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1.
BMC Evol Biol ; 19(1): 182, 2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31533606

RESUMEN

BACKGROUND: Silkmoths and their relatives constitute the ecologically and taxonomically diverse superfamily Bombycoidea, which includes some of the most charismatic species of Lepidoptera. Despite displaying spectacular forms and diverse ecological traits, relatively little attention has been given to understanding their evolution and drivers of their diversity. To begin to address this problem, we created a new Bombycoidea-specific Anchored Hybrid Enrichment (AHE) probe set and sampled up to 571 loci for 117 taxa across all major lineages of the Bombycoidea, with a newly developed DNA extraction protocol that allows Lepidoptera specimens to be readily sequenced from pinned natural history collections. RESULTS: The well-supported tree was overall consistent with prior morphological and molecular studies, although some taxa were misplaced. The bombycid Arotros Schaus was formally transferred to Apatelodidae. We identified important evolutionary patterns (e.g., morphology, biogeography, and differences in speciation and extinction), and our analysis of diversification rates highlights the stark increases that exist within the Sphingidae (hawkmoths) and Saturniidae (wild silkmoths). CONCLUSIONS: Our study establishes a backbone for future evolutionary, comparative, and taxonomic studies of Bombycoidea. We postulate that the rate shifts identified are due to the well-documented bat-moth "arms race". Our research highlights the flexibility of AHE to generate genomic data from a wide range of museum specimens, both age and preservation method, and will allow researchers to tap into the wealth of biological data residing in natural history collections around the globe.


Asunto(s)
Bombyx/genética , Variación Genética , Filogenia , Animales , Secuencia de Bases , Sitios Genéticos , Funciones de Verosimilitud
2.
Nanotechnology ; 20(35): 355305, 2009 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-19671966

RESUMEN

Single layers of silver (Ag) nanoparticles embedded in silica (SiO2) have been fabricated by ultra-low-energy ion implantation. The distance between the Ag particles and the free SiO2 surface is controlled with nanometer precision. Raman scattering and reflectivity measurements strongly correlate to transmission electron microscopy analyses, allowing the use of these non-invasive techniques to monitor structural and dynamical properties. These results open up new opportunities to manipulate electromagnetic near-field interactions on wafer-scale plasmonic devices.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 62(1-3): 287-92, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16257727

RESUMEN

Ionisation of trimethylphosphate (TMP), dimethylphosphate (DMP) and diethylphosphate (DEP) is investigated by acidic titration in water by Raman (R), Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. The vibrational frequencies of the PO(2)(-) ionic form and the neutral form were found in accord with the literature. While increasing further H(+) concentration, the PO band disappears in the benefit of new ones. These results, together with deuteration experiments indicate the presence of a new ionic form positively charged with general formula R(1)R(2)R(3)P(OH)(+) or R(1)R(2)P(OH)(+)(2). The pK of this phosphonium entities is lying in the range -2, -4. These results were confirmed by (31)P NMR titration. The occurrence of such a phosphonium ion in aqueous solutions might be of crucial importance for biochemical reactions and interactions, owing to the large spread of phosphoryl group in biomolecules and keeping in mind that intracellular compartments are more likely concentrated media with little free water than real aqueous solutions. Furthermore, pK's can be shifted by physical-chemical parameters like dielectric constant and electric field. This may involve at least fractional positive charge apparition that might be important in biochemical regulation by charge-charge and charge-dipole interactions. This finding will gain to be further explored on more complex molecules like phospholipids, nucleic acids and proteins.


Asunto(s)
Organofosfatos/química , Organofosfonatos/química , Fosfitos/química , Espectroscopía de Resonancia Magnética/métodos , Conformación Molecular , Organofosfatos/síntesis química , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Agua
4.
Phys Rev Lett ; 94(10): 107205, 2005 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-15783518

RESUMEN

The low-spin (LS-LS, S = 0) diamagnetic form of the binuclear spin crossover complex {[Fe(bt)(NCS)(2)](2)(bpm)} was selectively photoconverted into two distinct macroscopic phases at different excitation wavelengths (1342 or 647.1 nm). These long-lived metastable phases have been identified, respectively, as the symmetry-broken paramagnetic form (HS-LS, S = 2) and the antiferromagnetically coupled (HS-HS, S = 0) high-spin form of the compound. The selectivity may be explained by the strong coupling of the primary excited states to the paramagnetic state.

5.
Gastroenterology ; 113(2): 659-63, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9247488

RESUMEN

Gastric adenocarcinoma has been previously recognized as a potential complication of familial adenomatous polyposis coli (APC) and attenuated forms of APC (AAPC). This tumor has only been reported to originate from adenomatous polyps of the gastric mucosa in these clinical conditions. There have been no previous case reports of gastric adenocarcinoma arising from the more commonly found fundic gland polyps associated with AAPC or APC. We report the first definitive case of gastric adenocarcinoma arising from a hyperplastic polyp of the fundis of a patient with AAPC.


Asunto(s)
Adenocarcinoma/etiología , Poliposis Adenomatosa del Colon/complicaciones , Pólipos/complicaciones , Neoplasias Gástricas/etiología , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Poliposis Adenomatosa del Colon/diagnóstico , Poliposis Adenomatosa del Colon/patología , Femenino , Mucosa Gástrica/patología , Humanos , Hiperplasia/patología , Persona de Mediana Edad , Pólipos/diagnóstico , Pólipos/patología , Estómago/patología , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología
8.
World J Urol ; 12(5): 266-73, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7866425

RESUMEN

In contrast to the extensive work on in vitro experiments for elucidation of the electrical properties of smooth musculature, the acquisition of knowledge on electrical signal behaviour from smooth-muscle cells in an in vivo situation remains very limited and rare. Smooth-muscle electromyographic recording from the smooth musculature of the genitourinary tract, in particular from the penile cavernous bodies and the urinary bladder, has recently become one of the most interesting issues in both impotence research as well as neurophysiological assessment of the urinary bladder. However, the inadequate available data on corpus cavernosum and EMG recordings remains controversial due to the significant discrepancy between basic physiology of the smooth musculature, technical prerequisites and the expected clinical impact from the smooth-muscle EMG of genitourinary organs. This article is an attempt to describe the fundamentals of smooth-muscle EMG signal behaviour and the technical prerequisites for data acquisition and analysis of electrical activity from smooth-muscle cells of the cavernous bodies and urinary bladder. A description is given of the technical aspects, including methodology and interpretation of the recorded data, and also of the possible interference by artefacts (endogeneous and exogeneous) that might limit the clinical relevance of this encouraging method. The advantages, pitfalls and limitations of online analogous data registration and the possibility of computer-assisted smooth-muscle electrical activity recording and analysis are demonstrated by basic in vivo studies on cavernous bodies and also the detrusor muscle.


Asunto(s)
Electromiografía , Músculo Liso/fisiología , Pene/fisiología , Vejiga Urinaria/fisiología , Animales , Procesamiento Automatizado de Datos , Humanos , Masculino
9.
Phys Rev B Condens Matter ; 48(9): 6024-6032, 1993 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10009138
10.
Ger J Ophthalmol ; 1(1): 2-6, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1477612

RESUMEN

We reviewed the results of silicone oil removal from 32 eyes that had been treated with peripheral retinectomies during vitrectomy for retinal detachment with proliferative vitreoretinopathy. With a minimum follow-up of 6 months, 3 developed a retinal detachment after silicone oil removal. Twenty-eight eyes attained a final visual acuity of 0.1 or better and 15 eyes attained 0.2 or better. Only in 3 eyes was visual acuity decreased after silicone oil removal, whereas 20 eyes showed an improvement in vision. One eye was hypotonous and 11 eyes required antiglaucomatous agents at the last examination. Final visual acuity as well as final intraocular pressure did not correlate with either the retinectomy size or with the duration of the silicone oil tamponade.


Asunto(s)
Desprendimiento de Retina/cirugía , Enfermedades de la Retina/cirugía , Aceites de Silicona , Cuerpo Vítreo/cirugía , Adolescente , Adulto , Anciano , Oftalmopatías/complicaciones , Oftalmopatías/cirugía , Femenino , Estudios de Seguimiento , Fondo de Ojo , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Desprendimiento de Retina/complicaciones , Enfermedades de la Retina/complicaciones , Resultado del Tratamiento , Agudeza Visual , Vitrectomía
11.
Fortschr Ophthalmol ; 87(3): 274-8, 1990.
Artículo en Alemán | MEDLINE | ID: mdl-2376376

RESUMEN

Retinal surgery with implantation of silicone oil was performed in 33 patients presenting with idiopathic or traumatic proliferative vitreoretinopathy. Following removal of the oil patients were on average followed-up for 6 to 29 months (14 months). Sixteen patients had had buckling procedures prior to endosurgery. Improvement of vision up to 4 rows of optotypes was noted in 21 patients following silicone oil removal. Three cases showed a large, organic, central scotoma. Ten patients suffered from diplopia; 3 of whom were known to have had a preexisting strabismus. Suppression of the visual impression of the operated eye was seen in 4 cases. Eye muscle surgery was necessary in 4 cases. Sixteen patients demonstrated normal binocular vision as far as possible taking the visual acuity into account.


Asunto(s)
Desprendimiento de Retina/cirugía , Neovascularización Retiniana/cirugía , Visión Binocular/fisiología , Agudeza Visual/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Curvatura de la Esclerótica/métodos , Aceites de Silicona/administración & dosificación , Vitrectomía/métodos
13.
Acta Endocrinol (Copenh) ; 116(1): 129-37, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3661052

RESUMEN

Previous experiments have suggested that sleep processes are sensitive to influences of corticosteroids. The present experiment was designed to compare effects of three different corticosteroids on human sleep: fluocortolone (a synthetic pure glucocorticoid), cortisol which possesses glucocorticoid and mineralocorticoid activity, and aldosterone (the major mineralocorticoid). Ten male adult subjects were tested in four experimental nights according to a double-blind latin-square design under conditions of either 1.0 mg of aldosterone, 20 mg of fluocortolone, 80 mg of hydrocortisone, or placebo. Substances were administered orally (fluocortolone, 23.00 h) or infused iv throughout the night (hydrocortisone, aldosterone) starting at 23.00 h. Hydrocortisone and fluocortolone induced a substantial reduction of rapid eye movement sleep. Hydrocortisone increased slow wave sleep activity. No such effect was observed after fluocortolone. Effects on sleep processes of aldosterone, in general, seemed to be neglegible. The results demonstrate differential effects of synthetic glucocorticoid, cortisol, and aldosterone on sleep in humans, which may be attributed to the heterogeneity of corticosteroid receptors in the brain.


Asunto(s)
Aldosterona/farmacología , Fluocortolona/farmacología , Hidrocortisona/farmacología , Receptores de Glucocorticoides/efectos de los fármacos , Sueño/efectos de los fármacos , Administración Oral , Adulto , Método Doble Ciego , Humanos , Inyecciones Intravenosas , Masculino
15.
Prostate ; 5(3): 231-54, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6374638

RESUMEN

These studies were initiated with the objective of isolating epithelial and stromal cells of human prostatic tissue in undamaged state, in order to study the cellular distribution of steroid receptors in benign prostatic hyperplasia (BPH) relative to normal prostate. Initial experiments showed that when BPH tissue immersed in tissue culture media was progressively fragmented by various cutting procedures, epithelial elements were selectively released as clumps of variable size and individual cells, but that a large percentage of these cells were damaged, as evidenced by their failure to exclude trypan blue (TB). These observations suggested that if tissue fragmentation were carried out under defined conditions that minimize cell damage, BPH subfractions might be obtained containing a large percentage of undamaged cells. To determine conditions of tissue fragmentation which result in maximal recovery of epithelial cells which exclude TB, rat ventral prostate (RVP) was chosen as a model system. Experiments with RVP revealed that maximal yields of such cells were obtained in "large" epithelial clumps (greater than 30 cells per clump) released under the following conditions: (1) chopping the tissue with razor blades in a large volume (2 ml/100 mg RVP) of a Ca2+-free tissue culture medium ( Joklik 's-MEM) containing 1% casein, (2) carrying out the entire fractionation procedure in the cold, and (3) maintaining a 1% casein concentration in the medium during chopping, as well as in subsequent washing procedures, to protect cells from proteolytic activity. In large epithelial clumps, cells in the interior of the clump were not stained by TB but the cells at the periphery of the clump were freely permeable to TB. Single epithelial cells and small epithelial clumps (3-10 cells) released by razor blade fragmentation were also permeable to TB. When large epithelial clumps were incubated at 20 degrees C for 90 min, the clumps disaggregated into smaller clumps and morphologically intact single cells, which did not exclude TB. The residual tissue fragments remaining after chopping contained the bulk of stromal cells plus some epithelial elements. The latter could be removed by gentle rubbing of the fragments on a sieve in the presence of medium. The stromal fraction thus obtained consisted of stromal cells, embedded in mesenchymal matrix, which were not stained by TB and appeared normal when examined histologically by light microscopy.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Próstata/citología , Fosfatasa Ácida/análisis , Animales , Caseínas/farmacología , Castración , Fraccionamiento Celular , Frío , Medios de Cultivo , Técnicas Citológicas , ADN/análisis , Células Epiteliales , Masculino , Próstata/análisis , Ratas , Ratas Endogámicas , Receptores Androgénicos/análisis , Receptores de Estrógenos/análisis , Azul de Tripano
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