47 resultados para deformed odd-odd nucleus
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Gait freezing is an episodic arrest of locomotion due to an inability to take normal steps. Pedunculopontine nucleus stimulation is an emerging therapy proposed to improve gait freezing, even where refractory to medication. However, the efficacy and precise effects of pedunculopontine nucleus stimulation on Parkinsonian gait disturbance are not established. The clinical application of this new therapy is controversial and it is unknown if bilateral stimulation is more effective than unilateral. Here, in a double-blinded study using objective spatiotemporal gait analysis, we assessed the impact of unilateral and bilateral pedunculopontine nucleus stimulation on triggered episodes of gait freezing and on background deficits of unconstrained gait in Parkinson’s disease. Under experimental conditions, while OFF medication, Parkinsonian patients with severe gait freezing implanted with pedunculopontine nucleus stimulators below the pontomesencephalic junction were assessed during three conditions; off stimulation, unilateral stimulation and bilateral stimulation. Results were compared to Parkinsonian patients without gait freezing matched for disease severity and healthy controls. Pedunculopontine nucleus stimulation improved objective measures of gait freezing, with bilateral stimulation more effective than unilateral. During unconstrained walking, Parkinsonian patients who experience gait freezing had reduced step length and increased step length variability compared to patients without gait freezing; however, these deficits were unchanged by pedunculopontine nucleus stimulation. Chronic pedunculopontine nucleus stimulation improved Freezing of Gait Questionnaire scores, reflecting a reduction of the freezing encountered in patients’ usual environments and medication states. This study provides objective, double-blinded evidence that in a specific subgroup of Parkinsonian patients, stimulation of a caudal pedunculopontine nucleus region selectively improves gait freezing but not background deficits in step length. Bilateral stimulation was more effective than unilateral.
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I knew a woman who lived by herself in a white brick house near the light house at Watson’s Bay. As she grew older, and her memory played tricks, she started to collect odd things. At breakfast each morning, she pulled the stickers off fruits—apples and pears and mandarins—and stuck them to her shoes. When she finished a meal, she stacked the dirty dishes on the couch in her sun room. In spring, when her garden bloomed, she cut orchids from their stems and arranged them in bowls of water around the house. When she ran out of bowls, she used butter containers instead...
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Circoviruses lack an autonomous DNA polymerase and are dependent on the replication machinery of the host cell for de novo DNA synthesis. Accordingly, the viral DNA needs to cross both the plasma membrane and the nuclear envelope before replication can occur. Here we report on the subcellular distribution of the beak and feather disease virus (BFDV) capsid protein (CP) and replication-associated protein (Rep) expressed via recombinant baculoviruses in an insect cell system and test the hypothesis that the CP is responsible for transporting the viral genome, as well as Rep, across the nuclear envelope. The intracellular localization of the BFDV CP was found to be directed by three partially overlapping bipartite nuclear localization signals (NLSs) situated between residues 16 and 56 at the N terminus of the protein. Moreover, a DNA binding region was also mapped to the N terminus of the protein and falls within the region containing the three putative NLSs. The ability of CP to bind DNA, coupled with the karyophilic nature of this protein, strongly suggests that it may be responsible for nuclear targeting of the viral genome. Interestingly, whereas Rep expressed on its own in insect cells is restricted to the cytoplasm, coexpression with CP alters the subcellular localization of Rep to the nucleus, strongly suggesting that an interaction with CP facilitates movement of Rep into the nucleus. Copyright © 2006, American Society for Microbiology. All Rights Reserved.
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Since the discovery of the first receptor tyrosine kinase (RTK) proteins in the late 1970s and early 1980s, many scientists have explored the functions of these important cell signaling molecules. The finding that these proteins are often deregulated or mutated in diseases such as cancers and diabetes, together with their potential as clinical therapeutic targets, has further highlighted the necessity for understanding the signaling functions of these important proteins. The mechanisms of RTK regulation and function have been recently reviewed by Lemmon & Schlessinger (2010) but in this review we instead focus on the results of several recent studies that show receptor tyrosine kinases can function from subcellular localisations, including in particular the nucleus, in addition to their classical plasma membrane location. Nuclear localisation of receptor tyrosine kinases has been demonstrated to be important for normal cell function but is also believed to contribute to the pathogenesis of several human diseases.
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This collaborative project by Daniel Mafe and Andrew Brown, one of a number in they have been involved in together, conjoins painting and digital sound into a single, large scale, immersive exhibition/installation. The work as a whole acts as an interstitial point between contrasting approaches to abstraction: the visual and aural, the digital and analogue are pushed into an alliance and each works to alter perceptions of the other. For example, the paintings no longer mutely sit on the wall to be stared into. The sound seemingly emanating from each work shifts the viewer’s typical visual perception and engages their aural sensibilities. This seems to make one more aware of the objects as objects – the surface of each piece is brought into scrutiny – and immerses the viewer more viscerally within the exhibition. Similarly, the sonic experience is focused and concentrated spatially by each painted piece even as the exhibition is dispersed throughout the space. The sounds and images are similar in each local but not identical, even though they may seem to be the same from casual interaction, closer attention will quickly show this is not the case. In preparing this exhibition each artist has had to shift their mode of making to accommodate the other’s contribution. This was mainly done by a process of emptying whereby each was called upon to do less to the works they were making and to iterate the works toward a shared conception, blurring notions of individual imagination while maintaining material authorship. Empting was necessary to enable sufficient porosity where each medium allowed the other entry to its previously gated domain. The paintings are simple and subtle to allow the odd sonic textures a chance to work on the viewer’s engagement with them. The sound remains both abstract, using noise-like textures, and at a low volume to allow the audience’s attention to wander back and forth between aspects of the works.
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A growing body of evidence suggests that mitochondrial function may be important in brain development and psychiatric disorders. However, detailed expression profiles of those genes in human brain development and fear-related behavior remain unclear. Using microarray data available from the public domain and the Gene Ontology analysis, we identified the genes and the functional categories associated with chronological age in the prefrontal cortex (PFC) and the caudate nucleus (CN) of psychiatrically normal humans ranging in age from birth to 50 years. Among those, we found that a substantial number of genes in the PFC (115) and the CN (117) are associated with the GO term: mitochondrion (FDR qv <0.05). A greater number of the genes in the PFC (91%) than the genes in the CN (62%) showed a linear increase in expression during postnatal development. Using quantitative PCR, we validated the developmental expression pattern of four genes including monoamine oxidase B (MAOB), NADH dehydrogenase flavoprotein (NDUFV1), mitochondrial uncoupling protein 5 (SLC25A14) and tubulin beta-3 chain (TUBB3). In mice, overall developmental expression pattern of MAOB, SLC25A14 and TUBB3 in the PFC were comparable to the pattern observed in humans (p<0.05). However, mice selectively bred for high fear did not exhibit normal developmental changes of MAOB and TUBB3. These findings suggest that the genes associated with mitochondrial function in the PFC play a significant role in brain development and fear-related behavior.
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Background Radiation-induced skin reaction (RISR) is a common side effect that affects the majority of cancer patients receiving radiation treatment. RISR is often characterised by swelling,redness, pigmentation, fibrosis, and ulceration, pain, warmth, burning, and itching of the skin. The aim of this systematic review was to assess the effects of interventions which aim to prevent or manage RISR in people with cancer. Methods We searched the following databases up to November 2012: Cochrane Skin Group Specialised Register, CENTRAL (2012, Issue 11), MEDLINE (from 1946), EMBASE (from 1974), PsycINFO (from 1806), CINAHL (from 1981) and LILACS (from 1982). Randomized controlled trials evaluating interventions for preventing or managing RISR in cancer patients were included. The primary outcomes were development of RISR, and levels of RISR and symptom severity. Secondary outcomes were time taken to develop erythema or dry desquamation; quality of life; time taken to heal, a number of skin reaction and symptom severity measures; cost, participant satisfaction; ease of use and adverse effects. Where appropriate, we pooled results of randomized controlled trials using mean differences (MD) or odd ratios (OR) with 95% confidence intervals (CI). Results Forty-seven studies were included in this review. These evaluated six types of interventions (oral systemic medications; skin care practices; steroidal topical therapies; non-steroidal topical therapies; dressings and other). Findings from two meta-analyses demonstrated significant benefits of oral Wobe-Mugos E for preventing RISR (OR 0.13 (95% CI 0.05 to 0.38)) and limiting the maximal level of RISR (MD −0.92 (95% CI −1.36 to −0.48)). Another meta-analysis reported that wearing deodorant does not influence the development of RISR (OR 0.80 (95% CI 0.47 to 1.37)). Conclusions Despite the high number of trials in this area, there is limited good, comparative research that provides definitive results suggesting the effectiveness of any single intervention for reducing RISR. More research is required to demonstrate the usefulness of a wide range of products that are being used for reducing RISR. Future efforts for reducing RISR severity should focus on promising interventions, such as Wobe-Mugos E and oral zinc.
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The flexible design of decoupling and matching networks for coupled antennas is introduced. The network includes three parts: circuits for impedance transformation, an element for odd-mode decoupling and conventional matching networks. It is found that all three parts are determined by one parameter of the ABCD matrix of the impedance transformation circuit. Thus a large variety of circuits with different element values can be used for decoupling which relaxes the practical design constraints.
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The bed nucleus of the stria terminalis (BNST) is believed to be a critical relay between the central nucleus of the amygdala (CE) and the paraventricular nucleus of the hypothalamus in the control of hypothalamic–pituitary– adrenal (HPA) responses elicited by conditioned fear stimuli. If correct, lesions of CE or BNST should block expression of HPA responses elicited by either a specific conditioned fear cue or a conditioned context. To test this, rats were subjected to cued (tone) or contextual classical fear conditioning. Two days later, electrolytic or sham lesions were placed in CE or BNST. After 5 days, the rats were tested for both behavioral (freezing) and neuroendocrine (corticosterone) responses to tone or contextual cues. CE lesions attenuated conditioned freezing and corticosterone responses to both tone and con- text. In contrast, BNST lesions attenuated these responses to contextual but not tone stimuli. These results suggest CE is indeed an essential output of the amygdala for the expres- sion of conditioned fear responses, including HPA re- sponses, regardless of the nature of the conditioned stimu- lus. However, because lesions of BNST only affected behav- ioral and endocrine responses to contextual stimuli, the results do not support the notion that BNST is critical for HPA responses elicited by conditioned fear stimuli in general. Instead, the BNST may be essential specifically for contex- tual conditioned fear responses, including both behavioral and HPA responses, by virtue of its connections with the hippocampus, a structure essential to contextual condition- ing. The results are also not consistent with the hypothesis that BNST is only involved in unconditioned aspects of fear and anxiety.
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Chronic ethanol exposure leads to dysregulation of the hypothalamic-pituitary-adrenal axis, leading to changes in glucocorticoid release and function that have been proposed to maintain pathological alcohol consumption and increase vulnerability to relapse during abstinence. The objective of this study was to determine whether mifepristone, a glucocorticoid receptor antagonist, plays a role in ethanol self-administration and reinstatement. Male, Long-Evans rats were trained to self-administer either ethanol or sucrose in daily 30 min operant self-administration sessions using a fixed ratio 3 schedule of reinforcement. Following establishment of stable baseline responding, we examined the effects of mifepristone on maintained responding and yohimbine-induced increases in responding for ethanol and sucrose. Lever responding was extinguished in separate groups of rats and animals were tested for yohimbine-induced reinstatement and corticosterone release. We also investigated the effects of local mifepristone infusions into the central amygdala (CeA) on yohimbine-induced reinstatement of ethanol- and sucrose-seeking. In addition, we infused mifepristone into the basolateral amygdala (BLA) in ethanol-seeking animals as an anatomical control. We show that both systemic and intra-CeA (but not BLA) mifepristone administration suppressed yohimbine-induced reinstatement of ethanol-seeking, while only systemic injections attenuated sucrose-seeking. In contrast, baseline consumption, yohimbine-induced increases in responding, and circulating CORT levels were unaffected. The data indicate that the CeA plays an important role in the effects of mifepristone on yohimbine-induced reinstatement of ethanol-seeking. Mifepristone may be a valuable pharmacotherapeutic strategy for preventing relapse to alcohol use disorders and, as it is FDA approved, may be a candidate for clinical trials in the near future.
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INTRODUCTION CASES For a number of years, Professor Myles McGregor-Lowndes, Frances Hannah and Anne Overell have compiled one to two page summaries of cases involving nonprofit organisations and published them on The Australian Centre for Philanthropy and Nonprofit Studies, Developing Your Organisation (DYO) website.1 You can be alerted of new case summaries as they are posted to the DYO website by subscribing to the ACPNS RSS feed or the ACPNS twitter service.2 There were some very significant cases during 2013, such as Commissioner of Taxation v Cancer & Bowel Research Association (see case notes 2.8.2 and 2.8.11), The Hunger Project case which is under appeal, but could change the face of PBI jurisprudence (see case note 2.8.7) while Home Health Pty Ltd retained the PBI status quo but might have been different if appealed (see case note 2.8.8). For sheer interest there is nothing better in my 30 odd years of reading tax and charity judgements than case involving The Study and Prevention of Psychological Diseases Foundation Incorporated (see case note 2.1.1). It even rivals some of the more bizarre cases from the US jurisdiction of which St Joseph Abbey v Castille (case note 2.10.9) is certainly ‘dead centre’. A set of cases which stand out for attention are those involving New Zealand’s Christchurch Cathedral which anyone with responsibility for heritage-listed buildings should study carefully, for implications in relation to their own circumstances. A number of cases summarised in this Almanac are working their way through the appeals process and care should be taken with their application. In addition, some of the cases are from jurisdictions outside Australia, and readers should exercise caution when considering the implications of these cases for Australian law. LEGISLATION The Almanac includes a review of major statutory amendments during 2013, which are relevant to the nonprofit sector in all Australian jurisdictions. Special thanks must go to Nathan MacDonald and the JusticeConnect team for providing legislative updates for Victoria. SPECIAL ISSUES DURING 2013 A number of legal practitioners have contributed articles on significant legal issues facing nonprofit organisations: charitable trusts giving to government entities (Alice Macdougall); workplace bullying (Tim Longwill); and privacy (James Tan and Nina Brewer). WORLD ROUND-UP Major developments from the UK and Ireland (Kerry O’Halloran), Canada (Peter Broder), New Zealand (Michael Gousmett and Susan Barker) and Jamaica (Frances Hannah) are all summarised in a review of a significant part of the common law charity jurisdictions. WHAT DOES 2014 HOLD The final section moves from looking in the rear view mirror to peering out the front windscreen to discern the reform agenda. The view from the windscreen in 2013 was of considerable reform traffic at the Commonwealth level jostling for a place in the parliamentary agenda. This year is quite different with a smaller number of vehicles ahead, but the potential for significant impact.
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Potenital pathways for the deactivation of hindered amine light stabilisers (HALS) have been investigated by observing reactions of model compounds-based on 4-substituted derivatives of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO)-with hydroxyl radicals. In these reactions, dilute aqueous suspensions of photocatalytic nanoparticulate titanium dioxide were irradiated with UV light in the presence of water-soluble TEMPO derivatives. Electron spin resonance (ESR) and electrospray ionisation mass-spectrometry (ESI-MS) data were acquired to provide complementary structural elucidation of the odd-and even-electron products of these reactions and both techniques show evidence for the formation of 4-oxo-TEMPO (TEMPONE). TEMPONE formation from the 4-substituted TEMPO compounds is proposed to be initiated by hydrogen abstraction at the 4-position by hydroxyl radical. High-level ab initio calculations reveal a thermodynamic preference for abstraction of this hydrogen but computed activation barriers indicate that, although viable, it is less favoured than hydrogen abstraction from elsewhere on the TEMPO scaffold. If a radical is formed at the 4-position however, calculations elucidate two reaction pathways leading to TEMPONE following combination with either a second hydroxyl radical or dioxygen. An alternate mechanism for conversion of TEMPOL to TEMPONE via an alkoxyl radical intermediate is also considered and found to be competitive with the other pathways. ESI-MS analysis also shows an increased abundance of analogous 4-substituted piperidines during the course of irradiation, suggesting competitive modification at the 1-position to produce a secondary amine. This modification is confirmed by characteristic fragmentation patterns of the ionised piperidines obtained by tandem mass spectrometry. The conclusions describe how reaction at the 4-position could be responsible for the gradual depletion of HALS in pigmented surface coatings and secondly, that modification at nitrogen to form the corresponding secondary amine species may play a greater role in the stabilisation mechanisms of HALS than previously considered.
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The rat nucleus accumbens contains medium-sized, spiny projection neurons and intrinsic, local circuit neurons, or interneurons. Sub-classes of interneurons, revealed by calretinin (CR) or parvalbumin (PV) immunoreactivity or reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry, were compared in the nucleus accumbens core, shell and rostral pole. CR, PV and NADPH-diaphorase-containing neurons are shown to form three non-co-localising populations in these three areas. No significant differences in neuronal population densities were found between the subterritories. NADPH-diaphorase-containing neurons could be further separated morphologically into three sub-groups, but CR- and PV-immunoreactive neurons form homogeneous populations. Ultrastructurally, NADPH-diaphorase-, CR- and PV-containing neurons in the nucleus accumbens all possess nuclear indentations. These are deeper and fewer in neurons immunoreactive for PV than in CR- and NADPH-diaphorase-containing neurons. CR-immunoreactive boutons form asymmetrical and symmetrical synaptic specialisations on spines, dendrites and somata, while PV-immunoreactive boutons make only symmetrical synaptic specialisations. Both CR- and PV-immunoreactive boutons form symmetrical synaptic specialisations with medium-sized spiny neurons and contact other CR- and PV-immunoreactive somata, respectively. A novel non-carcinogenic substrate for the peroxidase reaction (Vector Slate Grey, SG) was found to be characteristically electron-dense and may be distinguishable from the diaminobenzidine reaction product. We conclude that the three markers used in this study are localised in distinct populations of nucleus accumbens interneurons. Our studies of their synaptic connections contribute to an increased understanding of the intrinsic circuitry of this area.
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Both tyrosine hydroxylase-positive fibres from the mesolimbic dopamine system and amygdala projection fibres from the basolateral nucleus are known to terminate heavily in the nucleus accumbens. Caudal amygdala fibres travelling dorsally via the stria terminalis project densely to the nucleus accumbens shell, especially in the dopamine rich septal hook. The amygdala has been associated with the recognition of emotionally relevant stimuli while the mesolimbic dopamine system is implicated with reward mechanisms. There is behavioural and electrophysiological evidence that the amygdala input to the nucleus accumbens is modulated by the mesolimbic dopamine input, but it is not known how these pathways interact anatomically within the nucleus accumbens. Using a variety of neuroanatomical techniques including anterograde and retrograde tracing, immunocytochemistry and intracellular filling, we have demonstrated convergence of these inputs on to medium-sized spiny neurons. The terminals of the basolateral amygdala projection make asymmetrical synapses predominantly on the heads of spines which also receive on their necks or adjacent dendrites, symmetrical synaptic input from the mesolimbic dopamine system. Some of these neurons have also been identified as projection neurons, possibly to the ventral pallidum. We have shown a synaptic level how dopamine is positioned to modulate excitatory limbic input in the nucleus accumbens.
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We introduce a new mechanism for the propulsion and separation by chirality of small ferromagnetic particles suspended in a liquid. Under the action of a uniform dc magnetic field H and an ac electric field E isomers with opposite chirality move in opposite directions. Such a mechanism could have a significant impact on a wide range of emerging technologies. The component of the chiral velocity that is odd in H is found to be proportional to the intrinsic orbital and spin angular momentum of the magnetized electrons. This effect arises because a ferromagnetic particle responds to the applied torque as a small gyroscope. © 2012 American Physical Society.