673 research outputs found
Near-Infrared Coronagraphic Observations of the T Tauri Binary System UY Aur
We present a near-infrared image of UY Aur, a 0.9" separated binary system,
using the Coronagraphic Imager with Adaptive Optics on the Subaru Telescope.
Thanks to adaptive optics, the spatial resolution of our image was ~0.1" in the
full width at half maximum of the point spread function, the highest achieved.
By comparison with previous measurements, we estimated that the orbital period
is ~1640 yrs and the total mass of the binary is ~1.73 solar mass. The observed
H-band magnitude of the secondary varies by as much as 1.3 mag within a decade,
while that of the primary is rather stable. This inconstancy may arise from
photospheric variability caused by an uneven accretion rate or from the
rotation of the secondary. We detected a half-ring shaped circumbinary disk
around the binary with a bright southwest part but a barely detectable
northeast portion. The brightness ratio is ~57. Its inner radius and
inclination are about 520 AU and 42, respectively. The disk is not uniform but
has remarkable features, including a clumpy structure along the disk,
circumstellar material inside the inner cavity, and an extended armlike
structure. The circumstellar material inside the cavity probably corresponds to
a clump or material accreting from the disk onto the binary. The armlike
structure is a part of the disk, created by the accretion from the outer region
of the disk or encounters with other stellar systems.Comment: 16 pages, 6 figures; accepted for publication in A
Intellectual functioning in pediatric patients with epilepsy: a comparison of medically controlled, medically uncontrolled and surgically controlled children
OBJETIVO: Comparar o quociente intelectual (QI) em três grupos de crianças com epilepsia: 1) controlados com medicação, 2) não controlados com medicação e 3) controlados com cirurgia. MÉTODOS: Noventa e oito pacientes pediátricos, com idades entre 6 e 12 anos, foram selecionados de dezembro de 2007 a julho de 2008. A Escala de Inteligência Wechsler para Crianças - terceira edição (WISC-III) foi utilizada para a avaliação neuropsicológica dos pacientes. Os resultados foram relacionados com a síndrome epiléptica, a etiologia da epilepsia, o tratamento medicamentoso, a idade do paciente no início da epilepsia e a duração da epilepsia. RESULTADOS: Os escores da WISC foram significativamente melhores no grupo controlado com medicação quando comparados aos do grupo não controlado com medicação. O grupo controlado com medicação obteve um desempenho significativamente melhor na maioria dos subtestes da WISC quando comparado ao grupo não controlado com medicação: vocabulário, aritmética, compreensão, memória de dígitos, completar figuras, arranjo de figuras e cubos. Um número significativamente maior de pacientes com epilepsia idiopática e uso de monoterapia foi observado no grupo controlado com medicação quando comparado ao grupo não controlado. O grupo controlado com cirurgia não apresentou diferença significativa no desempenho do QI quando comparado ao grupo controlado com medicação. CONCLUSÕES: As crianças com um bom controle de crises tiveram um melhor desempenho no QI geral, verbal e de execução quando comparadas às crianças com epilepsia refratária. Esses resultados podem ser influenciados por fatores clínicos como o uso de monoterapia, o tipo de droga antiepiléptica utilizada, a síndrome epiléptica e a etiologia da epilepsia. A cirurgia de epilepsia pode causar um impacto positivo no desempenho cognitivo das crianças que ficaram livres de crises após o procedimento cirúrgico.OBJECTIVE: To compare the intellectual coefficient (IQ) of three groups of children with epilepsy: 1) medically controlled, 2) medically uncontrolled and 3) surgically controlled. METHODS: From December 2007 until July 2008, 98 pediatric patients were selected, with an age range between 6 and 12 years. Neuropsychological assessment included the Wechsler Intelligence Scale for Children - third edition (WISC-III). Results are related to epileptic syndrome, etiology of epilepsy, drug therapy, age at epilepsy onset and epilepsy duration. RESULTS: WISC scores were significantly better in the medically controlled group when compared to the medically uncontrolled group. The medically controlled group performed significantly better in the majority of the WISC subtests when compared to the medically uncontrolled group: vocabulary, arithmetic, comprehension, digit span, picture completion, picture arrangement, and block design. A significantly higher number of idiopathic epilepsy and monotherapy cases was observed in the medically controlled group when compared to the medically uncontrolled group. Surgically controlled children had no significant differences in IQ performance when compared to medically controlled children. CONCLUSIONS: Children with good seizure control have higher general, verbal and performed intelligence when compared to children with refractory epilepsy. These results may be influenced by clinical factors such as use of monotherapy, drug type and epileptic syndrome and etiology. Epilepsy surgery can have a positive impact on cognitive performance of children who were free of seizures after surgery
Lattice congruences of the weak order
We study the congruence lattice of the poset of regions of a hyperplane
arrangement, with particular emphasis on the weak order on a finite Coxeter
group. Our starting point is a theorem from a previous paper which gives a
geometric description of the poset of join-irreducibles of the congruence
lattice of the poset of regions in terms of certain polyhedral decompositions
of the hyperplanes. For a finite Coxeter system (W,S) and a subset K of S, let
\eta_K:w \mapsto w_K be the projection onto the parabolic subgroup W_K. We show
that the fibers of \eta_K constitute the smallest lattice congruence with
1\equiv s for every s\in(S-K). We give an algorithm for determining the
congruence lattice of the weak order for any finite Coxeter group and for a
finite Coxeter group of type A or B we define a directed graph on subsets or
signed subsets such that the transitive closure of the directed graph is the
poset of join-irreducibles of the congruence lattice of the weak order.Comment: 26 pages, 4 figure
The G2019S LRRK2 Mutation is Rare in Korean Patients with Parkinson's Disease and Multiple System Atrophy
Background and Purpose The LRRK2 (PARK8; OMIM607060)substitution was recently identified as a causative mutation for Parkinson`s disease (PD). The pathologic heterogeneity of LRRK2-positive patients Suggests that mutation of the LRRK2 gene is associated with the pathogenesis of PD and Parkinson-plus disorders, such as multiple system atrophy (MSA). We previously reported that the G2019S LRRK2 mutation-which is the most common LRRK-2 mutation-was not found in a sample of 453 Korean PD patients. In the present study, we extended the screening for the G2019S Mutation to a larger group of PD and MSA patients. Methods We performed a genetic analysis of the G2019S mutation ill 877 patients with PD and 199 patients with MSA using a standard PCR and restriction digestion method. Results None of the subjects carried the G2019S mutation. Conclusions The results of the present study support that the G2019S Mutation is extremely rare in PD and is unlikely to be associated with MSA in the Korean population. J Clin Neurol 2009;5:29-32This study was in part supported by a grant of the Korea Health 21 R &
D Project. Ministry of Health & Welfare, Republic of Korea (03-PJ10-
PG13-GD01-0002).Lin CH, 2008, J BIOMED SCI, V15, P661, DOI 10.1007/s11373-008-9260-0Healy DG, 2008, LANCET NEUROL, V7, P583, DOI 10.1016/S1474-4422(08)70117-0CHO JW, 2008, J CLIN NEUROL, V4, P23Ozelius LJ, 2007, MOVEMENT DISORD, V22, P546, DOI 10.1002/mds.21343Cho JW, 2007, CAN J NEUROL SCI, V34, P53Punia S, 2006, NEUROSCI LETT, V409, P83, DOI 10.1016/j.neulet.2006.04.052Hardy J, 2006, ANN NEUROL, V60, P389, DOI 10.1002/ana.21022Zabetian CP, 2006, NEUROLOGY, V67, P697Tomiyama H, 2006, MOVEMENT DISORD, V21, P1102, DOI 10.1002/mds.20886Tan EK, 2006, MOVEMENT DISORD, V21, P997, DOI 10.1002/mds.20875Fung HC, 2006, MOVEMENT DISORD, V21, P880, DOI 10.1002/mds.20814Schapira AHV, 2006, NEUROLOGY, V66, pS10Infante J, 2006, NEUROSCI LETT, V395, P224, DOI 10.1016/j.neulet.2005.10.083Giasson BI, 2006, ANN NEUROL, V59, P315, DOI 10.1002/ana.20791Taylor JP, 2006, TRENDS MOL MED, V12, P76, DOI 10.1016/j.molmed.2005.12.004Ross OA, 2006, ANN NEUROL, V59, P388, DOI 10.1002/ana.20731Lesage S, 2006, NEW ENGL J MED, V354, P422Ozelius LJ, 2006, NEW ENGL J MED, V354, P424Goldwurm S, 2006, PARKINSONISM RELAT D, V12, P410, DOI 10.1016/j.parkreldis.2006.04.001Hernandez D, 2005, NEUROSCI LETT, V389, P137, DOI 10.1016/j.neulet.2005.07.044Farrer M, 2005, NEUROLOGY, V65, P738Tan EK, 2005, NEUROSCI LETT, V384, P327, DOI 10.1016/j.neulet.2005.04.103Gasser T, 2005, CURR OPIN NEUROL, V18, P363Funayama M, 2005, ANN NEUROL, V57, P918, DOI 10.1002/ana.20484Kachergus J, 2005, AM J HUM GENET, V76, P672Gilks WP, 2005, LANCET, V365, P415Lu CS, 2005, PARKINSONISM RELAT D, V11, P521, DOI 10.1016/j.parkreldis.2005.09.003Nichols WC, 2005, LANCET, V365, P410Paisan-Ruiz C, 2004, NEURON, V44, P595Zimprich A, 2004, NEURON, V44, P601Wszolek ZK, 2004, NEUROLOGY, V62, P1619Funayama M, 2002, ANN NEUROL, V51, P296, DOI 10.1002/ana.10113Autere JM, 2000, J NEUROL NEUROSUR PS, V69, P107Gilman S, 1999, J NEUROL SCI, V163, P94HUGHES AJ, 1992, J NEUROL NEUROSUR PS, V55, P181
Cerebral palsy aetiologic diagnosis
A retrospective study was carried on 35 cases with Cerebral Palsy, obtained at random, attended at the Hospital of Clinics of School Medicine of São Paulo University, Campus Ribeirão Preto, from 1982 to 1998, with the scope to verify the aetiologic factors. Among 25 patients with identified aetiology, the Congenital infections (36%) and hypoxic-schemic cerebral lesions (28%) were the major causes. These results could be used for regional strategies of deficiencies prevention. Comments about the cases without aetiology identified points to the need to consider the inherited cerebral palsies and the differential diagnosis with degenerative diseases.Em estudo retrospectivo foram analisados 35 prontuários, obtidos ao acaso, de crianças com diagnóstico de Paralisia Cerebral (PC), atendidas no Hospital das Clínicas de Ribeirão Preto, entre 1982 e 1998, com o objetivo de verificar fatores etiológicos. As infecções congênitas (36%) e agressão hipóxico-isquêmica (28%) foram os mais freqüentes fatores determinantes de PC entre 25 casos com etiologia definida. Estes achados podem ser utilizados para estratégias regionais de prevenção de deficiências. Para os casos sem etiologia definida, lembram-se as formas herdadas de paralisia cerebral e o diagnóstico diferencial com doenças degenerativas
The Rewiring of Ubiquitination Targets in a Pathogenic Yeast Promotes Metabolic Flexibility, Host Colonization and Virulence
Funding: This work was funded by the European Research Council [http://erc.europa.eu/], AJPB (STRIFE Advanced Grant; C-2009-AdG-249793). The work was also supported by: the Wellcome Trust [www.wellcome.ac.uk], AJPB (080088, 097377); the UK Biotechnology and Biological Research Council [www.bbsrc.ac.uk], AJPB (BB/F00513X/1, BB/K017365/1); the CNPq-Brazil [http://cnpq.br], GMA (Science without Borders fellowship 202976/2014-9); and the National Centre for the Replacement, Refinement and Reduction of Animals in Research [www.nc3rs.org.uk], DMM (NC/K000306/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Acknowledgments We thank Dr. Elizabeth Johnson (Mycology Reference Laboratory, Bristol) for providing strains, and the Aberdeen Proteomics facility for the biotyping of S. cerevisiae clinical isolates, and to Euroscarf for providing S. cerevisiae strains and plasmids. We are grateful to our Microscopy Facility in the Institute of Medical Sciences for their expert help with the electron microscopy, and to our friends in the Aberdeen Fungal Group for insightful discussions.Peer reviewedPublisher PD
Control of human endometrial stromal cell motility by PDGF-BB, HB-EGF and trophoblast-secreted factors
Human implantation involves extensive tissue remodeling at the fetal-maternal interface. It is becoming increasingly evident that not only trophoblast, but also decidualizing endometrial stromal cells are inherently motile and invasive, and likely contribute to the highly dynamic processes at the implantation site. The present study was undertaken to further characterize the mechanisms involved in the regulation of endometrial stromal cell motility and to identify trophoblast-derived factors that modulate migration. Among local growth factors known to be present at the time of implantation, heparin-binding epidermal growth factor-like growth factor (HB-EGF) triggered chemotaxis (directed locomotion), whereas platelet-derived growth factor (PDGF)-BB elicited both chemotaxis and chemokinesis (non-directed locomotion) of endometrial stromal cells. Supernatants of the trophoblast cell line AC-1M88 and of first trimester villous explant cultures stimulated chemotaxis but not chemokinesis. Proteome profiling for cytokines and angiogenesis factors revealed neither PDGF-BB nor HB-EGF in conditioned media from trophoblast cells or villous explants, while placental growth factor, vascular endothelial growth factor and PDGF-AA were identified as prominent secretory products. Among these, only PDGF-AA triggered endometrial stromal cell chemotaxis. Neutralization of PDGF-AA in trophoblast conditioned media, however, did not diminish chemoattractant activity, suggesting the presence of additional trophoblast-derived chemotactic factors. Pathway inhibitor studies revealed ERK1/2, PI3 kinase/Akt and p38 signaling as relevant for chemotactic motility, whereas chemokinesis depended primarily on PI3 kinase/Akt activation. Both chemotaxis and chemokinesis were stimulated upon inhibition of Rho-associated, coiled-coil containing protein kinase. The chemotactic response to trophoblast secretions was not blunted by inhibition of isolated signaling cascades, indicating activation of overlapping pathways in trophoblast-endometrial communication. In conclusion, trophoblast signals attract endometrial stromal cells, while PDGF-BB and HB-EGF, although not identified as trophoblast-derived, are local growth factors that may serve to fine-tune directed and non-directed migration at the implantation site
Wnt signaling in breast cancer: have we come full circle?
Since the original identification of Wnt1 as a mammary oncogene in mouse mammary tumor virus infected mice, questions have been asked about its relevance to human breast cancer. Wnt1 is now known to be one of a large family of Wnt genes encoding structurally similar secreted signaling proteins, several of which are functionally redundant. The principal intracellular signaling pathway activated by these proteins has been elucidated in recent years. Components of this pathway include proto-oncogene products, such as β-catenin, and tumor suppressor proteins such as APC. Although WNT1 itself has not been implicated in human breast neoplasms, it has been reported that other WNT genes are sometimes overexpressed in human breast cancer and there is growing evidence that downstream components of the Wnt signaling pathway are activated in a significant proportion of breast tumors
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