identification of patients at risk of developing diabetic nephropathy is essential. Elevated serum concentrations of soluble urokinase receptor (suPAR) associate with diabetes mellitus and predict onset and loss of renal function in chronic kidney disease. We hypothesize, that suPAR may be an early risk indicator for diabetic nephropathy, preceding microalbuminuria. The relationship of baseline suPAR and incident microalbuminuria was assessed in a prospective long-term cohort of subjects at increased risk for type 2 diabetes (TULIP, n = 258). Association with albuminuria at later stages of disease was studied in a cross-sectional cohort with manifest type 2 diabetes (ICEPHA, n = 266). A higher baseline suPAR was associated with an increased risk of new-onset microalbuminuria in subjects at risk for type 2 diabetes (hazard ratio 5.3 (95% CI 1.1–25.2, p = 0.03) for the highest vs. lowest suPAR quartile). The proportion of subjects with prediabetes at the end of observation was higher in subjects with new-onset microalbuminuria. suPAR consistently correlated with albuminuria in a separate cohort with manifest type 2 diabetes. Elevated baseline suPAR concentrations independently associate with new-onset microalbuminuria in subjects at increased risk of developing type 2 diabetes. suPAR may hence allow for earlier risk stratification than microalbuminuria. PMID:28091558

  6. A Type Ib ParB Protein Involved in Plasmid Partitioning in a Gram-Positive Bacterium▿

    PubMed Central

    Yin, Ping; Li, Tai-Yuan; Xie, Mao-Hua; Jiang, Lina; Zhang, Yi

    2006-01-01

    Our current understanding of segregation of prokaryotic plasmids has been derived mainly from the study of the gram-negative bacterial plasmids. We previously reported a replicon of the cryptic plasmid from a gram-positive bacterium, Leifsonia xyli subsp. cynodontis. The replicon contains a putative plasmid partition cassette including a Walker-type ATPase followed by open reading frame 4 without sequence homologue. Here we reported that the orf4 gene was essential for maintaining the plasmid stability in L. xyli subsp. cynodontis. Furthermore, the purified orf4 protein specifically and cooperatively bound to direct repeat sequences located upstream of the parA gene in vitro, indicating that orf4 is a parB gene and that the direct repeat DNA sequences constitute a partition site, parS. The location of parS and the features of ParA and ParB proteins suggest that this plasmid partition cassette belongs to type Ib, representing the first type Ib cassette identified from a gram-positive bacterial plasmid. PMID:16997970

  7. Urokinase-type plasminogen activator receptor (uPAR) as a promising new imaging target: potential clinical applications

    PubMed Central

    Persson, Morten; Kjaer, Andreas

    2013-01-01

    Urokinase-type plasminogen activator receptor (uPAR) has been shown to be of special importance during cancer invasion and metastasis. However, currently, tissue samples are needed for measurement of uPAR expression limiting the potential as a clinical routine. Therefore, non-invasive methods are needed. In line with this, uPAR has recently been identified as a very promising imaging target candidate. uPAR consists of three domains attached to the cell membrane via a glycosylphosphatidylinositol (GPI) anchor and binds it natural ligand uPA with high affinity to localize plasminogen activation at the cell surface. Due to the importance of uPAR in cancer invasion and metastasis, a number of high-affinity ligands have been identified during the last decades. These ligands have recently been used as starting point for the development of a number of ligands for imaging of uPAR using various imaging modalities such as optical imaging, magnetic resonance imaging, single photon emission computer tomography (SPECT) and positron emission topography (PET). In this review, we will discuss recent advances in the development of uPAR-targeted imaging ligands according to imaging modality. In addition, we will discuss the potential future clinical application for uPAR imaging as a new imaging biomarker. PMID:23701192

  8. Soluble urokinase receptor (suPAR) predicts microalbuminuria in patients at risk for type 2 diabetes mellitus.

    PubMed

    Guthoff, Martina; Wagner, Robert; Randrianarisoa, Elko; Hatziagelaki, Erifili; Peter, Andreas; Häring, Hans-Ulrich; Fritsche, Andreas; Heyne, Nils

    2017-01-16

    Early identification of patients at risk of developing diabetic nephropathy is essential. Elevated serum concentrations of soluble urokinase receptor (suPAR) associate with diabetes mellitus and predict onset and loss of renal function in chronic kidney disease. We hypothesize, that suPAR may be an early risk indicator for diabetic nephropathy, preceding microalbuminuria. The relationship of baseline suPAR and incident microalbuminuria was assessed in a prospective long-term cohort of subjects at increased risk for type 2 diabetes (TULIP, n = 258). Association with albuminuria at later stages of disease was studied in a cross-sectional cohort with manifest type 2 diabetes (ICEPHA, n = 266). A higher baseline suPAR was associated with an increased risk of new-onset microalbuminuria in subjects at risk for type 2 diabetes (hazard ratio 5.3 (95% CI 1.1-25.2, p = 0.03) for the highest vs. lowest suPAR quartile). The proportion of subjects with prediabetes at the end of observation was higher in subjects with new-onset microalbuminuria. suPAR consistently correlated with albuminuria in a separate cohort with manifest type 2 diabetes. Elevated baseline suPAR concentrations independently associate with new-onset microalbuminuria in subjects at increased risk of developing type 2 diabetes. suPAR may hence allow for earlier risk stratification than microalbuminuria.

  9. TGFβ upregulates PAR-1 expression and signalling responses in A549 lung adenocarcinoma cells

    PubMed Central

    Smoktunowicz, Natalia; Platé, Manuela; Stern, Alejandro Ortiz; D'Antongiovanni, Vanessa; Robinson, Eifion; Chudasama, Vijay; Caddick, Stephen; Scotton, Chris J.; Jarai, Gabor; Chambers, Rachel C.

    2016-01-01

    The major high-affinity thrombin receptor, proteinase activated receptor-1 (PAR-1) is expressed at low levels by the normal epithelium but is upregulated in many types of cancer, including lung cancer. The thrombin-PAR-1 signalling axis contributes to the activation of latent TGFβ in response to tissue injury via an αvβ6 integrin-mediated mechanism. TGFβ is a pleiotropic cytokine that acts as a tumour suppressor in normal and dysplastic cells but switches into a tumour promoter in advanced tumours. In this study we demonstrate that TGFβ is a positive regulator of PAR-1 expression in A549 lung adenocarcinoma cells, which in turn increases the sensitivity of these cells to thrombin signalling. We further demonstrate that this effect is Smad3-, ERK1/2- and Sp1-dependent. We also show that TGFβ-mediated PAR-1 upregulation is accompanied by increased expression of integrin αv and β6 subunits. Finally, TGFβ pre-stimulation promotes increased migratory potential of A549 to thrombin. These data have important implications for our understanding of the interplay between coagulation and TGFβ signalling responses in lung cancer. PMID:27566553

  10. UTILITY OF A WIDE SPECTRUM LIGHT METER AS AN UNDERWATER SENSOR OF PHOTOSYNTHETICALLY ACTIVE RADIATION (PAR)

    EPA Science Inventory

    The strong attenuation of infra red wavelengths (>700 nm) in coastal waters is suggestive that some instruments with broad spectral responses might be useful, inexpensive substitutes for PAR sensors in studies of estuarine plant dynamics. Wide spectrum (350-1100 nm) light intensi...

  11. Appropriately Targeting Group Interventions for Academic Success Adopting the Clinical Model and PAR Profiles

    ERIC Educational Resources Information Center

    Johnson, Craig W.; Johnson, Ronald; Steigman, Michael; Odo, Chioma; Vijayan, Suvendra; Tata, Devadatta V.

    2016-01-01

    Prevalence of academic risk (PAR) group profiles provide data enabling empirically based group-specialized prescriptions for targeted academic success interventions to increase student retention, completion, and graduation rates, while improving allocation of institutional resources. Postsecondary student attrition engenders student debt,…

  12. Dengue epidemic in Belém, Pará, Brazil, 1996-97.

    PubMed Central

    Trravassos da Rosa, A. P.; Vasconcelos, P. F.; Travassos Da Rosa, E. S.; Rodrigues, S. G.; Mondet, B.; Cruz, A. C.; Sousa, M. R.; Travassos Da Rosa, J. F.

    2000-01-01

    We describe clinical and epidemiologic findings during the first epidemic of dengue fever in Belém, Pará State, Brazil, in 1996-97. Of 40,237 serum samples, 17,440 (43%) were positive for dengue by virus isolation or serologic testing. No hemorrhagic cases or deaths were reported. Mycobacterium tuberculosis PMID:10827121

  13. An Overview of the Peer Assessment Rating (par) Index for Primary Dental Care Practitioners.

    PubMed

    Green, James Ij

    2016-11-01

    The Peer Assessment Rating (PAR) index is a valid and reliable measure of orthodontic treatment outcome and is the most widely accepted such index. Assessing outcomes with the PAR index requires the examination of pre-treatment and post-treatment orthodontic study models. Beginning with the pre-treatment models, a score is given to each feature that deviates from an ideal occlusion (all anatomical contact points adjacent, good interdigitation between posterior teeth and non-excessive overjet/overbite), the scores are then added together to give a total that represents the severity of the malocclusion. The process is then repeated with the post-treatment models. The difference between the pre-treatment and the post-treatment scores reflects the improvement that has taken place during treatment. A score of zero represents an ideal occlusion and in general the higher the score, the more extensive the malocclusion. It is currently a condition of the NHS orthodontic contract for providers to monitor a proportion of their cases using the PAR index. This paper aims to provide primary dental care practitioners with an overview of the PAR index and should provide a useful guide for those wishing to seek calibration in the use of the index.

  14. Leuconychie transversale induite par la manucurie: y a-t-il un apport de la dermoscopie?

    PubMed Central

    Gallouj, Salim; Mernissi, Fatima Zahra

    2014-01-01

    La leuconychie transversale induite par la manucurie est une leuconychie secondaire au microtraumatisme transmis à la matrice unguéale. Nous rapportant une observation où la dermoscopie avait un intérêt considérable pour l'orientation diagnostic. PMID:25368728

  15. Measurement of the topography of human cadaver lenses using the PAR corneal topography system

    NASA Astrophysics Data System (ADS)

    Fernandez, Viviana; Manns, Fabrice; Zipper, Stanley; Sandadi, Samith; Hamaoui, Marie; Tahi, Hassan; Ho, Arthur; Parel, Jean-Marie A.

    2001-06-01

    To measure the radius of curvature and asphericity of the anterior and posterior surfaces of crystalline lenses of human Eye-Bank eyes using the PAR Corneal Topography System. The measured values will be used in an optical model of the eye for lens refilling procedures.

  16. CALiPER Report 20.3: Robustness of LED PAR38 Lamps

    SciTech Connect

    none,

    2014-12-30

    A small sample of each of the CALiPER Application Summary Report 20 PAR38 lamp types underwent stress testing that included substantial temperature and humidity changes, electrical variation, and vibration. The results do not directly address expected lifetime, but can be compared with one another, as well as with benchmark conventional products, to assess the relative robustness of the product designs.

  17. Cortical PAR polarity proteins promote robust cytokinesis during asymmetric cell division

    PubMed Central

    Jordan, Shawn N.; Davies, Tim; Zhuravlev, Yelena; Dumont, Julien; Shirasu-Hiza, Mimi

    2016-01-01

    Cytokinesis, the physical division of one cell into two, is thought to be fundamentally similar in most animal cell divisions and driven by the constriction of a contractile ring positioned and controlled solely by the mitotic spindle. During asymmetric cell divisions, the core polarity machinery (partitioning defective [PAR] proteins) controls the unequal inheritance of key cell fate determinants. Here, we show that in asymmetrically dividing Caenorhabditis elegans embryos, the cortical PAR proteins (including the small guanosine triphosphatase CDC-42) have an active role in regulating recruitment of a critical component of the contractile ring, filamentous actin (F-actin). We found that the cortical PAR proteins are required for the retention of anillin and septin in the anterior pole, which are cytokinesis proteins that our genetic data suggest act as inhibitors of F-actin at the contractile ring. Collectively, our results suggest that the cortical PAR proteins coordinate the establishment of cell polarity with the physical process of cytokinesis during asymmetric cell division to ensure the fidelity of daughter cell formation. PMID:26728855

  18. Tuberculosis prevalence and risk factors for water buffalo in Pará, Brazil.

    PubMed

    Barbosa, José D; da Silva, Jenevaldo B; Rangel, Charles P; da Fonseca, Adivaldo H; Silva, Natália S; Bomjardim, Henrique A; Freitas, Nayra F Q R

    2014-03-01

    The prevalence of and possible risk factors for tuberculosis were studied in water buffalo from Pará, Brazil. In this study, 3,917 pregnant and nonpregnant female Murrah and Mediterranean buffaloes were studied; 2,089 originated from Marajó Island, and 1,108 were from the mainland. The comparative cervical tuberculin test was used as a diagnostic test for tuberculosis in these animals. The prevalence of positive buffaloes was 3.5 % (100/2,809) on Marajó Island and 7.2 % (80/1,108) on the mainland. The municipalities with the highest tuberculosis prevalence rates in animals were Ipixuna do Pará (10.1 %), Marapanim (9.8 %), Chaves (9.4 %), Paragominas (8.6 %), and Cachoeira do Arari (6.7 %). The tuberculosis prevalence was not significantly different between the Murrah (4.3 %) and Mediterranean (4.8 %) breeds or between pregnant (5 %) and nonpregnant (4.3 %) buffaloes. Tuberculosis was detected in water buffaloes from Pará, Brazil; the mainland buffalo exhibited the highest tuberculosis prevalence. These results indicate that this disease is dangerous to public health and buffalo farming in Pará.

  19. The Utility of Clinicians Ratings of Anxiety Using the Pediatric Anxiety Rating Scale (PARS)

    ERIC Educational Resources Information Center

    Ginsburg, Golda S.; Keeton, Courtney P.; Drazdowski, Tess K.; Riddle, Mark A.

    2011-01-01

    Clinician ratings of anxiety hold the promise of clarifying discrepancies often found between child and parent reports of anxiety. The Pediatric Anxiety Rating Scale (PARS) is a clinician-administered instrument that assesses the frequency, severity, and impairment of common pediatric anxiety disorders and has been used as a primary outcome…

  20. Participation and Participatory Action Research (PAR) in Environmental Education Processes: For What Are People Empowered?

    ERIC Educational Resources Information Center

    Le Grange, Lesley

    2009-01-01

    Participatory action research (PAR) derived from anti-colonial struggles in the third world in the 1960s. Traditionally it has been a method of the margins because of its commitment to linking social justice to research. Because of its counter-hegemonic tendency it has had great appeal among environmental educators advocating a socially critical…

  1. [Capsulotomy through the pars plana in the eye with pseudophakia of the posterior chamber].

    PubMed

    Radian, A B; Mocanu, C

    1996-01-01

    It described one surgical technique for capsulotomy in the case of secondary cataract at an eye with pseudophakic by posterior chamber. The approaching makes with an simple instrument, through pars plana, the tearing of posterior capsule making under control with operator microscope, in area of visual axie, excluding any possibility to harm the lens, its luxation in vitreous or anothers complications.

  2. The interaction between uPAR and vitronectin triggers ligand-independent adhesion signalling by integrins

    PubMed Central

    Ferraris, Gian Maria Sarra; Schulte, Carsten; Buttiglione, Valentina; De Lorenzi, Valentina; Piontini, Andrea; Galluzzi, Massimiliano; Podestà, Alessandro; Madsen, Chris D; Sidenius, Nicolai

    2014-01-01

    The urokinase-type plasminogen activator receptor (uPAR) is a non-integrin vitronectin (VN) cell adhesion receptor linked to the plasma membrane by a glycolipid anchor. Through structure–function analyses of uPAR, VN and integrins, we document that uPAR-mediated cell adhesion to VN triggers a novel type of integrin signalling that is independent of integrin–matrix engagement. The signalling is fully active on VN mutants deficient in integrin binding site and is also efficiently transduced by integrins deficient in ligand binding. Although integrin ligation is dispensable, signalling is crucially dependent upon an active conformation of the integrin and its association with intracellular adaptors such as talin. This non-canonical integrin signalling is not restricted to uPAR as it poses no structural constraints to the receptor mediating cell attachment. In contrast to canonical integrin signalling, where integrins form direct mechanical links between the ECM and the cytoskeleton, the molecular mechanism enabling the crosstalk between non-integrin adhesion receptors and integrins is dependent upon membrane tension. This suggests that for this type of signalling, the membrane represents a critical component of the molecular clutch. PMID:25168639

  3. Crystal Structure of Thrombin Bound to the Uncleaved Extracellular Fragment of PAR1

    SciTech Connect

    Gandhi, Prafull S.; Chen, Zhiwei; Di Cera, Enrico

    2010-05-11

    Abundant structural information exists on how thrombin recognizes ligands at the active site or at exosites separate from the active site region, but remarkably little is known about how thrombin recognizes substrates that bridge both the active site and exosite I. The case of the protease-activated receptor PAR1 is particularly relevant in view of the plethora of biological effects associated with its activation by thrombin. Here, we present the 1.8 {angstrom} resolution structure of thrombin S195A in complex with a 30-residue long uncleaved extracellular fragment of PAR1 that documents for the first time a productive binding mode bridging the active site and exosite I. The structure reveals two unexpected features of the thrombin-PAR1 interaction. The acidic P3 residue of PAR1, Asp{sup 39}, does not hinder binding to the active site and actually makes favorable interactions with Gly{sup 219} of thrombin. The tethered ligand domain shows a considerable degree of disorder even when bound to thrombin. The results fill a significant gap in our understanding of the molecular mechanisms of recognition by thrombin in ways that are relevant to other physiological substrates.

  4. The loss of circadian PAR bZip transcription factors results in epilepsy

    PubMed Central

    Gachon, Frédéric; Fonjallaz, Philippe; Damiola, Francesca; Gos, Pascal; Kodama, Tohru; Zakany, Jozsef; Duboule, Denis; Petit, Brice; Tafti, Mehdi; Schibler, Ueli

    2004-01-01

    DBP (albumin D-site-binding protein), HLF (hepatic leukemia factor), and TEF (thyrotroph embryonic factor) are the three members of the PAR bZip (proline and acidic amino acid-rich basic leucine zipper) transcription factor family. All three of these transcriptional regulatory proteins accumulate with robust circadian rhythms in tissues with high amplitudes of clock gene expression, such as the suprachiasmatic nucleus (SCN) and the liver. However, they are expressed at nearly invariable levels in most brain regions, in which clock gene expression only cycles with low amplitude. Here we show that mice deficient for all three PAR bZip proteins are highly susceptible to generalized spontaneous and audiogenic epilepsies that frequently are lethal. Transcriptome profiling revealed pyridoxal kinase (Pdxk) as a target gene of PAR bZip proteins in both liver and brain. Pyridoxal kinase converts vitamin B6 derivatives into pyridoxal phosphate (PLP), the coenzyme of many enzymes involved in amino acid and neurotransmitter metabolism. PAR bZip-deficient mice show decreased brain levels of PLP, serotonin, and dopamine, and such changes have previously been reported to cause epilepsies in other systems. Hence, the expression of some clock-controlled genes, such as Pdxk, may have to remain within narrow limits in the brain. This could explain why the circadian oscillator has evolved to generate only low-amplitude cycles in most brain regions. PMID:15175240

  5. Kis antitoxin couples plasmid R1 replication and parD (kis,kid) maintenance modules.

    PubMed

    López-Villarejo, Juan; Diago-Navarro, Elizabeth; Hernández-Arriaga, Ana María; Díaz-Orejas, Ramón

    2012-03-01

    The coupling between the replication and parD (kis, kid) maintenance modules of R1 has been revisited here by the isolation of a significant collection of conditional replication mutants in the pKN1562 mini-R1 plasmid, and in its derivative, pJLV01, specifically affected in the RNase activity of the Kid toxin. This new analysis aims to identify key factors in this coupling. For this purpose we have quantified and characterized the restriction introduced by parD to isolate conditional replication mutants of this plasmid, a signature of the modular coupling. This restriction depends on the RNase activity of the Kid toxin and it is relieved by either over-expression of the Kis antitoxin or by preventing its degradation by Lon and ClpAP proteases. Based on these data and on the correlation between copy numbers and parD transcriptional levels obtained in the different mutants, it is proposed that a reduction of Kis antitoxin levels in response to inefficient plasmid replication is the key factor for coupling plasmid replication and parD modules.

  6. Participatory Action Research: Reflections on Critical Incidents in a PAR Project.

    ERIC Educational Resources Information Center

    Santelli, Betsy; Singer, George H. S.; DiVenere, Nancy; Ginsberg, Connie; Powers, Laurie E.

    1998-01-01

    This article describes a participatory action research (PAR) project designed to evaluate Parent to Parent programs in five states. The process of developing a shared understanding of the program and of the purpose for evaluating them, along with an on-going willingness of parents and researchers to compromise, led to creative solutions to…

  7. Plant-derived SAC domain of PAR-4 (Prostate Apoptosis Response 4) exhibits growth inhibitory effects in prostate cancer cells

    PubMed Central

    Sarkar, Shayan; Jain, Sumeet; Rai, Vineeta; Sahoo, Dipak K.; Raha, Sumita; Suklabaidya, Sujit; Senapati, Shantibhusan; Rangnekar, Vivek M.; Maiti, Indu B.; Dey, Nrisingha

    2015-01-01

    The gene Par-4 (Prostate Apoptosis Response 4) was originally identified in prostate cancer cells undergoing apoptosis and its product Par-4 showed cancer specific pro-apoptotic activity. Particularly, the SAC domain of Par-4 (SAC-Par-4) selectively kills cancer cells leaving normal cells unaffected. The therapeutic significance of bioactive SAC-Par-4 is enormous in cancer biology; however, its large scale production is still a matter of concern. Here we report the production of SAC-Par-4-GFP fusion protein coupled to translational enhancer sequence (5′ AMV) and apoplast signal peptide (aTP) in transgenic Nicotiana tabacum cv. Samsun NN plants under the control of a unique recombinant promoter M24. Transgene integration was confirmed by genomic DNA PCR, Southern and Northern blotting, Real-time PCR, and Nuclear run-on assays. Results of Western blot analysis and ELISA confirmed expression of recombinant SAC-Par-4-GFP protein and it was as high as 0.15% of total soluble protein. In addition, we found that targeting of plant recombinant SAC-Par-4-GFP to the apoplast and endoplasmic reticulum (ER) was essential for the stability of plant recombinant protein in comparison to the bacterial derived SAC-Par-4. Deglycosylation analysis demonstrated that ER-targeted SAC-Par-4-GFP-SEKDEL undergoes O-linked glycosylation unlike apoplast-targeted SAC-Par-4-GFP. Furthermore, various in vitro studies like mammalian cells proliferation assay (MTT), apoptosis induction assays, and NF-κB suppression suggested the cytotoxic and apoptotic properties of plant-derived SAC-Par-4-GFP against multiple prostate cancer cell lines. Additionally, pre-treatment of MAT-LyLu prostate cancer cells with purified SAC-Par-4-GFP significantly delayed the onset of tumor in a syngeneic rat prostate cancer model. Taken altogether, we proclaim that plant made SAC-Par-4 may become a useful alternate therapy for effectively alleviating cancer in the new era. PMID:26500666

  8. Project Plan 7930 Cell G PaR Remote Handling System Replacement

    SciTech Connect

    Kinney, Kathryn A

    2009-10-01

    For over 40 years the US Department of Energy (DOE) and its predecessors have made Californium-252 ({sup 252}Cf) available for a wide range of industries including medical, nuclear fuels, mining, military and national security. The Radiochemical Engineering Development Center (REDC) located within the Oak Ridge National Laboratory (ORNL) processes irradiated production targets from the High Flux Isotope Reactor (HFIR). Operations in Building 7930, Cell G provide over 70% of the world's demand for {sup 252}Cf. Building 7930 was constructed and equipped in the mid-1960s. Current operations for {sup 252}Cf processing in Building 7930, Cell G require use of through-the-wall manipulators and the PaR Remote Handling System. Maintenance and repairs for the manipulators is readily accomplished by removal of the manipulator and relocation to a repair shop where hands-on work can be performed in glove boxes. Contamination inside cell G does not currently allow manned entry and no provisions were created for a maintenance area inside the cell. There has been no maintenance of the PaR system or upgrades, leaving operations vulnerable should the system have a catastrophic failure. The Cell G PaR system is currently being operated in a run to failure mode. As the manipulator is now 40+ years old there is significant risk in this method of operation. In 2006 an assessment was completed that resulted in recommendations for replacing the manipulator operator control and power centers which are used to control and power the PaR manipulator in Cell G. In mid-2008 the chain for the bridge drive failed and subsequent examinations indicated several damaged links (see Figure 1). To continue operations the PaR manipulator arm is being used to push and pull the bridge as a workaround. A retrieval tool was fabricated, tested and staged inside Cell G that will allow positioning of the bridge and manipulator arm for removal from the cell should the PaR system completely fail. A fully

  9. La structure de l'eau liquide: Une etude thermique par spectroscopie infrarouge

    NASA Astrophysics Data System (ADS)

    Larouche, Pascal

    Le probleme de la structure de l'eau liquide est important car l'eau est le liquide le plus present sur Terre, et complexe, la quete d'un modele precis pour decrire comment fonctionne ce liquide ayant debute des la fin du dix-neuvieme siecle. Cette etude aborde ce probleme en etudiant l'effet de l'augmentation de la temperature sur H2O et D 2O purs a l'aide de la spectroscopie infrarouge. L'intervalle de temperatures scrute est 29--93.1°C. Les spectres enregistres sont des spectres MIR-ATR entre 650 et 6000 cm-1 . L'analyse par facteurs de ces donnees permet de montrer que deux et seulement deux facteurs principaux sont necessaires pour decomposer tous les spectres experimentaux. Ces resultats sont confirmes grace a l'analyse par facteurs de spectres de la region FIR. Par la suite, la transformation en spectres de la partie reelle n et imaginaire k de l'indice de refraction permet de combiner les donnees des regions MIR et FIR. Une fois ce calcul termine, les spectres de transmission complets de H 2O et D2O entre 25 et 90°C sont connus. Ils sont ensuite utilises pour calculer par extrapolation le spectre des especes constituant l'eau liquide, puis leur abondance en fonction de la temperature. L'extrapolation de ces abondances montre que les especes correspondent a des temperatures limites de --18 et 122°C. Par la suite, la decomposition gaussienne des spectres d'especes met en evidence la riche structure de ces objets et permet de demontrer que l'apparent deplacement du massif d'absorption OH (OD) est produit par une variation de l'intensite des bandes et non pas de leur deplacement. L'examen attentif des spectres des especes prouve qu'il n'y a pas de OH libres crees par l'augmentation de la temperature: meme a 93.1°C, chaque molecule possede quatre liens-H. Ces conclusions sont de plus confirmees par une analyse thermodynamique du passage des molecules de la phase solide a la phase gazeuse. Pour diversifier la nature des resultats experimentaux utilises, des

  10. Water quality, phytoplankton and zooplankton of Par Pond and Pond B. Volume 2. Phytoplankton. Final report, January 1984-June 1985

    SciTech Connect

    Chimney, M.J.; Cody, W.R.; Starkel, W.M.

    1985-08-01

    This document reports on the Par Pond and Pond B phytoplankton community. The objectives of this study were to (1) characterize the biological communities and environmental conditions in Par Pond and Pond B; (2) assess the impact and significance of entrainment losses of plankton at the Par Pond pumphouse; (3) assess the impact of heated discharge on the biotic communities throughout the reservoir; and (4) help determine if Par Pond maintains an indigenous balanced biological community as defined in state and federal regulations. A total of 368 phytoplankton taxa, representing all the major taxonomic groups characteristic of North American freshwaters, were identified from Par Pond and Pond B during this study (73 Bacillariophyta, 166 Chlorophyta, 30 Chrysophyta, 5 Cryptophyta, 47 Cyanophyta, 18 Euglenophyta, 11 phytoflaggelates and 18 Pyrrophyta).

  11. ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data

    DOE PAGES

    Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S.; ...

    2017-02-23

    Here, a newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides,more » important for metal extraction chemistry, are parametrized using ParFit.« less

  12. PAR2 exerts local protection against acute pancreatitis via modulation of MAP kinase and MAP kinase phosphatase signaling.

    PubMed

    Namkung, Wan; Yoon, Jae Seok; Kim, Kyung Hwan; Lee, Min Goo

    2008-11-01

    During acute pancreatitis, protease-activated receptor 2 (PAR2) can be activated by interstitially released trypsin. In the mild form of pancreatitis, PAR2 activation exerts local protection against intrapancreatic damage, whereas, in the severe form of pancreatitis, PAR2 activation mediates some systemic complications. This study aimed to identify the molecular mechanisms of PAR2-mediated protective effects against intrapancreatic damage. A mild form of acute pancreatitis was induced by an intraperitoneal injection of caerulein (40 microg/kg) in rats. Effects of PAR2 activation on intrapancreatic damage and on mitogen-activated protein (MAP) kinase signaling were assessed. Caerulein treatment activated extracellular signal-regulated kinase (ERK) and c-Jun NH(2)-terminal kinase (JNK) within 15 min and maintained phosphorylation of ERK and JNK for 2 h in the rat pancreas. Although PAR2 activation by the pretreatment with PAR2-activating peptide (AP) itself increased ERK phosphorylation in rat pancreas, the same treatment remarkably decreased caerulein-induced activation of ERK and JNK principally by accelerating their dephosphorylation. Inhibition of ERK and JNK phosphorylation by the pretreatment with MAP/ERK kinase (MEK) or JNK inhibitors decreased caerulein-induced pancreatic damage that was similar to the effect induced by PAR2-AP. Notably, in caerulein-treated rats, PAR2-AP cotreatment highly increased the expression of a group of MAP kinase phosphatases (MKPs) that deactivate ERK and JNK. The above results imply that downregulation of MAP kinase signaling by MKP induction is a key mechanism involved in the protective effects of PAR2 activation on caerulein-induced intrapancreatic damage.

  13. Activation of PAR2 receptors sensitizes primary afferents and causes leukocyte rolling and adherence in the rat knee joint

    PubMed Central

    Russell, FA; Schuelert, N; Veldhoen, VE; Hollenberg, MD; McDougall, JJ

    2012-01-01

    Background and Purpose The PAR2 receptors are involved in chronic arthritis by mechanisms that are as yet unclear. Here, we examined PAR2 activation in the rat knee joint. Experimental Approach PAR2 in rat knee joint dorsal root ganglia (DRG) cells at L3-L5, retrogradely labelled with Fluoro-gold (FG) were demonstrated immunohistochemically. Electrophysiological recordings from knee joint nerve fibres in urethane anaesthetized Wistar rats assessed the effects of stimulating joint PAR2 with its activating peptide, 2-furoyl-LIGRLO-NH2 (1–100 nmol·100 μL−1, via close intra-arterial injection). Fibre firing rate was recorded during joint rotations before and 15 min after administration of PAR2 activating peptide or control peptide. Leukocyte kinetics in the synovial vasculature upon PAR2 activation were followed by intravital microscopy for 60 min after perfusion of 2-furoyl-LIGRLO-NH2 or control peptide. Roles for transient receptor potential vanilloid-1 (TRPV1) or neurokinin-1 (NK1) receptors in the PAR2 responses were assessed using the selective antagonists, SB366791 and RP67580 respectively. Key Results PAR2 were expressed in 59 ± 5% of FG-positive DRG cells; 100 nmol 2-furoyl-LIGRLO-NH2 increased joint fibre firing rate during normal and noxious rotation, maximal at 3 min (normal; 110 ± 43%, noxious; 90 ± 31%). 2-Furoyl-LIGRLO-NH2 also significantly increased leukocyte rolling and adhesion over 60 min. All these effects were blocked by pre-treatment with SB366791 and RP67580 (P < 0.05 compared with 2-furoyl-LIGRLO-NH2 alone). Conclusions and Implications PAR2 receptors play an acute inflammatory role in the knee joint via TRPV1- and NK1-dependent mechanisms involving both PAR2-mediated neuronal sensitization and leukocyte trafficking. PMID:22849826

  14. Simulation de l'accretion de glace sur un obstacle bidimensionnel par la methode des bissectrices et par la modelisation des ruisselets et des gouttes de surface

    NASA Astrophysics Data System (ADS)

    Fortin, Guy

    Le LIMA (Laboratoire International des Materiaux Antigivre) en collaboration avec le CIRA (Italian Aerospace Research Centre) a developpe un logiciel simulant l'accretion de la glace en regimes sec et humide sur un objet bidimensionnel fixe. L'approche utilisee s'appuie sur les travaux de Lozowski pour les bilans energetiques, sur une etude du comportement du film d'eau, des ruisselets et des gouttes de surface pour le calcul des rugosites et des masses d'eau residuelle, ainsi que sur une methode de bissectrice pour l'evolution de la surface de glace. La contribution du CIRA a ete de fournir le logiciel pour le calcul des ecoulements et de la captation. Le bilan energetique base sur la conservation de l'energie est la sommation de la chaleur latente de fusion, d'evaporation et de sublimation, du rechauffement adiabatique et cinetique, et des pertes de chaleur par convection et conduction, ainsi que de l'evolution thermodynamique de l'eau de son etat initial a son etat final. La densite de la glace, qui a un impact important sur la simulation, est calculee a partir d'une correlation empirique developpee avec les cylindres tournants. En se basant sur les travaux de Al-Khalil et Hansman, le comportement des gouttes en regimes sec et humide a ete decrit analytiquement, ce qui a mene a determiner la hauteur maximale que peuvent atteindre les gouttes avant mouvement. Cette hauteur, appelee hauteur de mouvement, permet de determiner l'etat de l'eau sur la surface (film, ruisselets ou gouttes), ainsi que la hauteur des rugosites lorsque l'eau existe sous forme de gouttes ou de ruisselets. La hauteur de mouvement est determinee par l'equilibre entre les forces de cisaillement, induites par les effets aerodynamiques et gravitationnels evalues pour une goutte non deformee, et la force de cisaillement, induite par la tension de surface et la deformation de la goutte. Elle a ete validee en laboratoire et la precision obtenue pour la partie aerodynamique et gravitationnelle est

  15. Etude par spectroscopie de Coulomb de points quantiques lateraux individuels et couples

    NASA Astrophysics Data System (ADS)

    Pioro-Ladriere, Michel

    Des points quantiques contenant un nombre discret et variable d'electrons sont formes dans un gaz bi-dimensionnel d'electrons a l'aide de grilles metalliques. Le transport electrique, le blocage de spin et la detection de charge sont employes comme outils spectroscopiques permettant de sonder les proprietes de ces nanostructures. Ces techniques permettent aussi de controler exactement le nombres d'electrons confines dans des points quantiques individuels et couples en utilisant un patron de grille judicieux. Une technique de refroidissement en tension est developpee afin de minimiser les effets parasites du bruit telegraphique. Ce type de bruit de charge deteriore la stabilite des nanostructures laterales par l'activation d'un minuscule courant de fuite entre les grilles et le gaz bi-dimensionnel. Un modele expliquant le role du refroidissement en tension sur le courant de fuite est presente. L'activation du courant de fuite est confirmee par detection de charge. Les effets des interactions entre les electrons pieges dans un point quantique sont ensuite etudies dans un regime ou il est possible de comparer les resulats experimentaux avec ceux obtenus par diagonalisation exacte. L'etude demontre que la phase associee au facteur de remplissage nu = 2 est instable au-dessus d'un nombre critique d'electrons. Cette instabilite est confirmee experimentalement par blocage de spin. On demontre aussi l'existence d'etats correles dans le regime des renversements de spin, associe au passage de la phase nu = 2 a nu = 1. Les etats correles sont identifies par spectroscopie en transport non lineaire. Cette caracterisation du diagramme de phase de points individuels permet de coupler deux points quantiques configures a nu = 2. Pour ce regime, la nanostructure se comporte comme un systeme a deux niveaux pouvant contenir entre un et quatre electrons de valence et ce, meme si le nombre total d'electrons est plus eleve. Les degres de liberte de charge et de spin des deux points

  16. Impacts of Light Use Efficiency and fPAR Parameterization on Gross Primary Production Modeling

    NASA Technical Reports Server (NTRS)

    Cheng, Yen-Ben; Zhang, Qingyuan; Lyapustin, Alexei I.; Wang, Yujie; Middleton, Elizabeth M.

    2014-01-01

    This study examines the impact of parameterization of two variables, light use efficiency (LUE) and the fraction of absorbed photosynthetically active radiation (fPAR or fAPAR), on gross primary production(GPP) modeling. Carbon sequestration by terrestrial plants is a key factor to a comprehensive under-standing of the carbon budget at global scale. In this context, accurate measurements and estimates of GPP will allow us to achieve improved carbon monitoring and to quantitatively assess impacts from cli-mate changes and human activities. Spaceborne remote sensing observations can provide a variety of land surface parameterizations for modeling photosynthetic activities at various spatial and temporal scales. This study utilizes a simple GPP model based on LUE concept and different land surface parameterizations to evaluate the model and monitor GPP. Two maize-soybean rotation fields in Nebraska, USA and the Bartlett Experimental Forest in New Hampshire, USA were selected for study. Tower-based eddy-covariance carbon exchange and PAR measurements were collected from the FLUXNET Synthesis Dataset. For the model parameterization, we utilized different values of LUE and the fPAR derived from various algorithms. We adapted the approach and parameters from the MODIS MOD17 Biome Properties Look-Up Table (BPLUT) to derive LUE. We also used a site-specific analytic approach with tower-based Net Ecosystem Exchange (NEE) and PAR to estimate maximum potential LUE (LUEmax) to derive LUE. For the fPAR parameter, the MODIS MOD15A2 fPAR product was used. We also utilized fAPAR chl, a parameter accounting for the fAPAR linked to the chlorophyll-containing canopy fraction. fAPAR chl was obtained by inversion of a radiative transfer model, which used the MODIS-based reflectances in bands 1-7 produced by Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm. fAPAR chl exhibited seasonal dynamics more similar with the flux tower based GPP than MOD15A2 fPAR, especially

  17. Developpement d'algorithmes de reconstruction statistique appliques en tomographie rayons-X assistee par ordinateur

    NASA Astrophysics Data System (ADS)

    Thibaudeau, Christian

    La tomodensitometrie (TDM) permet d'obtenir, et ce de facon non invasive, une image tridimensionnelle de l'anatomie interne d'un sujet. Elle constitue l'evolution logique de la radiographie et permet l'observation d'un volume sous differents plans (sagittal, coronal, axial ou n'importe quel autre plan). La TDM peut avantageusement completer la tomographie d'emission par positrons (TEP), un outil de predilection utilise en recherche biomedicale et pour le diagnostic du cancer. La TEP fournit une information fonctionnelle, physiologique et metabolique, permettant la localisation et la quantification de radiotraceurs a l'interieur du corps humain. Cette derniere possede une sensibilite inegalee, mais peut neanmoins souffrir d'une faible resolution spatiale et d'un manque de repere anatomique selon le radiotraceur utilise. La combinaison, ou fusion, des images TEP et TDM permet d'obtenir cette localisation anatomique de la distribution du radiotraceur. L'image TDM represente une carte de l'attenuation subie par les rayons-X lors de leur passage a travers les tissus. Elle permet donc aussi d'ameliorer la quantification de l'image TEP en offrant la possibilite de corriger pour l'attenuation. L'image TDM s'obtient par la transformation de profils d'attenuation en une image cartesienne pouvant etre interpretee par l'humain. Si la qualite de cette image est fortement influencee par les performances de l'appareil, elle depend aussi grandement de la capacite de l'algorithme de reconstruction a obtenir une representation fidele du milieu image. Les techniques de reconstruction standards, basees sur la retroprojection filtree (FBP, filtered back-projection), reposent sur un modele mathematiquement parfait de la geometrie d'acquisition. Une alternative a cette methode etalon est appelee reconstruction statistique, ou iterative. Elle permet d'obtenir de meilleurs resultats en presence de bruit ou d'une quantite limitee d'information et peut virtuellement s'adapter a toutes formes

  18. 1,25-Dihydroxyvitamin D(3) Inhibits Podocyte uPAR Expression and Reduces Proteinuria

    PubMed Central

    Liu, Shuangxin; Xie, Shaoting; Yang, Yun; Ma, Juan; Deng, Yujun; Wang, Wenjian; Xu, Lixia; Li, Ruizhao; Zhang, Li; Yu, Chunping; Shi, Wei

    2013-01-01

    Background Accumulating studies have demonstrated that 1,25-Dihydroxyvitamin D(3) (1,25(OH)2D3) reduces proteinuria and protects podocytes from injury. Recently, urokinase receptor (uPAR) and its soluble form have been shown to cause podocyte injury and focal segmental glomerulosclerosis (FSGS). Here, our findings showed that 1,25(OH)2D3 did inhibit podocyte uPAR expression and attenuate proteinuria and podocyte injury. Methodology/Principal Findings In this study, the antiproteinuric effect of 1,25(OH)2D3 was examined in the lipopolysaccharide mice model of transient proteinuria (LPS mice) and in the 5/6 nephrectomy rat FSGS model(NTX rats). uPAR protein expression were tested by flow cytometry, immune cytochemistry and western blot analysis, and uPAR mRNA expression by real-time quantitative PCR in cultured podocytes and kidney glomeruli isolated from mice and rats. Podocyte motility was observed by transwell migration assay and wound healing assay. Podocyte foot processes effacement was identified by transmission electron microscopy. We found that 1,25(OH)2D3 inhibited podocyte uPAR mRNA and protein synthesis in LPS-treated podocytes, LPS mice and NTX rats, along with 1,25(OH)2D3 reducing proteinuria in NTX rats and LPS mice.1,25(OH)2D3 reduced glomerulosclerosis in NTX rats and alleviated podocyte foot processes effacement in LPS mice. Transwell migration assay and wound healing assay showed that LPS-induced podocyte motility, irrespective of random or directed motility, were substantially reduced by 1,25(OH)2D3. Conclusions/Significance Our results demonstrated that 1,25(OH)2D3 inhibited podocyte uPAR expression in vitro and in vivo, which may be an unanticipated off target effect of 1,25(OH)2D3 and explain its antiproteinuric effect in the 5/6 nephrectomy rat FSGS model and the LPS mouse model of transient proteinuria. PMID:23741418

  19. Monomer–dimer dynamics and distribution of GPI-anchored uPAR are determined by cell surface protein assemblies

    PubMed Central

    Caiolfa, Valeria R.; Zamai, Moreno; Malengo, Gabriele; Andolfo, Annapaola; Madsen, Chris D.; Sutin, Jason; Digman, Michelle A.; Gratton, Enrico; Blasi, Francesco; Sidenius, Nicolai

    2007-01-01

    To search for functional links between glycosylphosphatidylinositol (GPI) protein monomer–oligomer exchange and membrane dynamics and confinement, we studied urokinase plasminogen activator (uPA) receptor (uPAR), a GPI receptor involved in the regulation of cell adhesion, migration, and proliferation. Using a functionally active fluorescent protein–uPAR in live cells, we analyzed the effect that extracellular matrix proteins and uPAR ligands have on uPAR dynamics and dimerization at the cell membrane. Vitronectin directs the recruitment of dimers and slows down the diffusion of the receptors at the basal membrane. The commitment to uPA–plasminogen activator inhibitor type 1–mediated endocytosis and recycling modifies uPAR diffusion and induces an exchange between uPAR monomers and dimers. This exchange is fully reversible. The data demonstrate that cell surface protein assemblies are important in regulating the dynamics and localization of uPAR at the cell membrane and the exchange of monomers and dimers. These results also provide a strong rationale for dynamic studies of GPI-anchored molecules in live cells at steady state and in the absence of cross-linker/clustering agents. PMID:18056417

  20. Characterization of a point mutation in the parC gene of Mycoplasma bovirhinis associated with fluoroquinolone resistance.

    PubMed

    Hirose, K; Kawasaki, Y; Kotani, K; Abiko, K; Sato, H

    2004-05-01

    Quinolone-resistant (QR) mutants of Mycoplasma bovirhinis strain PG43 (type strain) were generated by stepwise selection in increasing concentrations of enrofloxacin (ENR). An alteration was found in the quinolone resistance-determining region (QRDR) of the parC gene coding for the ParC subunit of topoisomerase IV from these mutants, but not in the gyrA, gyrB, and parE gene coding for the GyrA and GyrB subunits of DNA gyrase and the ParE subunit of topoisomerase IV. Similarly, such an alteration in QRDR of parC was found in the field isolates of M. bovirhinis, which possessed various levels of QR. The substitution of leucine (Leu) by serine (Ser) at position 80 of QRDR of ParC was observed in both QR-mutants and QR-isolates. This is the first report of QR based on a point mutation of the parC gene in M. bovirhinis.

  1. The Clinical Value of Soluble Urokinase Plasminogen Activator Receptor (suPAR) Levels in Autoimmune Connective Tissue Disorders

    PubMed Central

    Toldi, Gergely; Balog, Attila

    2016-01-01

    The assessment of the general inflammatory condition of patients with autoimmune connective tissue disorders (ACTD) is a major challenge. The use of traditional inflammatory markers including CRP-levels and erythrocyte sedimentation rate (ESR) is limited by several preanalytical factors and their low specificities. Soluble urokinase plasminogen activator receptor (suPAR) is one of the novel candidate markers that is increasingly used in immune mediated disorders. In our studies we compared suPAR levels of patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and ankylosing spondylitis with those of healthy controls. suPAR provided valuable clinical information on disease activity in RA, SLE and SSc. We identified a subgroup of remitted RA patients, who presented still clinical symptoms of inflammatory activity which correlated to high plasma suPAR (while ESR and CRP were normal). In SLE we established specific suPAR cut-off values that support the discrimination between patients with high and those with moderate SLE activity. In patients with SSc suPAR correlated with objective measures of lung and other complications. In the majority of ACTDs including SLE, SSc or RA, suPAR is seemingly a good biomarker that would provide valuable clinical information. However, before the introduction of this novel parameter in laboratory repertoire important issues should be elucidated. These include the establishment of appropriate and disease specific cutoff values, clarification of interfering preanalytical values and underlying conditions and declaration of age- and gender-specific reference ranges. PMID:27683525

  2. The Par3/aPKC interaction is essential for end bud remodeling and progenitor differentiation during mammary gland morphogenesis

    PubMed Central

    McCaffrey, Luke Martin; Macara, Ian G.

    2009-01-01

    Mammalian polarity proteins have been studied predominantly in cell culture systems, and little is known about their functions in vivo. To address this issue, we used a shRNA lentiviral system to manipulate gene expression in mouse mammary stem/progenitor cells. Transplantation of Par3-depleted stem/progenitor cells into the mammary fat pad severely disrupted mammary development, and glands were characterized by ductal hyperplasia, luminal filling, and highly disorganized end bud structures that were unable to remodel into normal ductal structures. Unexpectedly, Par3-depleted mammary glands also had an expanded progenitor population. We identified a novel function for the atypical protein kinase C (aPKC)-binding domain of Par3 in restricting Par3 and aPKC to the apical region in mammary epithelia in vivo, and found that mammary morphogenesis is dependent on the ability of Par3 to directly bind aPKC. These results reveal a new function for Par3 in the regulation of progenitor differentiation and epithelial morphogenesis in vivo and demonstrate for the first time an essential requirement for the Par3–aPKC interaction. PMID:19528321

  3. Graded hedgehog and fibroblast growth factor signaling independently regulate pituitary cell fates and help establish the pars distalis and pars intermedia of the zebrafish adenohypophysis.

    PubMed

    Guner, Burcu; Ozacar, A Tuba; Thomas, Jeanne E; Karlstrom, Rolf O

    2008-09-01

    The vertebrate adenohypophysis forms as a placode at the anterior margin of the neural plate, requiring both hedgehog (Hh) and fibroblast growth factor (Fgf) mediated cell-cell signaling for induction and survival of endocrine cell types. Using small molecule inhibitors to modulate signaling levels during zebrafish development we show that graded Hh and Fgf signaling independently help establish the two subdomains of the adenohypophysis, the anteriorly located pars distalis (PD) and the posterior pars intermedia (PI). High levels of Hh signaling are required for formation of the PD and differentiation of anterior endocrine cell types, whereas lower levels of Hh signaling are required for formation of the PI and differentiation of posterior endocrine cell types. In contrast, high Fgf signaling levels are required for formation of the PI and posterior endocrine cell differentiation, whereas anterior regions require lower levels of Fgf signaling. Based on live observations and marker analyses, we show that the PD forms first at the midline closest to the central nervous system source of Sonic hedgehog. In contrast the PI appears to form from more lateral/posterior cells close to a central nervous system source of Fgf3. Together our data show that graded Hh and Fgf signaling independently direct induction of the PD and PI and help establish endocrine cell fates along the anterior/posterior axis of the zebrafish adenohypophysis. These data suggest that there are distinct origins and signaling requirements for the PD and PI.

  4. PET imaging of urokinase-type plasminogen activator receptor (uPAR) in prostate cancer: current status and future perspectives.

    PubMed

    Skovgaard, Dorthe; Persson, Morten; Kjaer, Andreas

    2016-01-01

    Overexpression of urokinase-type plasminogen activator receptors (uPAR) represents an important biomarker for aggressiveness in most common malignant diseases, including prostate cancer (PC). Accordingly, uPAR expression either assessed directly in malignant PC tissue or assessed directly in plasma (intact/cleaved forms)-provides independent additional clinical information to that contributed by PSA, Gleason score, and other relevant pathological and clinical parameters. In this respect, non-invasive molecular imaging by positron emission tomography (PET) offers a very attractive technology platform, which can provide the required quantitative information on the uPAR expression profile, without the need for invasive procedures and the risk of missing the target due to tumor heterogeneity. These observations support non-invasive PET imaging of uPAR in PC as a clinically relevant diagnostic and prognostic imaging method. In this review, we will focus on the recent development of uPAR PET and the relevance within prostate cancer imaging. Novel antibody and small-molecule radiotracers-targeting uPAR, including a series of uPAR-targeting PET ligands, based on the high affinity peptide ligand AE105, have been synthesized and tested in vitro and in vivo in preclinical murine xenograft models and, recently, in a first-ever clinical uPAR PET study in cancer patients, including patients with PC. In this phase I study, a high and specific uptake of the tracer (64)Cu-DOTA-AE105 was found in both primary tumors and lymph node metastases. The results are encouraging and support large-scale clinical trials to determine the utility of uPAR PET in the management of patients with PC with the goal of improving outcome.

  5. Ground validation of Dual Precipitation Radar (DPR) on GPM by rapid scan Phased Array weahter Radar (PAR)

    NASA Astrophysics Data System (ADS)

    Hirano, Y.; Mega, T.; Shimamura, S.; Wu, T.; Kikuchi, H.; Ushio, T.; Yoshikawa, E.; Chandra, C. V.

    2014-12-01

    The core observatory satellite of the Global Precipitation Measurement (GPM) mission was launched on February 27th 2014. The Dual-frequency Precipitation Radar (DPR) on the GPM core observatory is the succession of the TRMM Precipitation Radar (PR). The DPR consists of a Ku-band precipitation radar and a Ka-band precipitation radar. The DPR is expected to be more sensitive than the PR especially in the measurement of light rainfall and snowfall in high latitude regions. Because of the difference of spatial and temporal resolutions, Space Radar (SR) and conventional type of Ground Radar (GR) are hard to compare.The SR observes each point of earth in short time, for example one footprint is an observation in some microseconds. Rain-gauge measurements have accurate rainfall rate, but rain-gage observes small area and accumulated rainfall in some minutes. The conventional GR can cover a wide area, however, a volume scan requires several minutes. The Phased Array weather Radar (PAR) is developed by Osaka University, Toshiba, and NICT. The PAR is a weather-radar on X-band within 100m range sampling. High spatial and temporal resolution is achieved by the PAR with pulse compression and the digital beam-forming technique. The PAR transmits a wide beam and receives narrow beams by using digital beam forming. Then, the PAR observes many elevation angles from a single pulse. The time of each volume scan is 10-30 seconds in operation, typically 30 seconds. The study shows comparisons between the DPR and the PAR by more similar spatial and temporal resolution. The rainfall region of DPR is similar to the one of PAR. Correlation coefficient of both radar reflectivity suggests more than 0.8 in the 20km range of PAR. As a result, it is considered that DPR can observe with high accuracy. We present the case study which DPR overpassed the PAR observation region in detail.

  6. Physical activity on prescription schemes (PARS): do programme characteristics influence effectiveness? Results of a systematic review and meta-analyses

    PubMed Central

    Arsenijevic, Jelena; Groot, Wim

    2017-01-01

    Background Physical activity on prescription schemes (PARS) are health promotion programmes that have been implemented in various countries. The aim of this study was to outline the differences in the design of PARS in different countries. This study also explored the differences in the adherence rate to PARS and the self-reported level of physical activity between PARS users in different countries. Method A systematic literature review and meta-analyses were conducted. We searched PubMed and EBASCO in July 2015 and updated our search in September 2015. Studies that reported adherence to the programme and self-reported level of physical activity, published in the English language in a peer-reviewed journal since 2000, were included. The difference in the pooled adherence rate after finishing the PARS programme and the adherence rate before or during the PARS programme was 17% (95% CI 9% to 24%). The difference in the pooled physical activity was 0.93 unit score (95 CI −3.57 to 1.71). For the adherence rate, a meta-regression was conducted. Results In total, 37 studies conducted in 11 different countries met the inclusion criteria. Among them, 31 reported the adherence rate, while the level of physical activity was reported in 17 studies. Results from meta-analyses show that PARS had an effect on the adherence rate of physical activity, while the results from the meta-regressions show that programme characteristics such as type of chronic disease and the follow-up period influenced the adherence rate. Conclusions The effects of PARS on adherence and self-reported physical activity were influenced by programme characteristics and also by the design of the study. Future studies on the effectiveness of PARS should use a prospective longitudinal design and combine quantitative and qualitative data. Furthermore, future evaluation studies should distinguish between evaluating the adherence rate and the self-reported physical activity among participants with different

  7. Agrobacterium tumefaciens pTAR parA promoter region involved in autoregulation, incompatibility and plasmid partitioning.

    PubMed

    Gallie, D R; Kado, C I

    1987-02-05

    The locus responsible for directing proper plasmid partitioning of Agrobacterium tumefaciens pTAR is contained within a 1259 base-pair region. Insertions or deletions within this locus can result in the loss of the plasmid's ability to partition properly. One protein product (parA), approximately 25,000 Mr, is expressed from the par locus in Escherichia coli and A. tumefaciens protein analysis systems in vitro. DNA sequence analysis of the locus revealed a single 23,500 Mr open reading frame, confirming the protein data. A 248 base-pair region immediately upstream from the 23,500 Mr open reading frame, containing an array of 12 seven-base-pair palindromic repeats each of which are separated by exactly ten base-pairs of A + T-rich (75%) sequence, not only serves to provide the promoter but is also involved in parA autoregulation. In addition, this region containing a set of 12 seven-base-pair palindromic repeats, is responsible for plasmid-associated incompatibility within Inc Ag-1 and also functions as the cis-acting recognition site at which parA interacts to bring about partitioning. Transcriptional analysis indicated that only the DNA strand responsible for parA is actively transcribed, and that active transcription of the opposite strand of par can inhibit the production of parA, resulting in plasmid destabilization. The presence of the par locus in a plasmid results in stable inheritance within a wide range of members of Rhizobiaceae. Segregation rates of par-defective derivatives can be influenced by the host.

  8. Comparative analysis of a plant pseudoautosomal region (PAR) in Silene latifolia with the corresponding S. vulgaris autosome

    PubMed Central

    2012-01-01

    Background The sex chromosomes of Silene latifolia are heteromorphic as in mammals, with females being homogametic (XX) and males heterogametic (XY). While recombination occurs along the entire X chromosome in females, recombination between the X and Y chromosomes in males is restricted to the pseudoautosomal region (PAR). In the few mammals so far studied, PARs are often characterized by elevated recombination and mutation rates and high GC content compared with the rest of the genome. However, PARs have not been studied in plants until now. In this paper we report the construction of a BAC library for S. latifolia and the first analysis of a > 100 kb fragment of a S. latifolia PAR that we compare to the homologous autosomal region in the closely related gynodioecious species S. vulgaris. Results Six new sex-linked genes were identified in the S. latifolia PAR, together with numerous transposable elements. The same genes were found on the S. vulgaris autosomal segment, with no enlargement of the predicted coding sequences in S. latifolia. Intergenic regions were on average 1.6 times longer in S. latifolia than in S. vulgaris, mainly as a consequence of the insertion of transposable elements. The GC content did not differ significantly between the PAR region in S. latifolia and the corresponding autosomal region in S. vulgaris. Conclusions Our results demonstrate the usefulness of the BAC library developed here for the analysis of plant sex chromosomes and indicate that the PAR in the evolutionarily young S. latifolia sex chromosomes has diverged from the corresponding autosomal region in the gynodioecious S. vulgaris mainly with respect to the insertion of transposable elements. Gene order between the PAR and autosomal region investigated is conserved, and the PAR does not have the high GC content observed in evolutionarily much older mammalian sex chromosomes. PMID:22681719

  9. Estimation of Downstream Cesium Concentrations Following a Postulated PAR Pond Dam Break

    SciTech Connect

    Chen, K.F.

    2002-07-08

    Following a postulated PAR Pond dam break, some of the PAR Pond sediment including the cesium could be eroded and be transported downstream to the Savannah River through the Lower Three Runs Creek. Studies showed that most of the eroded sediment including the cesium would deposit in the Lower Three Runs Creek and the remainder would discharge to the Savannah River from the mouth of Lower Three Runs Creek. A WASP5 model was developed to simulate the eroded sediment and cesium transport from the Lower Three Runs Creek mouth to the Atlantic coast. The dissolved cesium concentrations at the Highway 301 bridge and near the City of Savannah Industrial and Domestic Water Supply Plant are 30 and 27 pCi/l, respectively. The concentrations at both locations are less than the U. S. Environmental Protection Agency drinking water standard of 200 pCi/l.

  10. Corneal modeling using conic section fits of PAR corneal topography system measurements

    NASA Astrophysics Data System (ADS)

    Zipper, Stanley; Manns, Fabrice; Fernandez, Viviana; Sandadi, Samith; Ho, Arthur; Parel, Jean-Marie A.

    2001-06-01

    The purpose of this study was to measure the average shape and variability of human corneas and to develop a tool for analyzing, height, curvature, and aberrations based on a conic section model. Fresh Eye Bank Eyes were placed in Dextran until the corneal thickness reached a physiological value. The eyes were placed in a custom made holder and measured using an intraoperative PAR Corneal Topography System (CTS) mounted on an operation microscope. Topography was measured before and after removal of the epithelium. A series of MATLAB functions were written to analyze the raw-z (height) data in polar coordinates. The functions fit conic sections to the PAR CTS data along hemi-meridians at 5 degree(s) intervals. The conic shape factor and apical radius were used to calculate and display the curvature. The dependence of these parameters with meridional position was examined.

  11. Manipulation quantique de la lumière par un amplificateur non linéaire

    NASA Astrophysics Data System (ADS)

    Symul, T.; Bencheikh, K.; Levenson, J. A.

    2002-06-01

    Nous proposons un dispositif original, appelé Amplificateur Non Linéaire (ANL), permettant la génération et la manipulation d'états quantiques de la lumière. Ce dispositif permet une compression du bruit quantique de la lumière en dessous de la limite quantique standard plus efficace que celle obtenue par interactions non linéaires du second ordre ou du troisième ordre. Il permet également d'inverser les fluctuations quantiques en intensité de la lumière, et de produire des photons jumeaux ayant des corrélations quantiques plus élevées et plus robustes que ceux produits par un amplificateur paramétrique seul.

  12. Laser Nd:YVO{4} impulsionnel à 914 nm pompé par diode

    NASA Astrophysics Data System (ADS)

    Blandin, P.; Druon, F.; Balembois, F.; Georges, P.; Lévêque-Fort, S.; Fontaine-Aupart, M. P.

    2006-10-01

    Nous présentons ici le premier laser impulsionnel à verrouillage de modes en phase passif directement pompé par diode, utilisant la transition 4F{3 / 2}-4I{9/2} de l'ion néodyme à 914 nm. Le système de pompage utilisé permet d'obtenir un dispositif simple. Le train d'impulsions est obtenu grâce à un miroir à absorbant saturable, l'émission laser à 914 nm étant privilégiée par l'introduction dans la cavité de fortes pertes à 1064 nm. Nous obtenons avec notre dispositif des impulsions à 913.8 nm, de durée 8.8 ps à une cadence de 94 MHz et à une puissance de 86 mW.

  13. Youth empowerment in context: exploring tensions in school-based yPAR.

    PubMed

    Kohfeldt, Danielle; Chhun, Lina; Grace, Sarah; Langhout, Regina Day

    2011-03-01

    In much of the youth empowerment literature, researchers focus on the relationship between youth and adults involved in empowerment programs while neglecting the broader social framework in which these relationships and the program itself functions. Utilizing an ecological model, the current research examines the tensions that surfaced in attempts to create an empowering setting in an after-school PAR program with fifth-graders. Challenging assumptions about youth, structural challenges, and conflicting theories of change are highlighted. Results examine the role of sociocultural context as PAR researchers attempt to create a setting in which students gain skills to become change agents within their school. The study suggests that youth empowerment is a context dependent process that requires attention to a multiplicity of factors that influence possibilities for empowerment via second order change.

  14. BOREAS TE-9 PAR and Leaf Nitrogen Data for NSA Species

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Dang, Qinglai; Margolis, Hank; Coyea, Marie

    2000-01-01

    The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-9 (Terrestrial Ecology) team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. This data set describes the relationship between photosynthetically active radiation (PAR) levels and foliage nitrogen in samples from six sites in the BOREAS Northern Study Area (NSA) collected during the three 1994 intensive field campaigns (IFCs). This information is useful for modeling the vertical distribution of carbon fixation for these different forest types in the boreal forest. The data were collected to quantify the relationship between PAR and leaf nitrogen of black spruce, jack pine, and aspen. The data are available in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  15. Perianesthetic development of diaphragmatic hernia in a horse with equine pituitary pars intermedia dysfunction (PPID)

    PubMed Central

    Shepard, Molly K.; Lee, Wesley L.; Eggleston, Randy B.

    2015-01-01

    A 21-year-old Thoroughbred gelding with a history of equine pituitary pars intermedia dysfunction (PPID) presented with priapism of 2 days’ duration. The horse received a caudal morphine epidural and then underwent corpus cavernosum lavage and phallectomy under general anesthesia. The patient’s recovery featured multiple unsuccessful attempts to stand and his respiratory distress persisted for several hours until he acutely developed severe colic and was euthanized. Necropsy findings revealed a pituitary adenoma of the pars intermedia, bilateral adrenal cortical hyperplasia, and diaphragmatic herniation. This report suggests that horses with PPID may present a greater risk for diaphragmatic hernia under general anesthesia or during procedures placing stress on the diaphragm, including anesthetic recovery. PMID:25565714

  16. Disrupting the right pars opercularis with electrical stimulation frees the song: case report.

    PubMed

    Herbet, Guillaume; Lafargue, Gilles; Almairac, Fabien; Moritz-Gasser, Sylvie; Bonnetblanc, François; Duffau, Hugues

    2015-12-01

    The authors report the first case of a strikingly unusual speech impairment evoked by intraoperative electrostimulation in a 36-year-old right-handed patient, a well-trained singer, who underwent awake surgery for a right fronto-temporo-insular low-grade glioma. Functionally disrupting the pars opercularis of the right inferior frontal gyrus led the patient to automatically switch from a speaking to a singing mode of language production. Given the central role of the right pars opercularis in the inhibitory control network, the authors propose that this finding may be interpreted as possible evidence for a competitive and independent neurocognitive subnetwork devoted to the melodically intoned articulation of words (normal language-based vs singing-based) in subjects with high expertise. From a more clinical perspective, such data may have implications for awake neurosurgery, especially to preserve the quality of life for singers.

  17. Hydraulic and hydrologic evaluation of PAR Pond Dam. Technical evaluation report

    SciTech Connect

    Reich, M.; Wang, P.C.; Khanbilvardi, R.; Bezler, P.

    1993-10-01

    The PAR Pond Dam at Savannah River Plant was constructed in 1958--1959. Seepage, depressions, boils and spring flow were observed in varying locations on the dam in the last few years. Comprehensive geotechnical and hydraulic investigations pertaining to the effects of the above observations on the abilities of the dam to withstand future floods were made in 1991 and early 1993 where dam capacity to survive flooding and seismic events were evaluated. Brookhaven National Laboratory (BNL) was asked by the Department of Energy (EH) to carry out an independent review of the PAR Pond Dam response to future flooding and seismic events. This report addresses the studies made to evaluate the capacity of the dam to survive floods. A companion report will summarize the evaluations performed to assess the seismic capacity of the dam.

  18. Case series of equine pituitary pars intermedia dysfunction in a tropical climate.

    PubMed

    Spelta, C W; Axon, J E

    2012-11-01

    The clinical manifestations of equine pituitary pars intermedia dysfunction (PPID) in temperate climates are well described. The classic presentation is that of an older animal with hirsutism, laminitis, poor muscle tone, pendulous abdomen and weight loss. This case series highlights the additional clinical signs of anhidrosis and heat stress with secondary exercise intolerance that were seen as primary presenting problems in equids with PPID in the hot, humid conditions of a tropical climate. The clinical signs resolved with medical treatment for PPID.

  19. Magnétométrie à hélium par pompage laser: le bilan

    NASA Astrophysics Data System (ADS)

    Gilles, H.; Hamel, J.; Monfort, Y.

    2002-06-01

    Depuis 1986, l'équipe Physique Atomique et Capteurs du CIRIL-ISMRA de Caen étudie les magnétomètres à hélium par pompage laser. On présente ici le bilan de ces travaux de recherche et les performances des deux prototypes (hélium4 et hélium3) réalisés au Laboratoire.

  20. Endophthalmitis following pars plana vitrectomy: a literature review of incidence, causative organisms, and treatment outcomes

    PubMed Central

    Dave, Vivek Pravin; Pathengay, Avinash; Schwartz, Stephen G; Flynn, Harry W

    2014-01-01

    Endophthalmitis following pars plana vitrectomy is a very uncommon cause of endophthalmitis. Cases reported over the last decade show a decrease in incidence over time. To optimize visual outcome, early diagnosis and treatment are essential. In this review we report a summary of the incidence of endophthalmitis following vitrectomy, various risk factors for their occurrence, the microbiological profile and the visual outcomes post treatment. PMID:25382968

  1. K-Area and Par Pond Sewage Sludge Application Sites groundwater monitoring report, Third quarter 1992

    SciTech Connect

    Thompson, C.Y.

    1993-01-01

    During third quarter 1992, the three wells at the K-Area Sewage Sludge Application Site (KSS wells) and the three wells at the Par Pond Sewage Sludge Application Site (PSS wells) were sampled for analyses required each quarter or annually by South Carolina Department of Health and Environmental Control Construction Permit 13,173 and for base-neutral/acid semivolatile constituents. None of the analytical results exceeded standards.

  2. L'analyse par activation de neutrons de réacteur

    NASA Astrophysics Data System (ADS)

    Meyer, G.

    2003-02-01

    Quand les neutrons traversent la matière, certains sont transmis sans interaction, les autres interagissent avec le milieu traversé par diffusion et par absorption. Ce phénomène d'absorption est utilisé pour se protéger des neutrons, mais aussi pour les détecter; il peut également être utilisé pour identifier les noyaux “absorbants" et ainsi analyser le milieu traversé. En effet par différentes réactions nucléaires (n,γ), (n,p), (n,α), (n,fission), on obtient des noyaux résiduels qui sont souvent radioactifs; on dit que l'échantillon est “activé". Si l'on connaît le rendement d'activation et donc le pourcentage de noyaux ainsi “transmutés", les mesures de radioactivité induite vont permettre de déterminer la composition de l'échantillon irradié. Cette méthode dite d'analyse par activation neutronique est pratiquée depuis la découverte du neutron. Elle a permis grâce à sa sélectivité et à sa sensibilité d'avoir accès au domaine des traces et des ultra-traces dans des champs d'application très divers comme la métallurgie, l'archéologie, la biologie, la géochimie etc...

  3. CALiPER Application Summary Report 20. LED PAR38 Lamps

    SciTech Connect

    none,

    2012-11-01

    This report analyzes the independently tested photometric performance of 38 LED PAR38 lamps. The test results indicate substantial improvement versus earlier CALiPER testing of similar products, and performance comparable to recent data from LED Lighting Facts and ENERGY STAR. Additional testing that focuses on performance attributes beyond those covered by LM-79-08 is planned for this group of lamps, and will be presented in subsequent reports.

  4. La fracture de Hahn Steinthal traitée par vissage d'Herbert: 3 cas

    PubMed Central

    Bienvenu, Bouhelo-Pam Kevin Parfait; Amine, El Rhazi; Khalid, Chmali; Mohamed, Azarkane; Mohamed, El Idrissi; Mohamed, Shimi; Abdelhalim, El Ibrahimi; Abdelmajid, El Mrini

    2015-01-01

    Les fractures du capitulum sont rares. Leur prise en charge initiale doit être précoce et efficace en raison des risques engendrés sur le coude: rigidité, instabilité, arthrose. De nombreux traitements ont été proposés. Notre étude décrit le vissage par vis d'Herbert pratiqué chez trois patientes recensées entre 2012 et 2013. Elles ont été inclues selon les critères de traumatisme du coude avec douleur exquise externe avec un trait de fracture radiologique frontal du condyle huméral externe emportant la joue externe de la trochlée. Le diagnostic a été orienté par l'examen clinique et confirmé à la radiographie de face, de profil et des ¾ internes. Les lésions ont été classées selon Bryan et Morrey. Les patients ont été opérés en urgence par abord postéro-latéral de Kocher, réduction à ciel ouvert puis stabilisation par vis de Herbert enfouies. Le recul moyen a été de un an. La récupération fonctionnelle totale moyenne a été de 3,6 mois. L’évaluation fonctionnelle a été jugée excellente selon le score MEPI (Mayo Elbow Performance Index) pour les trois patients. Il n'y a pas eu de démontage de matériel. La consolidation osseuse moyenne a été de 2,6 mois. PMID:26015850

  5. Inflammation in Prostate Carcinogenesis: Role of the Tumor Suppressor Par-4

    DTIC Science & Technology

    2012-09-01

    which they coordinate with each other to form an intricate regula- tory network to protect against tumorigenesis. The Tumor Suppressor Par-4 at the...that integrates signals to coordinate molecular events that protect cells against tumorigenesis. Understanding the cross talks among each compo- nent...with the atypical isoforms of protein kinase C. Cell. 1996;86(5):777-86. 8. Sells SF, Wood DP, Jr., Joshi-Barve SS, Muthukumar S, Jacob RJ, Crist SA

  6. Seismic analysis of the Par Pond Dam: Study of slope failure and liquefaction. Technical evaluation report

    SciTech Connect

    Simos, N.; Reich, M.

    1994-07-01

    Stability concerns of the Par Pond Dam, an embankment structure in the Savannah River Site complex, resulted in a comprehensive evaluation of the state of its integrity. Specifically, excessive seepage through the embankment, slope failure due to an earthquake event as well as liquefaction potential of the embankment and the foundation are addressed and the potential of failure is evaluated. Lastly, remedial benefits of the addition of a berm structure are also assessed.

  7. Pars planitis is associated with an increased frequency of effector‐memory CD57+ T cells

    PubMed Central

    Pedroza‐Seres, Miguel; Linares, Marisela; Voorduin, Stephanie; Enrique, Rojas‐Ramos; Lascurain, Ricardo; Garfias, Yonathan; Jimenez‐Martinez, Maria Carmen

    2007-01-01

    Aim To evaluate the frequency, phenotype and the potential function of CD57+ T cell subsets in patients with pars planitis. Methods CD4+CD57+ and CD8+CD57+ T cells were quantitated in peripheral blood from 15 patients with pars planitis and 15 healthy controls. To evaluate the phenotype and potential function of CD57+ T cell subsets CCR7, CD27, CD28, CD45RA, CD45RO, intracellular IFN‐γ, IL‐4, perforin and granzyme‐A expression were assessed by flow cytometry. Results CD57+ T cells subsets were increased in patients with pars planitis (p = 0.002). The majority of CD4+CD57+ T cells were CCR7−CD27−CD28−CD45RO+, while the most CD8+CD57+ T cells were CCR7−CD27−CD28−CD45RA+. The number of cells positive for intracellular IFN‐γ and IL‐4 was higher in the CD57+ T cell populations. A greater number of CD8+CD57+ T cells than CD8+CD57− T cells were positive to perforin (p = 0.006) and granzyme‐A (p = 0.01). Conclusions CD57+ T cells had a phenotype associated with peripheral memory (CCR7−CD27−CD28−). Cytokine production by CD57+ T cells suggests that these cells may play a role in helper cell regulation. High expression of intracellular proteins involved in cytotoxicity suggests that CD8+CD57+ T cells may play an effector role. Taken together, this study proposes that CD57+ T cells function as memory‐effector T cell subsets during pars planitis pathogenesis. PMID:17475702

  8. Visual Outcomes and Prognostic Factors after Pars Plana Vitrectomy for Traumatic Endophthalmitis.

    PubMed

    Jiang, Tao; Jiang, Jing; Wang, Renping; Lei, Jianlin; Zhou, Yang

    2017-01-01

    Purpose. To evaluate visual outcomes and identify prognostic factors after pars plana vitrectomy (PPV) surgery for traumatic endophthalmitis. Methods. Medical records of 121 consecutive patients (121 eyes) diagnosed with traumatic endophthalmitis that had undergone pars plana vitrectomy were retrospectively reviewed. Results. 121 patients, aged from 6 to 71 years, all underwent PPV surgery. 113 cases had improved best corrected visual acuity (BCVA) after surgery and 60% of them obtained BCVA better than fingers counting (FC). Good final visual prognosis was significantly associated with time between trauma and initial treatment less than 12 hrs (40% versus 98%; P < 0.001), time between trauma and PPV treatment less than 24 hrs (62% versus 98%; P < 0.001), laceration length less than 10 mm (63% versus 96%; P < 0.001), and presenting VA better than LP (42% versus 96%; P < 0.001), while gender, type of laceration, presence of IOFB or retinal detachment, and the use of silicone oil tamponade were not significant factors resulting in better BCVA. Bacteria were identified in 43.8% of specimens and most of the microorganisms were identified as nonvirulent ones. Conclusions. Pars plana vitrectomy surgery was preferred as a primary treatment option for traumatic endophthalmitis. A good final visual prognosis was significantly associated with timely treatment, prompt vitrectomy surgery, shorter length of laceration, and better presenting visual acuity.

  9. Pituitary pars intermedia dysfunction (Equine Cushing's disease) in an onager (Equus hemionus onager).

    PubMed

    Peel, Alison J; Bouts, Tim; Flach, Edmund; Rivers, Sonja; Routh, Andrew

    2009-12-01

    Pituitary pars intermedia dysfunction (PPID), also known as Equine Cushing's disease, is most often diagnosed in older horses and ponies. To the authors' knowledge, there have been no reports of its diagnosis in captive nondomestic equids. A 13-yr old onager (Equus hemionus onager) at the Zoological Society of London (ZSL) Whipsnade Zoo showed clinical signs suggestive of PPID, including hirsutism, fat redistribution, weight loss, laminitis, and chronic infections. A dexamethasone suppression test was performed to confirm PPID. Subsequently, adenomatous hyperplasia and microadenoma of the pars intermedia were identified postmortem. Four months later, this onager's dam died suddenly, and adenomatous hyperplasia of the pars intermedia was diagnosed following necropsy. The dam had shown no clinical signs of PPID. Examination of archives identified eight other adult onagers that died or were euthanized between 1993 and 2007. The brain was not examined in four of these, but pituitary glands were described as enlarged during necropsy in three animals based on the subjective assessment of an experienced zoo and wildlife pathologist, making an overall prevalence of enlargement of 83.3%. Hyperplastic pituitary changes are positively correlated with age in domestic equids, and this may also be the case in onagers. Alternative etiologies are also discussed.

  10. K-Area and Par Pond Sewage Sludge Application Sites Groundwater Monitoring Report

    SciTech Connect

    Thompson, C.Y.

    1993-04-01

    During fourth quarter 1992, samples from the three monitoring wells at the K-Area site (KSS series) and the three monitoring wells at the Par Pond site (PSS series) were analyzed for constituents required by South Carolina Department of Health and Environmental Control Construction Permit 13, 173 and for other constituents as part of the Savannah River Site (SRS) Groundwater Monitoring Program. This report describes monitoring results that exceeded the final Primary Drinking Water Standards (PDWS) or the SRS flagging criteria. During fourth quarter 1992, no constituents analyzed exceeded the PDWS or the SRS Flag 2 criteria at the K-Area and Par Pond Sewage Sludge Application Sites. In the KSS well series, the field measurement for alkalinity ranged as high as 26 mg/L in well KSS 1D. Alkalinity measurements were zero in the PSS wells. Historical and current water-level elevations at the K-Area and Par Pond Sewage Sludge Application Site indicate that the groundwater flow directions are south to southwest (SRS grid coordinates).

  11. Impacts of active urea secretion into pars recta on urine concentration and urea excretion rate

    PubMed Central

    Layton, Anita T; Bankir, Lise

    2013-01-01

    It has been observed experimentally that early distal tubular urea flow exceeds urea delivery by the proximal convoluted tubule to the pars recta and loop of Henle. Moreover, the fractional excretion of urea in the urine may exceed values compatible with the reabsorption known to occur in the proximal convoluted tubule in the cortex. A likely explanation for these observations is that urea may be actively secreted into the pars recta, as proposed in a few studies. However, this hypothesis has yet to be demonstrated experimentally. In this study, we used a mathematical model of the renal medulla of the rat kidney to investigate the impacts of active urea secretion in the intrarenal handling of urea and in the urine concentrating ability. The model represents only the outer and inner medullary zones, with the actions taking place in the cortex incorporated via boundary conditions. Blood flow in the model vasculature is divided into plasma and red blood cell compartments. We compared urea flow rates and other related model variables without and with the hypothetical active urea secretion in the pars recta. The simulation suggests that active urea secretion induces a “urea-selective” improvement in urine concentrating ability by enhancing the efficiency of urea excretion without requiring a higher urine flow rate, and with only modest changes in the excretion of other solutes. These results should encourage experimental studies in order to assess the existence of an active urea secretion in the rodent kidney. PMID:24058732

  12. Visual Outcomes and Prognostic Factors after Pars Plana Vitrectomy for Traumatic Endophthalmitis

    PubMed Central

    2017-01-01

    Purpose. To evaluate visual outcomes and identify prognostic factors after pars plana vitrectomy (PPV) surgery for traumatic endophthalmitis. Methods. Medical records of 121 consecutive patients (121 eyes) diagnosed with traumatic endophthalmitis that had undergone pars plana vitrectomy were retrospectively reviewed. Results. 121 patients, aged from 6 to 71 years, all underwent PPV surgery. 113 cases had improved best corrected visual acuity (BCVA) after surgery and 60% of them obtained BCVA better than fingers counting (FC). Good final visual prognosis was significantly associated with time between trauma and initial treatment less than 12 hrs (40% versus 98%; P < 0.001), time between trauma and PPV treatment less than 24 hrs (62% versus 98%; P < 0.001), laceration length less than 10 mm (63% versus 96%; P < 0.001), and presenting VA better than LP (42% versus 96%; P < 0.001), while gender, type of laceration, presence of IOFB or retinal detachment, and the use of silicone oil tamponade were not significant factors resulting in better BCVA. Bacteria were identified in 43.8% of specimens and most of the microorganisms were identified as nonvirulent ones. Conclusions. Pars plana vitrectomy surgery was preferred as a primary treatment option for traumatic endophthalmitis. A good final visual prognosis was significantly associated with timely treatment, prompt vitrectomy surgery, shorter length of laceration, and better presenting visual acuity. PMID:28246599

  13. Modifications vibrationnelles induites par différentes vapeurs acides sur les polyanilines

    NASA Astrophysics Data System (ADS)

    Cochet, M.; Quillard, S.; Buisson, J. P.; Lefrant, S.; Louarn, G.

    1998-06-01

    We present a comparative study of conductive form of polyaniline, i.e, polyemeraldine doped with HCl vapor or with HCSA upon m-cresol vapor. UV-Vis.-nir absorption measurements on polyaniline thin films, vs acid vapors time exposure, have been made. In the same way, Raman spectra have been recorded with different excitation lines from the blue and red ranges to the infrared region. Finally, an assignment of Raman bands observed, is proposed and confirmed by vibrational calculations based on valence-force-field. Nous présentons une étude comparative de la forme conductrice de la polyaniline, c'est-à-dire de la polyéméraldine dopée par des vapeurs d'HCl ou dopée par l'acide camphre sulfonique (HCSA) sous vapeurs de m-crésol. Des mesures d'absorption UV-Vis-proche infrarouge sur des films minces de polyaniline, en fonction du temps d'exposition aux vapeurs acides, ont été réalisées. Parallèlement, les spectres Raman ont été obtenus pour différentes longueurs d'onde d'excitation allant du visible jusqu'au proche infrarouge. Finalement, une attribution des bandes Raman observées est proposée et confirmée par des calculs vibrationnels basés sur des champs de force de valence.

  14. Phosphorylation of LKB1/Par-4 Establishes Schwann Cell Polarity to Initiate and Control Myelin Extent

    PubMed Central

    Shen, Yun-An A.; Chen, Yan; Dao, Dang Q.; Mayoral, Sonia R.; Wu, Laiman; Meijer, Dies; Ullian, Erik M.; Chan, Jonah R.; Lu, Q. Richard

    2014-01-01

    The Schwann cell (SC)-axon interface represents a membrane specialization that integrates axonal signals to coordinate cytoskeletal dynamics resulting in myelination. Here we show that LKB1/Par-4 is asymmetrically localized to the SC-axon interface and colocalizes with the polarity protein Par-3. Using purified SCs and myelinating cocultures, we demonstrate that localization is dependent on the phosphorylation of LKB1 at serine-431. SC-specific deletion of LKB1 significantly attenuates developmental myelination, delaying the initiation and altering the myelin extent into adulthood, resulting in a 30% reduction in the conduction velocity along adult sciatic nerves. Phosphorylation of LKB1 by protein kinase A is essential to establish the asymmetric localization of LKB1 and Par-3 and rescues the delay in myelination observed in the SC-specific knockout of LKB1. Our findings suggest that SC polarity may coordinate multiple signaling complexes that couple SC-axon contact to the redistribution of specific membrane components necessary to initiate and control myelin extent. PMID:25255972

  15. Pars plana vitrectomy for malignant glaucoma in nonglaucomatous and in filtered glaucomatous eyes

    PubMed Central

    Matlach, Juliane; Slobodda, Joerg; Grehn, Franz; Klink, Thomas

    2012-01-01

    Purpose To assess the outcomes of pars plana vitrectomy for the treatment of malignant glaucoma in patients with and without previous filtration surgery. Patients and methods Data of 15 patients developing malignant glaucoma after trabeculectomy (60%) or following ophthalmic interventions other than filtration surgery (40%) were recorded retrospectively. Pars plana vitrectomy was performed in case of failed medical or laser treatment recreating the normal pathway of aqueous humor. The main outcome measures were the postoperative intraocular pressure (IOP), the frequency of complications, and success rate based on the following criteria: IOP reduction by ≥20% and to ≤21 mmHg (definition one) or an IOP < 18 mmHg (definition two) with (qualified success) and without (complete success) glaucoma medication. Results Vitrectomy reduced IOP from baseline in eyes with and without previous trabeculectomy during a median follow-up of 16.4 months (range 7 days to 58 months); although the majority of patients required glaucoma medication to reach desired IOP. The complete success rates were 11% (both definitions) for patients with filtering blebs and none of the patients without previous trabeculectomy had complete success at the 12-month visit. Complications were few and included transient shallowing of the anterior chamber, choroidal detachment, corneal decompensation, filtering bleb failure, and need for further IOP-lowering procedures. Conclusion Pars plana vitrectomy is equally effective for malignant glaucoma caused by trabeculectomy or interventions other than filtration surgery, although IOP-lowering medication is necessary in nearly all cases to maintain target IOP. PMID:23226000

  16. On PAR with PARP: cellular stress signaling through poly(ADP-ribose) and PARP-1

    PubMed Central

    Luo, Xin; Kraus, W. Lee

    2012-01-01

    Cellular stress responses are mediated through a series of regulatory processes that occur at the genomic, transcriptional, post-transcriptional, translational, and post-translational levels. These responses require a complex network of sensors and effectors from multiple signaling pathways, including the abundant and ubiquitous nuclear enzyme poly(ADP-ribose) (PAR) polymerase-1 (PARP-1). PARP-1 functions at the center of cellular stress responses, where it processes diverse signals and, in response, directs cells to specific fates (e.g., DNA repair vs. cell death) based on the type and strength of the stress stimulus. Many of PARP-1's functions in stress response pathways are mediated by its regulated synthesis of PAR, a negatively charged polymer, using NAD+ as a donor of ADP-ribose units. Thus, PARP-1's functions are intimately tied to nuclear NAD+ metabolism and the broader metabolic profile of the cell. Recent studies in cell and animal models have highlighted the roles of PARP-1 and PAR in the response to a wide variety of extrinsic and intrinsic stress signals, including those initiated by oxidative, nitrosative, genotoxic, oncogenic, thermal, inflammatory, and metabolic stresses. These responses underlie pathological conditions, including cancer, inflammation-related diseases, and metabolic dysregulation. The development of PARP inhibitors is being pursued as a therapeutic approach to these conditions. In this review, we highlight the newest findings about PARP-1's role in stress responses in the context of the historical data. PMID:22391446

  17. Higher incidence of Gastrospirillum sp. in swine with gastric ulcer of the pars oesophagea.

    PubMed

    Barbosa, A J; Silva, J C; Nogueira, A M; Paulino Júnior, E; Miranda, C R

    1995-03-01

    Gastric ulcer in swine is characterized by an area of acid-peptic digestion, occurs usually in the pars oesophagea of the stomach, and has unknown etiopathogenesis. The present work was carried out to investigate the prevalence of the newly described spiral-shaped microorganism Gastrospirillum sp. ("Gastrospirillum suis") in stomachs of abattoir pigs with and without gastric ulcer. Stomachs were removed from 32 consecutive pigs presenting apparently normal mucosa and from 32 additional consecutive pigs presenting frank, chronic gastric ulcer of the pars oesophagea. Fragments of antral, oxyntic, cardiac and pars oesophagea regions were taken from each stomach and processed for histology and for identification of Gastrospirillum sp. in tissue sections. The microorganisms were identified mainly in the mucous layer and in gastric foveolas of the antral and oxyntic mucosa. Forty pigs (62.5%) were positive for Gastrospirillum sp.; among them, 27 (67.5%) had gastric ulcer, and 13 (32.5%) had no ulcer. Twenty-four pigs (37.5%) were negative for Gastrospirillum sp.; among them, five (20.8%) presented with gastric ulcer, and 19 (79.2%) had no ulcer. There was a significant difference between pigs with and without gastric ulcer in regard to the presence of Gastrospirillum sp. (P < 0.01). The spiral-shaped microorganism Gastrospirillum sp. that inhabits the stomach of pigs should be considered a possible factor connected with the etiopathogenesis of swine gastric ulcer.

  18. Polycystin-1 binds Par3/aPKC and controls convergent extension during renal tubular morphogenesis

    NASA Astrophysics Data System (ADS)

    Castelli, Maddalena; Boca, Manila; Chiaravalli, Marco; Ramalingam, Harini; Rowe, Isaline; Distefano, Gianfranco; Carroll, Thomas; Boletta, Alessandra

    2013-10-01

    Several organs, including the lungs and kidneys, are formed by epithelial tubes whose proper morphogenesis ensures correct function. This is best exemplified by the kidney, where defective establishment or maintenance of tubular diameter results in polycystic kidney disease, a common genetic disorder. Most polycystic kidney disease cases result from loss-of-function mutations in the PKD1 gene, encoding Polycystin-1, a large receptor of unknown function. Here we demonstrate that PC-1 has an essential role in the establishment of correct tubular diameter during nephron development. Polycystin-1 associates with Par3 favouring the assembly of a pro-polarizing Par3/aPKC complex and it regulates a programme of cell polarity important for oriented cell migration and for a convergent extension-like process during tubular morphogenesis. Par3 inactivation in the developing kidney results in defective convergent extension and tubular morphogenesis, and in renal cyst formation. Our data define Polycystin-1 as central to cell polarization and to epithelial tube morphogenesis and homeostasis.

  19. Recuit thermique rapide de semi-conducteur par énergie micro-onde

    NASA Astrophysics Data System (ADS)

    Covas, M.; Gay, H. C.

    1993-05-01

    This paper proposes a new technique for rapid thermal annealing of semi-conductors. This technique is based on microwave energy, and offers the same advantages as the rapid thermal annealing by incoherent light, in terms of rapidity, and contamination. However, our technique reduces considerably the required energy for the annealing process. This technique has been compared to the rapid thermal by incoherent light: lab experiments, carried out on boron implanted silicon samples, showed that a power gain ratio of about 10 can be achieved. Nous proposons une méthode de recuit thermique rapide du silicium par énergie micro-onde. Cette technique offre les mêmes avantages que les traitements thermiques rapides par lumière incohérente, c'est-à-dire des durées de chauffage très brèves, limitant ainsi la diffusion des dopants, et un traitement plaquette par plaquette : les risques de contamination de tout un lot sont ainsi éliminés. De plus notre méthode requiert une faible énergie : pour parvenir à des recuits de qualité similaire à celle obtenue dans des fours de recuit rapide à lampes il faut un flux de puissance 10 fois plus faible.

  20. MPDZ EXPRESSION IN THE CAUDOLATERAL SUBSTANTIA NIGRA PARS RETICULATA IS CRUCIALLY INVOLVED IN ALCOHOL WITHDRAWAL

    PubMed Central

    Kruse, L.C.; Walter, N.A.R.; Buck, K.J.

    2014-01-01

    Association studies implicate the multiple PDZ domain protein (MUPP1/MPDZ) gene in risk for alcoholism in humans and alcohol withdrawal in mice. Although manipulation of the Mpdz gene by homologous recombination and bacterial artificial chromosome transgenesis has suggested that its expression affects alcohol withdrawal risk, the potential confounding effects of linked genes and developmental compensation currently limit interpretation. Here, using RNA interference, we directly test the impact of Mpdz expression on alcohol withdrawal severity and provide brain regional mechanistic information. Lentiviral-mediated delivery of Mpdz short hairpin RNA (shRNA) to the caudolateral substantia nigra pars reticulata significantly reduces Mpdz expression and exacerbates alcohol withdrawal convulsions compared to control mice delivered a scrambled shRNA. Neither baseline nor pentylenetetrazol enhanced convulsions differed between Mpdz shRNA and control animals, indicating that Mpdz expression in the caudolateral substantia nigra pars reticulata does not generally affect seizure susceptibility. To our knowledge, these represent the first in vivo Mpdz RNA interference analyses, and provide the first direct evidence that Mpdz expression impacts behavior. Our results confirm that Mpdz is a quantitative trait gene for alcohol withdrawal and demonstrate that its expression in the caudolateral substantia nigra pars reticulata is crucially involved in risk for alcohol withdrawal. PMID:25109596

  1. Approaching Long Genomic Regions and Large Recombination Rates with msParSm as an Alternative to MaCS

    PubMed Central

    Montemuiño, Carlos; Espinosa, Antonio; Moure, Juan C.; Vera, Gonzalo; Hernández, Porfidio; Ramos-Onsins, Sebastián

    2016-01-01

    The msParSm application is an evolution of msPar, the parallel version of the coalescent simulation program ms, which removes the limitation for simulating long stretches of DNA sequences with large recombination rates, without compromising the accuracy of the standard coalescence. This work introduces msParSm, describes its significant performance improvements over msPar and its shared memory parallelization details, and shows how it can get better, if not similar, execution times than MaCS. Two case studies with different mutation rates were analyzed, one approximating the human average and the other approximating the Drosophila melanogaster average. Source code is available at https://github.com/cmontemuino/msparsm. PMID:27721650

  2. Genome-wide protein QTL mapping identifies human plasma kallikrein as a post-translational regulator of serum uPAR levels.

    PubMed

    Portelli, Michael A; Siedlinski, Mateusz; Stewart, Ceri E; Postma, Dirkje S; Nieuwenhuis, Maartje A; Vonk, Judith M; Nurnberg, Peter; Altmuller, Janine; Moffatt, Miriam F; Wardlaw, Andrew J; Parker, Stuart G; Connolly, Martin J; Koppelman, Gerard H; Sayers, Ian

    2014-02-01

    The soluble cleaved urokinase plasminogen activator receptor (scuPAR) is a circulating protein detected in multiple diseases, including various cancers, cardiovascular disease, and kidney disease, where elevated levels of scuPAR have been associated with worsening prognosis and increased disease aggressiveness. We aimed to identify novel genetic and biomolecular mechanisms regulating scuPAR levels. Elevated serum scuPAR levels were identified in asthma (n=514) and chronic obstructive pulmonary disease (COPD; n=219) cohorts when compared to controls (n=96). In these cohorts, a genome-wide association study of serum scuPAR levels identified a human plasma kallikrein gene (KLKB1) promoter polymorphism (rs4253238) associated with serum scuPAR levels in a control/asthma population (P=1.17 × 10(-7)), which was also observed in a COPD population (combined P=5.04 × 10(-12)). Using a fluorescent assay, we demonstrated that serum KLKB1 enzymatic activity was driven by rs4253238 and is inverse to scuPAR levels. Biochemical analysis identified that KLKB1 cleaves scuPAR and negates scuPAR's effects on primary human bronchial epithelial cells (HBECs) in vitro. Chymotrypsin was used as a proproteolytic control, while basal HBECs were used as a control to define scuPAR-driven effects. In summary, we reveal a novel post-translational regulatory mechanism for scuPAR using a hypothesis-free approach with implications for multiple human diseases.

  3. PAR-2, LGL-1 and the CDC-42 GAP CHIN-1 act in distinct pathways to maintain polarity in the C. elegans embryo.

    PubMed

    Beatty, Alexander; Morton, Diane G; Kemphues, Kenneth

    2013-05-01

    In the one-cell C. elegans embryo, polarity is maintained by mutual antagonism between the anterior cortical proteins PAR-3, PKC-3, PAR-6 and CDC-42, and the posterior cortical proteins PAR-2 and LGL-1 on the posterior cortex. The mechanisms by which these proteins interact to maintain polarity are incompletely understood. In this study, we investigate the interplay among PAR-2, LGL-1, myosin, the anterior PAR proteins and CDC-42. We find that PAR-2 and LGL-1 affect cortical myosin accumulation by different mechanisms. LGL-1 does not directly antagonize the accumulation of cortical myosin and instead plays a role in regulating PAR-6 levels. By contrast, PAR-2 likely has separate roles in regulating cortical myosin accumulation and preventing the expansion of the anterior cortical domain. We also provide evidence that asymmetry of active CDC-42 can be maintained independently of LGL-1 and PAR-2 by a redundant pathway that includes the CDC-42 GAP CHIN-1. Finally, we show that, in addition to its primary role in regulating the size of the anterior cortical domain via its binding to PAR-6, CDC-42 has a secondary role in regulating cortical myosin that is not dependent on PAR-6.

  4. Remote estimation of Kd (PAR) using MODIS and Landsat imagery for turbid inland waters in Northeast China

    NASA Astrophysics Data System (ADS)

    Song, Kaishan; Ma, Jianhang; Wen, Zhidan; Fang, Chong; Shang, Yingxin; Zhao, Ying; Wang, Ming; Du, Jia

    2017-01-01

    Light availability for photosynthetically active radiation (PAR) is one of the major factors governing photosynthesis in aquatic ecosystems. Conventional measurements of light attenuation in the PAR domain (Kd(PAR)) is representative for only small areas of water body. Remotely sensed optical imagery can be utilized to monitor Kd(PAR) in large areas of water bodies, based on the relationship between water leaving radiance and Kd(PAR). In this study, six field surveys were conducted over 20 lakes (or reservoirs) across Northeast China from April to September 2015. In order to derive the Kd(PAR) at regional scale, the Landsat/TM/ETM+/OLI and the MODIS daily surface reflectance data (MOD09GA ∼500 m, Bands 1-7) were used to establish empirical inversion models. Through multiple stepwise regression analysis, the band difference (Red-Blue) and band ratio (NIR/Red) were used in Landsat imagery modeling, and the band difference (Red-Blue) and ratio (Red/Blue) were used in MODIS imagery modeling. The accuracy of the two models was evaluated by 10-fold cross-validation in ten times. The results indicate that the models performed well for both Landsat (R2 = 0.83, RMSE = 0.95, and MRE = 0.33), and MODIS (R2 = 0.86, RMSE = 0.91, and MRE = 0.19) imagery. However, the Kd(PAR) derived by MODIS is slightly higher than that estimated by Landsat (slope = 1.203 and R2 = 0.972). Consistency of model performance between the MODIS daily (MYD09G A) and the 8-Day composite reflectance (MYD09A1) data was verified by Kd(PAR) estimations and regression analysis (slope = 1.044 and R2 = 0.966). Finally, the spatial and temporal distribution of Kd(PAR) in Northeast China indicated that specific geographical characteristics as well as meteorological alterations can influence Kd(PAR) calibrations. Specifically, we have revealed that the wind speed and algal bloom are the major determinants of Kd(PAR) in Lake Hulun (2050 km2) and Xingkai (4412 km2).

  5. Disentangling the confounding effects of PAR and air temperature on net ecosystem exchange in time and scale

    NASA Astrophysics Data System (ADS)

    yang, Z.; Chen, J.; Becker, R.; Chu, H.; Xie, J.; Shao, C.

    2013-12-01

    Net ecosystem exchange of CO2 (NEE) in temperate forests is modulated by microclimatic factors. The effects of those factors differ at different time scales and during different time periods. Some of them are correlated across a number of time scales, so their effects on NEE are confounded by each other. PAR and air temperature (Ta) are among the two most important drivers of NEE in temperate forests, and among the two most correlated microclimatic factors. PAR and Ta have similar daily, seasonal, and annual cycles. Their influence on NEE is confounded by each other and entangled together especially at those scales. In this study, we tried to disentangle the confounding effects of them on NEE at different time scales and during different time periods. To accomplish this objective, we applied the innovative spectral analysis techniques including Continuous Wavelet Transformation (CWT), Cross Wavelet Transformation (XWT), Wavelet Coherent (WTC), and Partial Wavelet Coherence (PWC) on seven years time series (2004-2010) of PAR, Ta and NEE from the Ohio Oak Openings site (N 41.5545°, W 83.8438°), USA for spectral analysis. We found that PAR is the major driver at short time scales (e.g. semidiurnal and daily) and Ta is the major driver at long time scales (e.g. seasonal and annual). At daily scale during growing seasons, PAR is anti-phase with NEE with no time delay while Ta lagged PAR about 2-3 hours, which could be explained by the strong dependence of photosynthesis on PAR and a 2-3 hours lags of the daily course of Ta to PAR. At daily scale during non-growing season, NEE has little variation and thus neither Ta nor PAR has high common wavelet power and significant coherence with NEE. At annual scale, Ta is anti-phase with NEE and PAR leads NEE about 34 days, which could be explained by the strong dependence of LAI dynamics on Ta and the lag between the LAI/biomass development and the progress of sunlight. We also found that NEE distributes most of its variation

  6. Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex

    PubMed Central

    Roll, Patrice; Vernes, Sonja C.; Bruneau, Nadine; Cillario, Jennifer; Ponsole-Lenfant, Magali; Massacrier, Annick; Rudolf, Gabrielle; Khalife, Manal; Hirsch, Edouard; Fisher, Simon E.; Szepetowski, Pierre

    2010-01-01

    It is a challenge to identify the molecular networks contributing to the neural basis of human speech. Mutations in transcription factor FOXP2 cause difficulties mastering fluent speech (developmental verbal dyspraxia, DVD), whereas mutations of sushi-repeat protein SRPX2 lead to epilepsy of the rolandic (sylvian) speech areas, with DVD or with bilateral perisylvian polymicrogyria. Pathophysiological mechanisms driven by SRPX2 involve modified interaction with the plasminogen activator receptor (uPAR). Independent chromatin-immunoprecipitation microarray screening has identified the uPAR gene promoter as a potential target site bound by FOXP2. Here, we directly tested for the existence of a transcriptional regulatory network between human FOXP2 and the SRPX2/uPAR complex. In silico searches followed by gel retardation assays identified specific efficient FOXP2-binding sites in each of the promoter regions of SRPX2 and uPAR. In FOXP2-transfected cells, significant decreases were observed in the amounts of both SRPX2 (43.6%) and uPAR (38.6%) native transcripts. Luciferase reporter assays demonstrated that FOXP2 expression yielded a marked inhibition of SRPX2 (80.2%) and uPAR (77.5%) promoter activity. A mutant FOXP2 that causes DVD (p.R553H) failed to bind to SRPX2 and uPAR target sites and showed impaired down-regulation of SRPX2 and uPAR promoter activity. In a patient with polymicrogyria of the left rolandic operculum, a novel FOXP2 mutation (p.M406T) was found in the leucine-zipper (dimerization) domain. p.M406T partially impaired the FOXP2 regulation of SRPX2 promoter activity, whereas that of the uPAR promoter remained unchanged. Together with recently described FOXP2-CNTNAP2 and SRPX2/uPAR links, the FOXP2-SRPX2/uPAR network provides exciting insights into molecular pathways underlying speech-related disorders. PMID:20858596

  7. Protease-Activated Receptor 2 (PAR2) Is Upregulated by Acanthamoeba Plasminogen Activator (aPA) and Induces Proinflammatory Cytokine in Human Corneal Epithelial Cells

    PubMed Central

    Tripathi, Trivendra; Abdi, Mahshid; Alizadeh, Hassan

    2014-01-01

    Purpose. Acanthamoeba plasminogen activator (aPA) is a serine protease elaborated by Acanthamoeba trophozoites that facilitates the invasion of trophozoites to the host and contributes to the pathogenesis of Acanthamoeba keratitis (AK). The aim of this study was to explore if aPA stimulates proinflammatory cytokine in human corneal epithelial (HCE) cells via the protease-activated receptors (PARs) pathway. Methods. Acanthamoeba castellanii trophozoites were grown in peptone-yeast extract glucose for 7 days, and the supernatants were collected and centrifuged. The aPA was purified using the fast protein liquid chromatography system, and aPA activity was determined by zymography assays. Human corneal epithelial cells were incubated with or without aPA (100 μg/mL), PAR1 agonists (thrombin, 10 μM; TRAP-6, 10 μM), and PAR2 agonists (SLIGRL-NH2, 100 μM; AC 55541, 10 μM) for 24 and 48 hours. Inhibition of PAR1 and PAR2 involved preincubating the HCE cells for 1 hour with the antagonist of PAR1 (SCH 79797, 60 μM) and PAR2 (FSLLRY-NH2, 100 μM) with or without aPA. Human corneal epithelial cells also were preincubated with PAR1 and PAR2 antagonists and then incubated with or without PAR1 agonists (thrombin and TRAP-6) and PAR2 agonists (SLIGRL-NH2 and AC 55541). Expression of PAR1 and PAR2 was examined by quantitative RT-PCR (qRT-PCR), flow cytometry, and immunocytochemistry. Interleukin-8 expression was quantified by qRT-PCR and ELISA. Results. Human corneal epithelial cells constitutively expressed PAR1 and PAR2 mRNA. Acanthamoeba plasminogen activator and PAR2 agonists significantly upregulated PAR2 mRNA expression (1- and 2-fold, respectively) (P < 0.05). Protease-activated receptor 2 antagonist significantly inhibited aPA, and PAR2 agonists induced PAR2 mRNA expression in HCE cells (P < 0.05). Protease-activated receptor 1 agonists, but not aPA, significantly upregulated PAR1 mRNA expression, which was significantly inhibited by PAR1 antagonist in HCE cells

  8. Effet Hall et Magnetisme des Alliages Amorphes Nickel-Zirconium Fabriques Par Pulverisation

    NASA Astrophysics Data System (ADS)

    Morel, Robert

    Cette these se situe dans le cadre d'une etude des proprietes electroniques et structurales des alliages metalliques amorphes, en cours depuis quelques annees a l'Universite de Montreal. Ce programme nous a entre autres amene a caracteriser la magnetoresistivite et l'effet Hall d'alliages FeZr, CoZr et NiZr, ce qui a permis de mettre en evidence deux caracteristiques de l'effet Hall: Dans les alliages amorphes ferromagnetiques, la resistivite elevee engendre un effet Hall extraordinaire beaucoup plus important que celui enregistre dans les metaux cristallins. La polarisation des spins entrai ne une asymetrie de la diffusion qui, tant dans les phases cristalline et amorphe, est tenue responsable de cette contribution. L'autre particularite du comportement de Hall de ces systemes est le renversement de signe du coefficient de Hall ordinaire, qui passe du negatif au positif dans les echantillons plus riches en zirconium. Dans les metaux cristallins, un modele d'electrons libres predit un signe negatif a moins que la conduction ne soit dominee par les trous. Or, dans un milieu desordonne les memes concepts sont difficilement applicables et de nouvelles theories ont du etre elaborees pour expliquer ce phenomene. Jusqu'a maintenant, l'etude des alliages amorphes nickel-zirconium s'est faite surtout a partir d'echantillons fabriques par trempe sur roue. Malheureusement cette technique ne permet pas la fabrication d'alliages contenant plus de 70% de nickel, a l'exception du seul compose Ni _{90}Zr_{10 }. Pour pallier a cette lacune et etendre nos connaissance a l'ensemble de la gamme de compositions, nous avons fabrique par pulverisation cathodique des echantillons NiZr amorphes--et quelques alliages cristallins tres riches en nickel--couvrant une bonne partie de la gamme interdite par la technique de trempe sur roue. Dans un premier temps, par comparaison avec les resultats connus nous avons mis en evidence les similitudes et les differences entre les alliages obtenus par

  9. Apparent PS II absorption cross-section and estimation of mean PAR in optically thin and dense suspensions of Chlorella.

    PubMed

    Klughammer, Christof; Schreiber, Ulrich

    2015-01-01

    Theoretical prediction of effective mean PAR in optically dense samples is complicated by various optical effects, including light scattering and reflections. Direct information on the mean rate of photon absorption by PS II is provided by the kinetics of the fluorescence rise induced upon onset of strong actinic illumination (O-I1 rise). A recently introduced kinetic multi-color PAM fluorometer was applied to study the relationship between initial slope and cell density in the relatively simple model system of suspensions of Chlorella. Use of a curve fitting routine was made which was originally developed for assessment of the wavelength-dependent absorption cross-section of PS II, σ II(λ), in dilute suspensions. The model underlying analysis of the O-I1 rise kinetics is outlined and data on the relationship between fitted values of σ II(λ) and PAR in dilute samples are presented. With increasing cell density, lowering of apparent cross-section, <σ>(λ), with respect to σ II(λ), relates to a decrease of effective mean PAR, <PAR>(λ), relative to incident PAR(λ). When ML and AL are applied in the same direction, the decline of <σ>(λ)/σ II(λ) with increasing optical density is less steep than that of the theoretically predicted <PAR>(λ)/PAR(λ). It approaches a value of 0.5 when the same colors of ML and AL are used, in agreement with theory. These observations open the way for estimating mean PAR in optically dense samples via measurements of <σ>(λ)/σ II(λ)).

  10. Peroxynitrite-induced thymocyte apoptosis: the role of caspases and poly (ADP-ribose) synthetase (PARS) activation.

    PubMed Central

    Virág, L; Scott, G S; Cuzzocrea, S; Marmer, D; Salzman, A L; Szabó, C

    1998-01-01

    The mechanisms by which immature thymocyte apoptosis is induced during negative selection are poorly defined. Reports demonstrated that cross-linking of T-cell receptor leads to stromal cell activation, expression of inducible nitric oxide synthase (iNOS) and, subsequently, to thymocyte apoptosis. Therefore we examined, whether NO directly or indirectly, through peroxynitrite formation, causes thymocyte apoptosis. Immuno-histochemical detection of nitrotyrosine revealed in vivo peroxynitrite formation in the thymi of naive mice. Nitrotyrosine, the footprint of peroxynitrite, was predominantly found in the corticomedullary junction and the medulla of naive mice. In the thymi of mice deficient in the inducible isoform of nitric oxide synthase, considerably less nitrotyrosine was found. Exposure of thymocytes in vitro to low concentrations (10 microM) of peroxynitrite led to apoptosis, whereas higher concentrations (50 microM) resulted in intense cell death with the characteristics of necrosis. We also investigated the effect of poly (ADP-ribose) synthetase (PARS) inhibition on thymocyte apoptosis. Using the PARS inhibitor 3-aminobenzamide (3-AB), or thymocytes from PARS-deficient animals, we established that PARS determines the fate of thymocyte death. Suppression of cellular ATP levels, and the cellular necrosis in response to peroxynitrite were prevented by PARS inhibition. Therefore, in the absence of PARS, cells are diverted towards the pathway of apoptotic cell death. Similar results were obtained with H2O2 treatment, while apoptosis induced by non-oxidative stimuli such as dexamethasone or anti-FAS antibody was unaffected by PARS inhibition. In conclusion, we propose that peroxynitrite-induced apoptosis may play a role in the process of thymocyte negative selection. Furthermore, we propose that the physiological role of PARS cleavage by apopain during apoptosis may serve as an energy-conserving step, enabling the cell to complete the process of apoptosis

  11. Hypersensitivity Induced by Activation of Spinal Cord PAR2 Receptors Is Partially Mediated by TRPV1 Receptors

    PubMed Central

    Mrozkova, Petra; Spicarova, Diana; Palecek, Jiri

    2016-01-01

    Protease-activated receptors 2 (PAR2) and transient receptor potential vanilloid 1 (TRPV1) receptors in the peripheral nerve endings are implicated in the development of increased sensitivity to mechanical and thermal stimuli, especially during inflammatory states. Both PAR2 and TRPV1 receptors are co-expressed in nociceptive dorsal root ganglion (DRG) neurons on their peripheral endings and also on presynaptic endings in the spinal cord dorsal horn. However, the modulation of nociceptive synaptic transmission in the superficial dorsal horn after activation of PAR2 and their functional coupling with TRPV1 is not clear. To investigate the role of spinal PAR2 activation on nociceptive modulation, intrathecal drug application was used in behavioural experiments and patch-clamp recordings of spontaneous, miniature and dorsal root stimulation-evoked excitatory postsynaptic currents (sEPSCs, mEPSCs, eEPSCs) were performed on superficial dorsal horn neurons in acute rat spinal cord slices. Intrathecal application of PAR2 activating peptide SLIGKV-NH2 induced thermal hyperalgesia, which was prevented by pretreatment with TRPV1 antagonist SB 366791 and was reduced by protein kinases inhibitor staurosporine. Patch-clamp experiments revealed robust decrease of mEPSC frequency (62.8 ± 4.9%), increase of sEPSC frequency (127.0 ± 5.9%) and eEPSC amplitude (126.9 ± 12.0%) in dorsal horn neurons after acute SLIGKV-NH2 application. All these EPSC changes, induced by PAR2 activation, were prevented by SB 366791 and staurosporine pretreatment. Our results demonstrate an important role of spinal PAR2 receptors in modulation of nociceptive transmission in the spinal cord dorsal horn at least partially mediated by activation of presynaptic TRPV1 receptors. The functional coupling between the PAR2 and TRPV1 receptors on the central branches of DRG neurons may be important especially during different pathological states when it may enhance pain perception. PMID:27755539

  12. Row orientation effect on UV-B, UV-A and PAR solar irradiation components in vineyards at Tuscany, Italy

    NASA Astrophysics Data System (ADS)

    Grifoni, D.; Carreras, G.; Zipoli, G.; Sabatini, F.; Dalla Marta, A.; Orlandini, S.

    2008-11-01

    Besides playing an essential role in plant photosynthesis, solar radiation is also involved in many other important biological processes. In particular, it has been demonstrated that ultraviolet (UV) solar radiation plays a relevant role in grapevines ( Vitis vinifera) in the production of certain important chemical compounds directly responsible for yield and wine quality. Moreover, the exposure to UV-B radiation (280-320 nm) can affect plant-disease interaction by influencing the behaviour of both pathogen and host. The main objective of this research was to characterise the solar radiative regime of a vineyard, in terms of photosynthetically active radiation (PAR) and UV components. In this analysis, solar spectral UV irradiance components, broadband UV (280-400 nm), spectral UV-B and UV-A (320-400 nm), the biological effective UVBE, as well as the PAR (400-700 nm) component, were all considered. The diurnal patterns of these quantities and the UV-B/PAR and UV-B/UV-A ratios were analysed to investigate the effect of row orientation of the vineyard in combination with solar azimuth and elevation angles. The distribution of PAR and UV irradiance at various heights of the vertical sides of the rows was also studied. The results showed that the highest portion of plants received higher levels of daily radiation, especially the UV-B component. Row orientation of the vines had a pronounced effect on the global PAR received by the two sides of the rows and, to a lesser extent, UV-A and UV-B. When only the diffused component was considered, this geometrical effect was greatly attenuated. UV-B/PAR and UV-A/PAR ratios were also affected, with potential consequences on physiological processes. Because of the high diffusive capacity of the UV-B radiation, the UV-B/PAR ratio was significantly lower on the plant portions exposed to full sunlight than on those in the shade.

  13. Structure par RMN d'un complexe AlcR(1-60)-ADN: Reconnaissance du petit sillon par la partie N-terminale

    NASA Astrophysics Data System (ADS)

    Cahuzac, B.; Félenbok, B.; Guittet, E.

    1999-10-01

    Aspergillus nidulans is a filamentous fungus able to use ethanol as sole energy source. The activation of the ethanol regulon genes expression is mediated by the AlcR protein. Its DNA-binding domain is located in the N-terminus (residues 1 to 60), and its NMR solution structure shows a global zinc binuclear cluster fold, with two helices in addition to the basic binuclear motif. A small number of crystallographic structures of DNA complexes of binuclear cluster proteins is yet known, and points out the major groove and the first helix as the principal sites of interaction on the DNA and the protein respectively. In this article we show evidences that the N-terminus of the protein is involved in binding to the minor groove. Aspergillus nidulans est un champignon filamenteux capable d'utiliser l'éthanol comme source unique d'énergie. La protéine AlcR est responsable de l'activation de l'expression des gènes du régulon éthanol. Le domaine de liaison à l'ADN est situé dans la partie N-terminale de la protéine (a.a. 1 à 60), et sa structure déterminée par RMN en solution montre un repliement global en bouquet binucléaire à zinc, avec deux hélices supplémentaires par rapport au motif de base. Alors que les structures déjà connues de complexes ADN - bouquets binucléaires permettent de situer dans le grand sillon la quasi-totalité des interactions, nous montrons dans la présente étude l'implication du début de la séquence dans la reconnaissance du petit sillon de l'ADN (a.a. 5 et 6).

  14. Proteinase-activated receptor 2 (PAR(2)) in cholangiocarcinoma (CCA) cells: effects on signaling and cellular level.

    PubMed

    Kaufmann, Roland; Hascher, Alexander; Mussbach, Franziska; Henklein, Petra; Katenkamp, Kathrin; Westermann, Martin; Settmacher, Utz

    2012-12-01

    In this study, we demonstrate functional expression of the proteinase-activated receptor 2 (PAR(2)), a member of a G-protein receptor subfamily in primary cholangiocarcinoma (PCCA) cell cultures. Treatment of PCCA cells with the serine proteinase trypsin and the PAR(2)-selective activating peptide, furoyl-LIGRLO-NH(2), increased migration across a collagen membrane barrier. This effect was inhibited by a PAR(2)-selective pepducin antagonist peptide (P2pal-18S) and it was also blocked with the Met receptor tyrosine kinase (Met) inhibitors SU 11274 and PHA 665752, the MAPKinase inhibitors PD 98059 and SL 327, and the Stat3 inhibitor Stattic. The involvement of Met, p42/p44 MAPKinases and Stat3 in PAR(2)-mediated PCCA cell signaling was further supported by the findings that trypsin and the PAR(2)-selective agonist peptide, 2-furoyl-LIGRLO-NH(2), stimulated activating phosphorylation of these signaling molecules in cholangiocarcinoma cells. With our results, we provide a novel signal transduction module in cholangiocarcinoma cell migration involving PAR(2)-driven activation of Met, p42/p44 MAPKinases and Stat3.

  15. Store-operated CRAC channels regulate PAR2-activated Ca2+ signaling and cytokine production in airway epithelial cells

    PubMed Central

    Jairaman, Amit; Yamashita, Megumi; Schleimer, Robert P.; Prakriya, Murali

    2015-01-01

    The G-protein coupled protease-activated receptor 2 (PAR2) plays an important role in the pathogenesis of various inflammatory and auto-immune disorders. In airway epithelial cells (AECs), stimulation of PAR2 by allergens and proteases triggers the release of a host of inflammatory mediators to regulate bronchomotor tone and immune cell recruitment. Activation of PAR2 turns on several cell signaling pathways of which the mobilization of cytosolic Ca2+ is likely a critical but poorly understood event. Here, we show that Ca2+ release-activated Ca2+ (CRAC) channels encoded by STIM1 and Orai1 are a major route of Ca2+ entry in primary human AECs and drive the Ca2+ elevations seen in response to PAR2 activation. Activation of CRAC channels induces the production of several key inflammatory mediators from AECs including TSLP, IL-6 and PGE2, in part through stimulation of gene expression via NFAT (nuclear factor of activated T-cells). Furthermore, PAR2 stimulation induces the production of many key inflammatory mediators including PGE2, IL-6, IL-8 and GM-CSF in a CRAC-channel dependent manner. These findings indicate that CRAC channels are the primary mechanism for Ca2+ influx in AECs and a vital checkpoint for the induction of PAR2-induced proinflammatory cytokines. PMID:26238490

  16. Protease Activated Receptor 2 (PAR2) Induces Long-Term Depression in the Hippocampus through Transient Receptor Potential Vanilloid 4 (TRPV4)

    PubMed Central

    Shavit-Stein, Efrat; Artan-Furman, Avital; Feingold, Ekaterina; Ben Shimon, Marina; Itzekson-Hayosh, Zeev; Chapman, Joab; Vlachos, Andreas; Maggio, Nicola

    2017-01-01

    Protease activated receptors (PARs) are involved in regulating synaptic transmission and plasticity in the brain. While it is well-accepted that PAR1 mediates long-term potentiation (LTP) of excitatory synaptic strength, the role of PAR2 in synaptic plasticity remains not well-understood. In this study, we assessed the role of PAR2-signaling in plasticity at hippocampal Schaffer collateral-CA1 synapses. Using field potential recordings, we report that PAR2-activation leads to long-term depression (LTD) of synaptic transmission through a protein kinase A -dependent, Transient Receptor Potential Vanilloid 4 -mediated mechanism, which requires the activation of N-methyl-D-aspartate receptors. These results demonstrate that the effects of PAR2 on synaptic plasticity are distinct from what is observed upon PAR1-activation. Thus, we propose that the activation of different classes of PARs, i.e., PAR1 and PAR2, may set the threshold of synaptic plasticity in the hippocampal network by balancing LTP and LTD. PMID:28303089

  17. Bazooka/PAR3 is dispensable for polarity in Drosophila follicular epithelial cells.

    PubMed

    Shahab, Jaffer; Tiwari, Manu D; Honemann-Capito, Mona; Krahn, Michael P; Wodarz, Andreas

    2015-03-13

    Apico-basal polarity is the defining characteristic of epithelial cells. In Drosophila, apical membrane identity is established and regulated through interactions between the highly conserved Par complex (Bazooka/Par3, atypical protein kinase C and Par6), and the Crumbs complex (Crumbs, Stardust and PATJ). It has been proposed that Bazooka operates at the top of a genetic hierarchy in the establishment and maintenance of apico-basal polarity. However, there is still ambiguity over the correct sequence of events and cross-talk with other pathways during this process. In this study, we reassess this issue by comparing the phenotypes of the commonly used baz(4) and baz(815-8) alleles with those of the so far uncharacterized baz(XR11) and baz(EH747) null alleles in different Drosophila epithelia. While all these baz alleles display identical phenotypes during embryonic epithelial development, we observe strong discrepancies in the severity and penetrance of polarity defects in the follicular epithelium: polarity is mostly normal in baz(EH747) and baz(XR11) while baz(4) and baz(815) (-8) show loss of polarity, severe multilayering and loss of epithelial integrity throughout the clones. Further analysis reveals that the chromosomes carrying the baz(4) and baz(815-8) alleles may contain additional mutations that enhance the true baz loss-of-function phenotype in the follicular epithelium. This study clearly shows that Baz is dispensable for the regulation of polarity in the follicular epithelium, and that the requirement for key regulators of cell polarity is highly dependent on developmental context and cell type.

  18. A prospective study on postoperative discomfort after 20-gauge pars plana vitrectomy

    PubMed Central

    Yu, Ji-guo; Ni, Fang; Xiang, Yi; Feng, Yi-fan; Wang, Jue; Fu, Xun-an

    2015-01-01

    Purpose To evaluate postoperative pain and other irritation symptoms after 20-gauge (20G) pars plana vitrectomy. Materials and methods A total of 110 consecutive patients were enrolled in our studies, and 87 patients who underwent the conventional 20G pars plana vitrectomy were included in the final analysis. All vitrectomies were performed using the same surgical technique by the same surgeon. Patients were examined before surgery and 1 day, 3 days, 7 days, 1 month, and 2 months postoperatively. The main outcome measures include patient age and sex, intraocular pressure (IOP), ocular pain, pain score, pain medication use, and other irritation symptoms comprising itching, foreign body sensation, burning, photophobia, and dryness. The pain was evaluated using the Numerical Rating Scale scored from 0 to 10. Results Postoperative pain was relatively common during the first day after surgery, as it was reported by 43 (49.4%) patients. Then, the prevalence gradually decreased to eleven (12.6%) patients at 2 months. Most patients reported mild or moderate pain, with a pain score of 1–5, but only four patients were given analgesics for ocular pain. A postoperative rise of IOP was noted in 25 patients at day 1. Most of these patients with high IOP reported moderate pain. Other ocular irritation symptoms were varied after surgery. There was still one-quarter of patients that had foreign body sensation and dryness symptoms at month 2 after surgery. Conclusion Mild and moderate ocular pain were relatively common after 20G vitrectomy, which is more often associated with elevated IOP. Other irritation symptoms were also presented after surgery and could affect the life quality of patients. Therefore, the discomforts after 20G pars plana vitrectomy should be of concern, and timely management should be provided as part of routine postoperative care. PMID:26244010

  19. Topography of dyskinesias and torticollis evoked by inhibition of substantia nigra pars reticulata.

    PubMed

    Dybdal, David; Forcelli, Patrick A; Dubach, Mark; Oppedisano, Michael; Holmes, Angela; Malkova, Ludise; Gale, Karen

    2013-04-01

    GABAergic neurons of the substantia nigra pars reticulata (SNpr) and globus pallidus pars interna (GPi) constitute the output pathways of the basal ganglia. In monkeys, choreiform limb dyskinesias have been described after inhibition of the GPi, but not the SNpr. Given the anatomical and functional similarities between these structures, we hypothesized that choreiform dyskinesias could be evoked by inhibition of an appropriate region within the SNpr. The GABAA receptor agonist, muscimol, was infused into various sites within the SNpr and the adjacent STN of freely moving macaques. The effect of the GABAA antagonist, bicuculline (BIC), was also examined. Muscimol (MUS) in SNpr evoked the following: (1) choreiform dyskinesias of the contralateral arm and/or leg from central and lateral sites; (2) contralaterally directed torticollis from central and posterior sites; and (3) contraversive quadrupedal rotation from anterior and lateral sites. MUS infusions into the adjacent SN pars compacta or STN were without effect, ruling out a contribution of drug spread to adjacent structures. BIC in SNpr induced ipsiversive postures without choreiform dyskinesia or torticollis, whereas in the STN, it evoked ballistic movements. This is the first report of choreiform dyskinesia evoked by inhibition of the SNpr. This highly site-specific effect was obtained from a restricted region within the SNpr distinct from that responsible for inducing torticollis. These results suggest that overactivity of different SNpr outputs mediates choreiform dyskinesia and torticollis. These abnormalities are symptoms of dystonia, Huntington's disease, and iatrogenic dyskinesias, suggesting that these conditions may result, in part, from a loss of function in SNpr efferent projections.

  20. Vasodilator-Stimulated Phosphoprotein Deficiency Potentiates PAR-1-induced Increase in Endothelial Permeability in Mouse Lungs

    PubMed Central

    Profirovic, Jasmina; Han, Jingyan; Andreeva, Alexandra V.; Neamu, Radu F.; Pavlovic, Sasha; Vogel, Stephen M.; Walter, Ulrich; Voyno-Yasenetskaya, Tatyana A.

    2010-01-01

    Vasodilator-stimulated phosphoprotein (VASP) is implicated in the protection of the endothelial barrier in vitro and in vivo. VASP function in thrombin signaling in the endothelial cells (ECs) is not known. For the first time we studied the effects of VASP deficiency on EC permeability and pulmonary vascular permeability in response to thrombin receptor stimulation. We provided the evidence that VASP deficiency potentiates the increase in endothelial permeability induced by activation of thrombin receptor in cultured human umbilical vein endothelial cells (HUVECs) and isolated mouse lungs. Using transendothelial resistance measurement, we showed that siRNA-mediated VASP downregulation in HUVECs leads to a potentiation of thrombin- and protease-activated receptor 1 (PAR-1) agonist-induced increase in endothelial permeability. Compared to control cells, VASP-deficient HUVECs had delayed endothelial junctional reassembly and abrogated VE-cadherin cytoskeletal anchoring in the recovery phase after thrombin stimulation, as demonstrated by immunofluorescence studies and cell fractionation analysis, respectively. Measurement of the capillary filtration coefficient in isolated mouse lungs demonstrated that VASP−/− mice have increased microvascular permeability in response to infusion with PAR-1 agonist compared to wild type mice. Lack of VASP led to decreased Rac1 activation both in VASP-deficient HUVECs after thrombin stimulation and VASP−/− mouse lungs after PAR-1 agonist infusion, indicating that VASP effects on thrombin signaling may correlated with changes in Rac1 activity. This study demonstrates that VASP may play critical and complex role in the regulation of thrombin-dependent disruption of the endothelial barrier function. PMID:20945373

  1. Peptide binding properties of the three PDZ domains of Bazooka (Drosophila Par-3).

    PubMed

    Yu, Cao Guo; Tonikian, Raffi; Felsensteiner, Corinna; Jhingree, Jacquelyn R; Desveaux, Darrell; Sidhu, Sachdev S; Harris, Tony J C

    2014-01-01

    The Par complex is a conserved cell polarity regulator. Bazooka/Par-3 is scaffold for the complex and contains three PDZ domains in tandem. PDZ domains can act singly or synergistically to bind the C-termini of interacting proteins. Sequence comparisons among Drosophila Baz and its human and C. elegans Par-3 counterparts indicate a divergence of the peptide binding pocket of PDZ1 and greater conservation for the pockets of PDZ2 and PDZ3. However, it is unclear whether the domains from different species share peptide binding preferences, or if their tandem organization affects their peptide binding properties. To investigate these questions, we first used phage display screens to identify unique peptide binding profiles for each single PDZ domain of Baz. Comparisons with published phage display screens indicate that Baz and C. elegans PDZ2 bind to similar peptides, and that the peptide binding preferences of Baz PDZ3 are more similar to C. elegans versus human PDZ3. Next we quantified the peptide binding preferences of each Baz PDZ domain using single identified peptides in surface plasmon resonance assays. In these direct binding studies, each peptide had a binding preference for a single PDZ domain (although the peptide binding of PDZ2 was weakest and the least specific). PDZ1 and PDZ3 bound their peptides with dissociation constants in the nM range, whereas PDZ2-peptide binding was in the µM range. To test whether tandem PDZ domain organization affects peptide binding, we examined a fusion protein containing all three PDZ domains and their normal linker regions. The binding strengths of the PDZ-specific peptides to single PDZ domains and to the PDZ domain tandem were indistinguishable. Thus, the peptide binding pockets of each PDZ domain in Baz are not obviously affected by the presence of neighbouring PDZ domains, but act as isolated modules with specific in vitro peptide binding preferences.

  2. Ensemble Kalman Filter Data Assimilation with the ParFlow Hydrologic Model

    NASA Astrophysics Data System (ADS)

    Williams, J. L., III

    2015-12-01

    Hydrometeorological research has shown that simulations of atmospheric processes benefit from sophisticated land surface formulations. Moisture and energy fluxes between the land surface and lower atmosphere are influenced strongly not only by atmospheric conditions, but by terrestrial hydrologic processes, soil moisture distribution in particular. By improving the representation of hydrologic processes, better predictive skill can be achieved in a fully-coupled weather forcasting model. Further improvements in the model can be realized by incorporating observed data values into the hydrologic model. This work applies the Ensemble Kalman Filter functionality included in the Data Assimilation Assimilation Research Testbed (DART), a collection of data assimilation tools maintained at the National Center for Atmospheric Research, to the ParFlow hydrologic model—the hydrologic component of the TerrSysMP fully coupled hydrologic - land surface - atmospheric model system. This generalized data assimilation tool allows observations of variables in the hydrologic component of the system to be incorporated into the overall error covariance matrix thus guiding the development of quantities that define the model state. Single dimension column tests, and a three-dimensional idealized catchment drainage and dry-out test were performed with the ParFlow-DART system to evaluate the effects of assimilating pressure head, soil moisture, and outflow observations on the development of the model through time. The data assimilation system was then applied to the hydrologic portion a fully-coupled (subsurface, land surface, and atmosphere) simulation over the North Rhine-Westphalia region in western Germany to demonstrate the utility of this system in a non-idealized and realistic forecasting situation. The success of these tests will allow the ParFlow-DART system to be developed into a complete data assimilation package for the TerrSysMP fully-coupled modeling system.

  3. Ensemble Kalman Filter Data Assimilation for the ParFlow Hydrologic Model

    NASA Astrophysics Data System (ADS)

    Williams, John

    2014-05-01

    Research in hydrometeorology has demonstrated repeatedly that atmospheric models benefit from detailed formulations of the land surface, and that energy and moisture fluxes between the land surface and atmosphere are coupled strongly not only with atmospheric conditions, but also with subsurface hydrology—particularly soil moisture distribution. Improving the representation of hydrologic processes should lead to better predictive skill in a fully-coupled weather forecasting model, and the hydrologic model itself can be improved by incorporating observed data values. For this work, we apply the Ensemble Kalman Filter functionality included in the Data Assimilation Assimilation Research Testbed (DART), a collection of data assimilation tools maintained at the National Center for Atmospheric Research, to the ParFlow hydrologic model—the hydrologic component of the TerrSysMP fully coupled hydrologic - land surface - atmospheric model system. This generalized data assimilation tool allows observations of variables in the hydrologic component of the system to be incorporated into the overall error covariance matrix thus guiding the development of quantities that define the model state. Single dimension column tests, two-dimensional hillslope tests, and a three-dimensional drainage and dry-out test were performed with the ParFlow-DART system to evaluate the effects of assimilating pressure head, soil moisture, and outflow observations on the development of the model through time. The success of these tests will allow the ParFlow-DART system to be developed into a complete data assimilation package for the TerrSysMP fully-coupled modeling system.

  4. Helicobacter pylori CagA Inhibits PAR1-MARK Family Kinases by Mimicking Host Substrates

    SciTech Connect

    Nesic, D.; Miller, M; Quinkert, Z; Stein, M; Chait, B; Stebbins, C

    2010-01-01

    The CagA protein of Helicobacter pylori interacts with numerous cellular factors and is associated with increased virulence and risk of gastric carcinoma. We present here the cocrystal structure of a subdomain of CagA with the human kinase PAR1b/MARK2, revealing that a CagA peptide mimics substrates of this kinase family, resembling eukaryotic protein kinase inhibitors. Mutagenesis of conserved residues central to this interaction renders CagA inactive as an inhibitor of MARK2.

  5. Enquete sur les aspects toxicologiques de la phytotherapie utilisee par un herboriste à Fes, Maroc

    PubMed Central

    Zeggwagh, Ali Amine; Lahlou, Younes; Bousliman, Yassir

    2013-01-01

    Introduction Dans le but d'étudier l'aspect toxicologique des plantes médicinales utilisées en médecine traditionnelle, une étude ethnobotanique a été réalisée à la ville de Fès au centre du Maroc. Méthodes Ont été inclus dans l'étude tous les patients ayant bénéficié d'une prescription par l'herboriste de plantes à visée thérapeutique. La discussion de nos résultats s'est faite sur la base d'une revue de la littérature avec identification des principales plantes toxiques utilisées en phytothérapie au Maroc. L'approche bibliographique a permis de compléter les informations. Résultats L'âge moyen des patients traités par des plantes (38 femmes, 32 hommes) était de 35 ± 18 ans. L'enquête ethnobotanique à révélé que la majorité des plantes médicinales étaient utilisées contre les affections urinaires (21%), suivi des maladies de l'appareil digestif (19.6%) et des maladies rhumatologiques (18.2%). Le nombre de plantes prescrits par l'herboriste a été de 53 dont 5 sont potentiellement toxiques. L'identification taxonomique des plantes prescrites a recensé 30 familles dont les plus représentées sont les Lamiaceae (23.33%), les Apiaceae (13,33%) et les Asteraceae (10%). La prescription des plantes considérées comme toxiques a concerné 7,1% des consultants traités par les plantes médicinales. Aucune complication inhérente aux plantes prescrites n'a été déplorée. Conclusion Malgré les résultats encourageants de notre enquête sur le compte de la phytothérapie, la pratique de la phytothérapie est laissée à la vulgarisation et à l'oubli scientifique, législatif et universitaire. PMID:23734270

  6. Dispositifs opto-électropiques à commande par coordonnées

    NASA Astrophysics Data System (ADS)

    Smovge, A. K.

    1994-06-01

    The approach has been explained theoretically and experimentally considering analog coordinate-controlled optoelectronic devices as an alternative to custom potentiometers and variable resistors, whose potentially unreliable element, a wiping electromechanical contact, is eliminated through the use of an optoelectronic conversion principle. The new designs have been proposed and requirements for discrete-continuous photoresistor structure have been determined by using both simple numeric and analytical models for a realization of the coordinate dependence of the output voltage and internal resistance with predetermined accuracy. The new type of optoelectronic coordinate-controlled delay line of millisecond-range pulsed signals have been proposed as well as the design of two-dimensional sensor of displacements. The new method for upgradding the noise immunity, based on the use of the photoconductivity response time dependence from the illuminance have been proposed. Une direction de recherches a été justifiée théoriquement et expérimentalement. Cette étude considère les dipositifs opto-électroniques à commande par coordonnées comme une alternative aux potentiomètres classiques dont l'élément défaillant éventuel, à savoir le contact électrique mobile de frottement, est supprimé par l'emploi d'une méthode de conversion optoélectronique. La nouvelle construction a été proposée et les exigences concernant la structure photorésistance discret-continu ont été déterminées par l'emploi des deux méthodes de calcul numérique et analytique. De nouvelles structures du dispositif de retard des signaux impulsionnels dans la gamme des millisecondes avec une durée de retard réglable à commande par coordonnées aussi bien que du vidéocapteur positionnel bidimensionnel sont proposées. Une nouvelle méthode de l'augmentation de sensibilité de ce vidéocapteur aux obstacles optiques, basée sur la dépendance du temps de la photoréponse du niveau d

  7. Comprehensive Cooling Water Study: Volume 7, Ecology of Par Pond, Savannah River Plant: Final report

    SciTech Connect

    Wilde, E.W.

    1987-10-01

    The Comprehensive Cooling Water Study (CCWS) was initiated in 1983 to evaluate the environmental effects of the intake and release of cooling water on the structure and function of aquatic ecosystems at the Savannah River Plant. The initial report (Gladden et al., 1985) described the results from the first year of the study. This document is the final report and concludes the program. The report comprises eight volumes. The first is a summary of environmental effects. The other seven volumes address water quality, radionuclide and heavy metal transport, wetlands, aquatic ecology, Federally endangered species, ecology of Par Pond, and waterfowl. 222 refs., 31 figs., 67 tabs.

  8. Laser UV à semiconducteur nitrure pompé par des micropointes

    NASA Astrophysics Data System (ADS)

    Barjon, J.; Adelmann, C.; Baptist, R.; Brault, J.; Daudin, B.; Dang, Le Si; Molva, E.

    2002-06-01

    Dans un Laser à Semiconducteur Micropointes (LSM), le milieu amplificateur est pompé par un faisceau d'électrons issus de micropointes effet de champ. Ce type de laser est particulièrement adapté aux semi-conducteurs à grands gaps tels que les nitrures GaN et AIN émettant dans l'UltraViolet, pour lesquels le dopage et la prise de contact ohmique deviennent problématiques. Ce papier présente ce dispositif et l'état d'avancement des travaux.

  9. Photoémission de Csl induite par une impulsion laser intense femtoseconde

    NASA Astrophysics Data System (ADS)

    Belsky, A.; Vasil'Ev, A.; Yatsenko, B.; Bachau, H.; Martin, P.; Geoffroy, G.; Guizard, S.

    2003-06-01

    Nous avons mesuré pour la première fois les spectres de photoélectrons émis par un cristal isolant à large bande interdite, Csl, avec une dynamique de 10^6 coups/s, excité par la source laser haute cadence du C.E.L.I.A (800 nm, 40 fs, 1 kHz, 1 TW). L'émission d'électrons jusqu'à des énergies de quelques dizaines d'électrons-volts a été observée pour des impulsions d'éclairement compris entre 0.5 et 3 TW/cm^2, relativement faible donc par comparaison aux éclairements utilisés pour accélérer les électrons d'un atome aux mêmes énergies. Ces spectres contiennent tous, en particulier, deux bandes dans le domaine des basses énergies d'électrons (<5 eV), également observées lors d'études précédentes. Les électrons les plus énergétiques forment un plateau intense légèrement structuré et limité par une coupure exponentielle. Pour des impulsions de 3 TW/cm^2 cette coupure est située à 27 eV. L'insuffisance du mécanisme électron-photon-phonon, considéré jusqu'à présent comme le principal processus d'échauffement des électrons dans les solides en interaction non destructrice avec un champ laser, nous a poussé à proposer un mécanisme alternatif. Ce modèle met en évidence les transitions directes multiphotoniques dans la bande de conduction du solide qui sont incontournables du fait de sa structure électronique multi-branches

  10. Peptide-Based Optical uPAR Imaging for Surgery: In Vivo Testing of ICG-Glu-Glu-AE105

    PubMed Central

    Juhl, Karina; Christensen, Anders; Persson, Morten; Ploug, Michael; Kjaer, Andreas

    2016-01-01

    Near infrared intra-operative optical imaging is an emerging technique with clear implications for improved cancer surgery by enabling a more distinct delineation of the tumor margins during resection. This modality has the potential to increase the number of patients having a curative radical tumor resection. In the present study, a new uPAR-targeted fluorescent probe was developed and the in vivo applicability was evaluated in a human xenograft mouse model. Most human carcinomas express high level of uPAR in the tumor-stromal interface of invasive lesions and uPAR is therefore considered an ideal target for intra-operative imaging. Conjugation of the flourophor indocyanine green (ICG) to the uPAR agonist (AE105) provides an optical imaging ligand with sufficiently high receptor affinity to allow for a specific receptor targeting in vivo. For in vivo testing, human glioblastoma xenograft mice were subjected to optical imaging after i.v. injection of ICG-AE105, which provided an optimal contrast in the time window 6–24 h post injection. Specificity of the uPAR-targeting probe ICG-AE105 was demonstrated in vivo by 1) no uptake of unconjugated ICG after 15 hours, 2) inhibition of ICG-AE105 tumor uptake by a bolus injection of the natural uPAR ligand pro-uPA, and finally 3) the histological colocalization of ICG-AE105 fluorescence and immunohistochemical detected human uPAR on resected tumor slides. Taken together, our data supports the potential use of this probe for intra-operative optical guidance in cancer surgery to ensure complete removal of tumors while preserving adjacent, healthy tissue. PMID:26828431

  11. Photosynthesis of Littorella uniflora grown under two PAR regimes: C3 and CAM gas exchange and the regulation of internal CO2 and O2 concentrations.

    PubMed

    Robe, W E; Griffiths, H

    1990-11-01

    The submersed aquatic macrophyte Littorella uniflora was grown under 50 and 300 μmol m(-2) s(-1) photosynthetically active radiation (PAR) (low and high PAR regimes) but identical sediment CO2 supply (1.0 mol m(-3)). The interactions between plant morphology, whole plant CO2 and O2 exchange, CAM activity, [CO2] i and [O2] i have been investigated in comparison with in vitro CO2 and PAR response characteristics (using 1 mm leaf sections). In terms of morphology, high-PAR-grown plants were smaller and leaves contained less chlorophyll, although root growth was proportionally larger. Gas exchange fluxes over roots and shoots of intact plants were similar in direction under the two PAR regimes, with the majority of CO2 uptake via the roots. Photosynthetic O2 evolution from intact plants was greater in high-PAR-grown L. uniflora (2.18 compared with 1.49 μmol O2g(-1) fresh weight h(-1) for the low PAR regime). Although net daytime CO2 uptake was similar for both PAR regimes (0.79 and 0.75 μmol g(-1) fwt h(-1)), net dark CO2 uptake was at a higher rate (0.92 compared with 0.52 μmol CO2 g(-1) fwt h(-1)), and dark fixation (as malic acid) was threefold greater in high PAR plants (ΔH(+) 117 compared with 42 μmol H(+) g(-1) fwt). Comparison of dark CO2 uptake with dark fixation suggested that much of the CO2 fixed at night and regenerated during the day may be respiratory in origin (60% low PAR plants, 71% high PAR plants). Regeneration of CO2 from CAM could account for 62% of daytime CO2 supply in low PAR plants and 81% in high PAR plants. [CO2] i values (ranging from 0.42 to 1.03 mol m(-3)) were close to or above the concentration required to saturate photosynthesis in vitro (0.5 mol m(-3)) under both PAR regimes, and combined with the low [O2] i (2.6-4.3 mol m(-3)) should have suppressed photorespiration. However, PAR inside leaves would have been well below the in vitro light saturation requirement (850-1000 μmol m(-2) s(-1) for both treatments). Thus PAR rather

  12. Étude comparative des techniques d'analyse par fluorescence X à dispersion d'énergie (ED-XRF) et à dispersion de longueur d'onde (WD-XRF), et par spectrométrie d'émission atomique à source plasma couplée par induction (ICP-AES)

    NASA Astrophysics Data System (ADS)

    Rahmani, A.; Benyaïch, F.; Bounakhla, M.; Bilal, E.; Moutte, J.; Gruffat, J. J.; Zahry, F.

    2004-11-01

    Dans ce travail, nous présentons une étude comparative des techniques d'analyse par fluorescence X à dispersion d'énergie (ED-XRF) et à dispersion de longueur d'onde (WD-XRF), et par spectrométrie d'émission atomique à source plasma couplée par induction (ICP-AES). Les résultats de la calibration des spectromètres à dispersion d'énergie, à excitation par sources radioactives (55Fe, 109Cd et 241Am) et à excitation secondaire (cible secondaire Mo et Cu) du Centre National pour l'Energie, les Sciences et les Techniques Nucléaires (CNESTEN, Rabat, Maroc) sur des échantillons étalons de références de l'Agence International de l'Energie Atomique (AIEA) et du Community Bureau of Référence (BCR) ont été comparés aux résultats d'analyse des mêmes échantillons étalons par la spectrométrie X à dispersion de longueur d'onde (WD-XRF) et par spectrométrie d'émission atomique à source plasma couplé par induction (ICP-AES) au département GENERIC du centre SPIN à l'Ecole des Mines de Saint-Etienne (France). Les trois techniques d'analyse utilisées donnent des résultats comparables pour le dosage des éléments majeurs, alors que pour les traces on note des déviations importantes à cause des effets de matrice qui sont difficiles à corriger dans le cas de la fluorescence X.

  13. Melanoma cell therapy: Endothelial progenitor cells as shuttle of the MMP12 uPAR-degrading enzyme

    PubMed Central

    Laurenzana, Anna; Biagioni, Alessio; D'Alessio, Silvia; Bianchini, Francesca; Chillà, Anastasia; Margheri, Francesca; Luciani, Cristina; Mazzanti, Benedetta; Pimpinelli, Nicola; Torre, Eugenio; Danese, Silvio; Calorini, Lido; Rosso, Mario Del; Fibbi, Gabriella

    2014-01-01

    The receptor for the urokinase-type plasminogen activator (uPAR) accounts for many features of cancer progression, and is therefore considered a target for anti-tumoral therapy. Only full length uPAR mediates tumor progression. Matrix-metallo-proteinase-12 (MMP12)-dependent uPAR cleavage results into the loss of invasion properties and angiogenesis. MMP12 can be employed in the field of “targeted therapies” as a biological drug to be delivered directly in patient's tumor mass. Endothelial Progenitor Cells (EPCs) are selectively recruited within the tumor and could be used as cellular vehicles for delivering anti-cancer molecules. The aim of our study is to inhibit cancer progression by engeneering ECFCs, a subset of EPC, with a lentivirus encoding the anti-tumor uPAR-degrading enzyme MMP12. Ex vivo manipulated ECFCs lost the capacity to perform capillary morphogenesis and acquired the anti-tumor and anti-angiogenetic activity. In vivo MMP12-engineered ECFCs cleaved uPAR within the tumor mass and strongly inhibited tumor growth, tumor angiogenesis and development of lung metastasis. The possibility to exploit tumor homing and activity of autologous MMP12-engineered ECFCs represents a novel way to combat melanoma by a “personalized therapy”, without rejection risk. The i.v. injection of radiolabelled MMP12-ECFCs can thus provide a new theranostic approach to control melanoma progression and metastasis. PMID:25003596

  14. Association between mutations in gyrA and parC genes of Acinetobacter baumannii clinical isolates and ciprofloxacin resistance

    PubMed Central

    Ardebili, Abdollah; Lari, Abdolaziz Rastegar; Beheshti, Maryam; Lari, Elnaz Rastegar

    2015-01-01

    Objective(s): We investigated the contribution of gyrA and parC mutational mechanism in decreased ciprofloxacin susceptibility of Acinetobacter baumannii isolated from burn wound infections. Materials and Methods: Ciprofloxacin susceptibility of 50 A. baumannii isolates was evaluated by disk diffusion and agar dilution methods. PCR and sequencing were performed for detection of mutation in gyrA and parC genes. Results: The 44 and 4 isolates of A. baumannii exhibited full and intermediate-resistant to ciprofloxacin, respectively. Overall, the 42 isolates with double mutations of gyrA and parC genes showed a higher level of ciprofloxacin resistance than the 3 isolates with single mutations of gyrA or parC. Conclusion: Simultaneous mutations in gyrA and parC genes are expected to play a major role in high-level fluoroquinolone resistance in A. baumannii; albeit a single mutation in DNA topoisomerase IV could occasionally be associated with intermediate-resistance to these antimicrobials. PMID:26221488

  15. Melanoma cell therapy: Endothelial progenitor cells as shuttle of the MMP12 uPAR-degrading enzyme.

    PubMed

    Laurenzana, Anna; Biagioni, Alessio; D'Alessio, Silvia; Bianchini, Francesca; Chillà, Anastasia; Margheri, Francesca; Luciani, Cristina; Mazzanti, Benedetta; Pimpinelli, Nicola; Torre, Eugenio; Danese, Silvio; Calorini, Lido; Del Rosso, Mario; Fibbi, Gabriella

    2014-06-15

    The receptor for the urokinase-type plasminogen activator (uPAR) accounts for many features of cancer progression, and is therefore considered a target for anti-tumoral therapy. Only full length uPAR mediates tumor progression. Matrix-metallo-proteinase-12 (MMP12)-dependent uPAR cleavage results into the loss of invasion properties and angiogenesis. MMP12 can be employed in the field of "targeted therapies" as a biological drug to be delivered directly in patient's tumor mass. Endothelial Progenitor Cells (EPCs) are selectively recruited within the tumor and could be used as cellular vehicles for delivering anti-cancer molecules. The aim of our study is to inhibit cancer progression by engeneering ECFCs, a subset of EPC, with a lentivirus encoding the anti-tumor uPAR-degrading enzyme MMP12. Ex vivo manipulated ECFCs lost the capacity to perform capillary morphogenesis and acquired the anti-tumor and anti-angiogenetic activity. In vivo MMP12-engineered ECFCs cleaved uPAR within the tumor mass and strongly inhibited tumor growth, tumor angiogenesis and development of lung metastasis. The possibility to exploit tumor homing and activity of autologous MMP12-engineered ECFCs represents a novel way to combat melanoma by a "personalized therapy", without rejection risk. The i.v. injection of radiolabelled MMP12-ECFCs can thus provide a new theranostic approach to control melanoma progression and metastasis.

  16. Par@Graph - a parallel toolbox for the construction and analysis of large complex climate networks

    NASA Astrophysics Data System (ADS)

    Ihshaish, H.; Tantet, A.; Dijkzeul, J. C. M.; Dijkstra, H. A.

    2015-10-01

    In this paper, we present Par@Graph, a software toolbox to reconstruct and analyze complex climate networks having a large number of nodes (up to at least 106) and edges (up to at least 1012). The key innovation is an efficient set of parallel software tools designed to leverage the inherited hybrid parallelism in distributed-memory clusters of multi-core machines. The performance of the toolbox is illustrated through networks derived from sea surface height (SSH) data of a global high-resolution ocean model. Less than 8 min are needed on 90 Intel Xeon E5-4650 processors to reconstruct a climate network including the preprocessing and the correlation of 3 × 105 SSH time series, resulting in a weighted graph with the same number of vertices and about 3.2 × 108 edges. In less than 14 min on 30 processors, the resulted graph's degree centrality, strength, connected components, eigenvector centrality, entropy and clustering coefficient metrics were obtained. These results indicate that a complete cycle to construct and analyze a large-scale climate network is available under 22 min Par@Graph therefore facilitates the application of climate network analysis on high-resolution observations and model results, by enabling fast network reconstruct from the calculation of statistical similarities between climate time series. It also enables network analysis at unprecedented scales on a variety of different sizes of input data sets.

  17. Par@Graph - a parallel toolbox for the construction and analysis of large complex climate networks

    NASA Astrophysics Data System (ADS)

    Ihshaish, H.; Tantet, A.; Dijkzeul, J. C. M.; Dijkstra, H. A.

    2015-01-01

    In this paper, we present Par@Graph, a software toolbox to reconstruct and analyze complex climate networks having a large number of nodes (up to at least O (106)) and of edges (up to at least O (1012)). The key innovation is an efficient set of parallel software tools designed to leverage the inherited hybrid parallelism in distributed-memory clusters of multi-core machines. The performance of the toolbox is illustrated through networks derived from sea surface height (SSH) data of a global high-resolution ocean model. Less than 8 min are needed on 90 Intel Xeon E5-4650 processors to construct a climate network including the preprocessing and the correlation of 3 × 105 SSH time series, resulting in a weighted graph with the same number of vertices and about 3 × 106 edges. In less than 5 min on 30 processors, the resulted graph's degree centrality, strength, connected components, eigenvector centrality, entropy and clustering coefficient metrics were obtained. These results indicate that a complete cycle to construct and analyze a large-scale climate network is available under 13 min. Par@Graph therefore facilitates the application of climate network analysis on high-resolution observations and model results, by enabling fast network construction from the calculation of statistical similarities between climate time series. It also enables network analysis at unprecedented scales on a variety of different sizes of input data sets.

  18. Late-Onset Inadvertent Bleb Formation following Pars Plana M3 Molteno Implant Tube Obstruction

    PubMed Central

    Abdul-Rahman, Anmar M.; Molteno, Anthony

    2017-01-01

    Purpose To report a case of inadvertent bleb formation presenting 18 months after pars plana M3 Molteno implant tube obstruction in a patient with mixed mechanism glaucoma. Materials and Methods An 84-year-old Caucasian male with mixed mechanism glaucoma underwent slit-lamp examination, gonioscopy, colour anterior segment photography and anterior segment optical coherence tomography (AS-OCT). Results An inadvertent bleb developed 18 months after pars plana impl