To determine whether reduced striatal D2 receptor binding reported in patients with idiopathic torsion dystonia is associated with the genotype, the authors used PET and 11C-raclopride to assess ...non-manifesting carriers of the DYT1 mutation. D2 receptor binding was reduced by approximately 15% in caudate and putamen (p < 0.005). These results suggest that striatal D2 binding reductions are a trait feature of the DYT1 genotype.
Swertia chirayita- an overview Joshi, P., TERI School of Advanced Studies (India));Dhawan, V.(Energy and Resourses Institute, Lodhi Road (India)
Current science (Bangalore),
08/2005, Letnik:
89, Številka:
4
Journal Article
Recenzirano
Swcrtia chirayita is a medicinal plant indigenous to temperate Himalaya. Its medicinal usage is reported in Indian pharmaceutical codex, the British and the American pharmacopoeias and in different ...traditional systems of medicines such as the Ayurveda, Unani andSiddha. The plant is used as a bitter tonic in treatment of fever and for curing various skin diseases. S. chirayita has an established domestic (Indian) and international market, which is increasing at a rate of 10 annually. The plant available in the market many a times is adulterated and substituted by close relatives of chirata. This article briefly reviews the botany, pharmacology, biochemistry, market demand and trade of the plant. This is an attempt to compile and document information on different aspects of 5. chirayita and highlight the need for research and development.#
The 2009 November outburst of the neutron star X-ray binary Aquila X-1 (Aql X-1) was observed with unprecedented radio coverage and simultaneous pointed X-ray observations, tracing the radio emission ...around the full X-ray hysteresis loop of the outburst for the first time. We use these data to discuss the disk-jet coupling, finding the radio emission to be consistent with being triggered at state transitions, both from the hard to the soft spectral state and vice versa. Our data appear to confirm previous suggestions of radio quenching in the soft state above a threshold X-ray luminosity of {approx}10% of the Eddington luminosity. We also present the first detections of Aql X-1 with very long baseline interferometry, showing that any extended emission is relatively diffuse and consistent with steady jets rather than arising from discrete, compact knots. In all cases where multi-frequency data were available, the source radio spectrum is consistent with being flat or slightly inverted, suggesting that the internal shock mechanism that is believed to produce optically thin transient radio ejecta in black hole X-ray binaries is not active in Aql X-1.
A weak compact jet in a soft state of Cygnus X-1 Rushton, A; Miller-Jones, J. C. A; Campana, R ...
Monthly notices of the Royal Astronomical Society,
February 2012, Letnik:
419, Številka:
4
Journal Article
Recenzirano
Odprti dostop
We present evidence for the presence of a weak compact jet during a soft X-ray state of Cygnus X-1. Very-high-resolution radio observations were taken with the VLBA, EVN and MERLIN during a ...hard-to-soft spectral state change, showing the hard state jet to be suppressed by a factor of about 3-5 in radio flux and unresolved to direct imaging observations (i.e. ≲1 mas at 4 cm). High time-resolution X-ray observations with the RXTE-PCA were also taken during the radio monitoring period, showing the source to make the transition from the hard state to a softer state (via an intermediate state), although the source may never have reached the canonical soft state. Using astrometric very long baseline interferometry (VLBI) analysis and removing proper motion, parallax and orbital motion signatures, the residual positions show a scatter of ∼0.2 mas (at 4 cm) and ∼3 mas (at 13 cm) along the position angle of the known jet axis; these residuals suggest that there is a weak unresolved outflow, with varying size or opacity, during intermediate and soft X-ray states. Furthermore, no evidence was found for extended knots or shocks forming within the jet during the state transition, suggesting that the change in outflow rate may not be sufficiently high to produce superluminal knots.
Using new and archival radio data, we have measured the proper motion of the black hole X-ray binary V404 Cyg to be 9.2 ± 0.3 mas yr−1. Combined with the systemic radial velocity from the literature, ...we derive the full three-dimensional heliocentric space velocity of the system, which we use to calculate a peculiar velocity in the range 47–102 km s−1, with a best-fitting value of 64 km s−1. We consider possible explanations for the observed peculiar velocity and find that the black hole cannot have formed via direct collapse. A natal supernova is required, in which either significant mass (∼11 M⊙) was lost, giving rise to a symmetric Blaauw kick of up to ∼65 km s−1, or, more probably, asymmetries in the supernova led to an additional kick out of the orbital plane of the binary system. In the case of a purely symmetric kick, the black hole must have been formed with a mass ∼9 M⊙, since when it has accreted 0.5–1.5 M⊙ from its companion.
The space velocity of a stellar black hole encodes the history of its formation and evolution. Here we measure the three-dimensional motion of the microquasar GRS 1915+105, using a decade of ...astrometry with the NRAO Very Long Baseline Array, together with the published radial velocity. The velocity in the Galactic plane deviates from circular rotation by 53-80 plus or minus 8 km s super(-1), where the range covers any specific distance from 6-12 kpc. Perpendicular to the plane, the velocity is only 10 plus or minus 4 km s super(-1). The peculiar velocity is minimized at a distance 9-10 kpc and is then nearly In the radial direction toward the Galactic center. We discuss mechanisms for the origin of the peculiar velocity, and conclude that it is most likely a consequence of Galactic velocity diffusion on this old binary, rather than the result of a supernova kick during the formation of the 14 M unk black hole. Finally, a brief comparison is made with four other black hole (BH) binaries whose kinematics are well determined.
Background: Patients presenting with asymmetrical postural tremor with or without mild rest tremor may be diagnosed as having essential tremor (ET), although there is considerable diagnostic ...uncertainty as to the long term outcome of these patients. Objective: In this study, retrospective observations were made on 13 patients presenting originally with asymmetrical postural tremor, initially thought to have ET based on tremor characteristics, alcohol responsiveness, and family history but who subsequently met the criteria of Parkinson’s disease (PD). Methods: The patients were observed and followed up clinically with ancillary imaging using dopamine transporter SPECT scan or levodopa challenge tests in some cases. The diagnosis at original presentation with postural tremor was made with retrospective case note review. Results: After a variable and long latent period all patients developed additional signs suggesting a clinical diagnosis of PD although picking up an initial label of ET. Conclusions: We suggest exercising caution regarding a diagnosis of ET in patients presenting with late onset asymmetrical postural tremor even if there is no rest tremor. Alcohol sensitivity of tremor, family history of tremor, or responsiveness to β blockers may not be helpful in diagnosing ET in these cases and some may develop PD in the long term.
True-to-type clonal fidelity is of paramount concern during micropropagation of crop species. Though, micropropagation has found an important role in propagation of apple rootstocks, commercial ...propagation may be constrained by the occurrence of genetic variations, especially when cultures are maintained in vitro for a long period. To determine genetic fidelity of micropropagated plants of apple rootstock MM 106 multiplied by enhanced axillary branching method, we screened 24 inter simple sequence repeat markers (ISSR). Of these, 11 primers reproducibly generated a total of 107 distinct bands. Apple rootstock Merton 793 and scion ‘Jonathon’ were analysed along with tissue culture raised progenies of MM 106 as outliers to rule out the possibility that the invariant banding pattern was on account of inefficiency of ISSR primers in detecting variations. The number of bands per primer varied from 5 to 9 with an average of 9.72 scorable bands per primer. Among 83 bands amplified in micropropagated plants of MM 106, 78 bands were monomorphic (93.9%) and 5 bands (6.02%) were polymorphic. The results showed that ISSR markers can be used to gain rapid and precise information about the genetic stability of micropropagated apple rootstock MM 106 and corroborated the fact that the cultures multiplied through pre-existing meristems (axillary branching) may also show genetic instability especially upon extended in vitro cultivation.
To assess the effects of levodopa on resting-state brain metabolism in PD.
In previous studies the authors used 18F fluorodeoxyglucose (FDG) and PET to quantify regional metabolic abnormalities in ...PD. They found that this disease is characterized reproducibly by a specific abnormal PD-related pattern (PDRP). In this study the authors used IV levodopa infusion to quantify the effects of dopamine replacement on regional metabolism and PDRP network activity. They tested the hypothesis that clinical response to dopaminergic therapy correlates with these metabolic changes.
The authors used FDG/PET to measure resting-state regional brain metabolism in seven patients with PD (age, 59.4 +/- 4.2 years; Hoehn and Yahr stage, 1.9 +/- 0.7, mean +/- SD); subjects were scanned both off levodopa and during an individually titrated constant-rate IV levodopa infusion. The authors used statistical parametric mapping to identify significant changes in regional brain metabolism that occurred with this intervention. They also quantified levodopa-induced changes in PDRP expression. Metabolic changes with levodopa correlated with clinical improvement as measured by changes in Unified PD Rating Scale (UPDRS) motor scores.
Levodopa infusion improved UPDRS motor ratings (30.6% +/- 12.0%, p < 0.002) and significantly decreased regional glucose metabolism in the left putamen, right thalamus, bilateral cerebellum, and left primary motor cortex (p < 0.001). Changes in pallidal metabolism correlated significantly with clinical improvement in UPDRS motor ratings (p < 0.01). Levodopa infusion also resulted in a significant (p = 0.01) decline in PDRP expression. The changes in PDRP activity mediated by levodopa correlated significantly with clinical improvement in UPDRS motor ratings (r = -0.78, p < 0.04).
Levodopa reduces brain metabolism in the putamen, thalamus, and cerebellum in patients with PD. Additionally, levodopa reduces PD-related pattern activity, and the degree of network suppression correlates with clinical improvement. The response to dopaminergic therapy in Patients with PD may be determined by the modulation of cortico-striato-pallido-thalamocortical pathways.
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