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1.
Phys Rev Lett ; 119(1): 014801, 2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28731757

RESUMEN

This Letter reports the successful use of feedback from a spin polarization measurement to the revolution frequency of a 0.97 GeV/c bunched and polarized deuteron beam in the Cooler Synchrotron (COSY) storage ring in order to control both the precession rate (≈121 kHz) and the phase of the horizontal polarization component. Real time synchronization with a radio frequency (rf) solenoid made possible the rotation of the polarization out of the horizontal plane, yielding a demonstration of the feedback method to manipulate the polarization. In particular, the rotation rate shows a sinusoidal function of the horizontal polarization phase (relative to the rf solenoid), which was controlled to within a 1 standard deviation range of σ=0.21 rad. The minimum possible adjustment was 3.7 mHz out of a revolution frequency of 753 kHz, which changes the precession rate by 26 mrad/s. Such a capability meets a requirement for the use of storage rings to look for an intrinsic electric dipole moment of charged particles.

2.
Phys Rev Lett ; 115(11): 113007, 2015 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-26406831

RESUMEN

The preservation of the nuclear polarization of hydrogen atoms during the recombination to molecules was observed on different surface materials in the temperature range from 45 to 100 K and for magnetic fields up to 1 T. On a gold and a fused quartz surface, the expected molecular polarization of about 50% or lower of the atomic polarization was measured, while a surface layer of perfluoropolyether (Fomblin) shows a nearly complete preservation (at least 97%) of the atomic polarization during the recombination process. Further experiments have the possibility of storing polarized deuterium molecules and to use them in nuclear-fusion installations. Another application might be the production of polarized substances for enhanced NMR techniques.

3.
Biol Sport ; 32(2): 169-73, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26060342

RESUMEN

Increasing numbers of dietary supplements with ecdysteroids are marketed as "natural anabolic agents". Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 µM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 µM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERß mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class "S1.2 Other Anabolic Agents" of the list of prohibited substances of the World Anti-Doping Agency.

4.
Pharmacopsychiatry ; 42(3): 101-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19452378

RESUMEN

AIM: Aripiprazole (ABILIFY) is an effective antipsychotic used in a dose range from 10 to 30 mg, administered once daily. Soon after its approval in Germany for treatment of schizophrenia, a 12-month post-marketing surveillance study was initiated that included 1 096 patients cared for by 408 office-based psychiatrists and/or neurologists in private practice. The aim was to gain further insights into safety and efficacy of aripiprazole in an outpatient real-life setting focusing on general health, well-being and psychosocial functioning. PATIENTS AND METHODS: Efficacy was rated by using standard CGI, SF-12 and SIWM-PsySo instruments for severity of disease, physical and mental health outcomes and psychosocial state, respectively. Safety was evaluated according to the reports of adverse events. Mean total daily dose of aripiprazole increased from 15.4 mg at the visit after 1 month to 17.6 mg at the visits after 6 to 12 months, the most frequently administered maintenance dose being 15 mg. RESULTS AND DISCUSSION: Within the observation period significant improvements of CGI, SF-12 and SIWM-PsySo scores over time versus baseline values were observed (p<0.001) when starting with or switching to aripiprazole. Physicians observed improvements in 80.7% of the patients at endpoint; in 62% of the patients the disease state was considered "much" or "very much" improved. Aripiprazole was overall well tolerated; 19.9% of patients discontinued treatment after 12 months. Adverse effects in general were moderate to mild and corresponded to the known tolerability profile of aripiprazole. Psychotic side effects reported were probably due to a recurrence of the underlying schizophrenic disorder. CONCLUSION: The results indicate that aripiprazole may be an efficacious and safe treatment option for pre-treated patients with schizophrenia also in a naturalistic psychiatrist/neurologist practice setting with effects on health and psychosocial functioning and a comparably low dropout rate.


Asunto(s)
Antipsicóticos/administración & dosificación , Indicadores de Salud , Piperazinas/administración & dosificación , Vigilancia de Productos Comercializados , Quinolonas/administración & dosificación , Esquizofrenia/tratamiento farmacológico , Antipsicóticos/efectos adversos , Aripiprazol , Alemania , Humanos , Consultorios Médicos , Piperazinas/efectos adversos , Estudios Prospectivos , Psicología , Quinolonas/efectos adversos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Resultado del Tratamiento
5.
J Clin Endocrinol Metab ; 86(12): 5674-80, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11739418

RESUMEN

Leri-Weill dyschondrosteosis (LWD) (MIM 127300) is a dominantly inherited skeletal dysplasia characterized phenotypically by Madelung wrist deformity, mesomelia, and short stature. LWD can now be defined genetically by haploinsufficiency of the SHOX (short stature homeobox-containing) gene. We have studied 21 LWD families (43 affected LWD subjects, including 32 females and 11 males, ages 3-56 yr) with confirmed SHOX abnormalities. We investigated the relationship between SHOX mutations, height deficit, and Madelung deformity to determine the contribution of SHOX haploinsufficiency to the LWD and Turner syndrome (TS) phenotypes. Also, we examined the effects of age, gender, and female puberty (estrogen) on the LWD phenotype. SHOX deletions were present in affected individuals from 17 families (81%), and point mutations were detected in 4 families (19%). In the LWD subjects, height deficits ranged from -4.6 to +0.6 SD (mean +/- SD = -2.2 +/- 1.0). There were no statistically significant effects of age, gender, pubertal status, or parental origin of SHOX mutations on height z-score. The height deficit in LWD is approximately two thirds that of TS. Madelung deformity was present in 74% of LWD children and adults and was more frequent and severe in females than males. The prevalence of the Madelung deformity was higher in the LWD vs. a TS population. The prevalence of increased carrying angle, high arched palate, and scoliosis was similar in the two populations. In conclusion, SHOX deletions or mutations accounted for all of our LWD cases. SHOX haploinsufficiency accounts for most, but not all, of the TS height deficit. The LWD phenotype shows some gender- and age-related differences.


Asunto(s)
Proteínas de Homeodominio/genética , Osteocondrodisplasias/genética , Adolescente , Adulto , Estatura , Niño , Preescolar , Femenino , Eliminación de Gen , Humanos , Masculino , Persona de Mediana Edad , Osteocondrodisplasias/complicaciones , Osteocondrodisplasias/patología , Hueso Paladar/anomalías , Fenotipo , Mutación Puntual/genética , Escoliosis/etiología , Proteína de la Caja Homeótica de Baja Estatura , Síndrome de Turner/complicaciones , Síndrome de Turner/genética , Síndrome de Turner/patología , Muñeca/anomalías
6.
FEBS Lett ; 417(2): 213-8, 1997 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-9395298

RESUMEN

We have previously isolated numerous intron-containing nuclear tRNA(Tyr) genes derived from either monocotyledonous (Triticum) or dicotyledonous (Arabidopsis, Nicotiana) plants by screening the corresponding genomic phage libraries with a synthetic tRNA(Tyr)-specific oligonucleotide. Here we have characterized additional tRNA(Tyr) genes from phylogenetically divergent plant species representing red algae (Champia), brown algae (Cystophyllum), green algae (Ulva), stonewort (Chara), liverwort (Marchantia), moss (Polytrichum), fern (Rumohra) and gymnosperms (Ginkgo) using amplification of the coding sequences from the corresponding genomic DNAs by polymerase chain reaction (PCR). All novel tRNA(Tyr) genes contain intervening sequences of variable sequence and length ranging in size from 11 to 21 bp. However, two features are conserved in all plant pre-tRNA(Tyr) introns: they possess a uridine and less frequently an adenosine at the 5' boundary and can adopt similar intron secondary structures in which an extended anticodon helix of 4-5 bp is formed by base-pairing between nucleotides of the intron and the anticodon loop. In order to elucidate the potential role of the highly conserved uridine at the first intron position, we have replaced it by all other nucleosides in an Arabidopsis pre-tRNA(Tyr) and have studied in wheat germ extract its effect on splicing and on conversion of U to psi in the GpsiA anticodon. Furthermore, we discuss the putative acquisition of tRNA(Tyr) introns at an early step of evolution after the separation of Archaea and Eucarya.


Asunto(s)
Genes de Plantas , Intrones , ARN de Transferencia de Tirosina/genética , Anticodón , Secuencia de Bases , Núcleo Celular , Endonucleasas/metabolismo , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa , Seudouridina/genética , Homología de Secuencia de Ácido Nucleico , Relación Estructura-Actividad
7.
Angew Chem Int Ed Engl ; 38(22): 3370-3373, 1999 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-10602198

RESUMEN

Unexpected stability is observed for the palladacycloheptane rac-2, which is obtained as major product and single diastereomer from the cyclization of 1 and Pd(0). Up to a temperature of 50 degrees C 2 shows neither reductive elimination nor intramolecular insertion of another olefin.

8.
Plant Mol Biol ; 38(5): 689-97, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9862487

RESUMEN

We isolated and sequenced the two major tRNA(Gln) isoacceptors with CUG and UmUG anticodons from the cytoplasm of Nicotiana rustica. These are the first tRNAs(Gln) of nuclear origin characterized in plants. The tRNA(Gln) sequences were used to design probes for the isolation of the corresponding genes from a nuclear DNA library of N. rustica. The two cloned Nicotiana tRNA(Gln) genes, coding for either of the two isoacceptors, are efficiently transcribed in HeLa cell nuclear extract. In vitro translation in the presence of purified Nicotiana tRNAs(Gln) was carried out in a wheat germ extract partially depleted of endogenous tRNAs. Cytoplasmic (cyt) tRNA(Gln)CUG and to a lesser extent cyt tRNA(Gln)UmUG stimulated readthrough over the UAG stop codon present in the tobacco mosaic virus-specific context. The two tRNA(Gln) isoacceptors are the second class of natural UAG suppressors identified in plants, in addition to cyt tRNA(Tyr)GpsiA which has previously been characterized as the first natural UAG suppressor.


Asunto(s)
Anticodón , Genes de Plantas/genética , Nicotiana/genética , Plantas Tóxicas , ARN de Transferencia de Glutamina/genética , Secuencia de Bases , Núcleo Celular/química , Núcleo Celular/metabolismo , Codón , Citoplasma/química , Citoplasma/metabolismo , Células HeLa , Humanos , Datos de Secuencia Molecular , ARN de Transferencia de Glutamina/aislamiento & purificación , Nicotiana/química , Transcripción Genética , Zeína/genética , Zeína/metabolismo
9.
G E N ; 45(3): 190-5, 1991.
Artículo en Español | MEDLINE | ID: mdl-1843951

RESUMEN

20 cases of abdominal tuberculosis (TB) were evaluated; from these, 10% with intestinal TB without peritoneal involvement and 90% presenting TB of peritoneal localization. 80% of the patients showed clinical manifestation in other organs. Pleura-lung alterations were found in 83% of the cases after X-ray chest examination. The diagnosis of abdominal TB was based on finding of caseating tuberculoid granuloma (65%), anti-TB therapeutic response (30%) and positive observation of acid-fast bacillus in sputum (5%). The conclusions from this review are that: 1) Patients with chronic illness, negative cultures and clinical evidence of infectious etiology are highly suspicious; 2) Analysis of pathologic specimens was the most accurate diagnostic method; 3) when abdominal TB is suspected a stepwise methodology must be followed to confirm diagnosis; 4) Anti-TB therapy must be started as soon as diagnosis is confirmed.


Asunto(s)
Peritonitis Tuberculosa/epidemiología , Tuberculosis Gastrointestinal/epidemiología , Adolescente , Adulto , Anciano , Antituberculosos/uso terapéutico , Niño , Quimioterapia Combinada , Femenino , Humanos , Incidencia , Laparoscopía , Laparotomía , Masculino , Persona de Mediana Edad , Peritonitis Tuberculosa/diagnóstico , Peritonitis Tuberculosa/tratamiento farmacológico , Estudios Retrospectivos , Tuberculosis Gastrointestinal/diagnóstico , Tuberculosis Gastrointestinal/tratamiento farmacológico , Venezuela/epidemiología
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