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1.
J Sex Med ; 13(10): 1546-54, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27641922

RESUMEN

INTRODUCTION: Neuroimaging and other studies have changed the common view that pedophilia is a result of childhood sexual abuse and instead is a neurologic phenomenon with prenatal origins. Previous research has identified differences in the structural connectivity of the brain in pedophilia. AIM: To identify analogous differences in functional connectivity. METHODS: Functional magnetic resonance images were recorded from three groups of participants while they were at rest: pedophilic men with a history of sexual offenses against children (n = 37) and two control groups: non-pedophilic men who committed non-sexual offenses (n = 28) and non-pedophilic men with no criminal history (n = 39). MAIN OUTCOME MEASURE: Functional magnetic resonance imaging data were subjected to independent component analysis to identify known functional networks of the brain, and groups were compared to identify differences in connectivity with those networks (or "components"). RESULTS: The pedophilic group demonstrated wide-ranging increases in functional connectivity with the default mode network compared with controls and regional differences (increases and decreases) with the frontoparietal network. Of these brain regions (total = 23), 20 have been identified by meta-analytic studies to respond to sexually relevant stimuli. Conversely, of the brain areas known to be those that respond to sexual stimuli, nearly all emerged in the present data as significantly different in pedophiles. CONCLUSION: This study confirms the presence of significant differences in the functional connectivity of the brain in pedophilia consistent with previously reported differences in structural connectivity. The connectivity differences detected here and elsewhere are opposite in direction from those associated with anti-sociality, arguing against anti-sociality and for pedophilia as the source of the neuroanatomic differences detected.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Pedofilia/patología , Delitos Sexuales , Adulto , Nivel de Alerta/fisiología , Encéfalo/fisiopatología , Estudios de Casos y Controles , Niño , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Conducta Sexual
2.
Neurobiol Dis ; 34(2): 389-95, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19268537

RESUMEN

Huntington's Disease is a neurodegenerative condition caused by a polyglutamine expansion in the huntingtin (Htt) protein, which aggregates and also causes neuronal dysfunction. Pathogenic N-terminal htt fragments perturb axonal transport in vitro. To determine whether this occurs in vivo and to elucidate how transport is affected, we expressed htt exon 1 with either pathogenic (HttEx1Q93) or non-pathogenic (HttEx1Q20) polyglutamine tracts in Drosophila. We found that HttEx1Q93 expression causes axonal accumulation of GFP-tagged fast axonal transport vesicles in vivo and leads to aggregates within larval motor neuron axons. Time-lapse video microscopy, shows that vesicle velocity is unchanged in HttEx1Q93-axons compared to HttEx1Q20-axons, but vesicle stalling occurs to a greater extent. Whilst HttEx1Q93 expression did not affect locomotor behaviour, external heat stress unveiled a locomotion deficit in HttEx1Q93 larvae. Therefore vesicle transport abnormalities amidst axonal htt aggregation places a cumulative burden upon normal neuronal function under stressful conditions.


Asunto(s)
Transporte Axonal/genética , Axones/metabolismo , Sistema Nervioso Central/metabolismo , Drosophila/metabolismo , Neuronas Motoras/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Animales , Axones/patología , Temperatura Corporal/genética , Sistema Nervioso Central/patología , Sistema Nervioso Central/fisiopatología , Drosophila/genética , Femenino , Trastornos Neurológicos de la Marcha/genética , Trastornos Neurológicos de la Marcha/metabolismo , Trastornos Neurológicos de la Marcha/fisiopatología , Trastornos de Estrés por Calor/genética , Trastornos de Estrés por Calor/metabolismo , Trastornos de Estrés por Calor/fisiopatología , Humanos , Proteína Huntingtina , Enfermedad de Huntington/genética , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/fisiopatología , Masculino , Neuronas Motoras/patología , Péptidos/genética , Péptidos/metabolismo , Estrés Fisiológico/genética , Vesículas Transportadoras/metabolismo , Vesículas Transportadoras/patología
3.
Opt Lett ; 31(19): 2833-5, 2006 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-16969393

RESUMEN

We demonstrate a Q-switched, cladding-pumped, Nd:Al-doped silica depressed clad hollow optical fiber (DCHOF) laser, which generated up to 133 microJ of pulse energy at a repetition rate of 5 kHz and 0.9 W of average output power at a high repetition rate (>20 kHz) in a diffraction-limited beam (M(2)=1.08) at 927 nm. The laser was tunable from 919 to 935 nm. This result shows the potential of the DCHOF structure for the suppression of unwanted long-wavelength radiation in large-area cores suitable for high-power Q-switched laser operation.

4.
Opt Lett ; 30(22): 2997-9, 2005 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-16315700

RESUMEN

We present a cladding-pumped single-frequency, single-mode erbium:ytterbium codoped fiber master-oscillator power amplifier source generating up to 151 W of continuous-wave output power at 1563 nm with 33% slope efficiency and 20 dB gain. This source was also tunable and had a stable operation range of 1546 to 1566 nm at an output power level in excess of 125 W. The doped fiber exploited a large-core design for improved power handling and mitigation of stimulated Brillouin scattering. There was no sign of having stimulated Brillouin scattering even at the highest power. Despite a large core (V = 12), the output beam was nearly diffraction limited (M2 = 1.1). The source showed slight rollover at over 100 W of output power because of the onset of emission from ytterbium, centered at 1060 nm.

5.
Opt Lett ; 30(9): 955-7, 2005 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15906968

RESUMEN

We demonstrate a cladding-pumped single-mode plane-polarized ytterbium-doped fiber laser generating 633 W of continuous-wave output power at 1.1 microm with 67% slope efficiency and a polarization extinction ratio better than 16 dB. The laser is end pumped through both fiber ends and shows no evidence of roll-over, even at the highest output power, which is limited only by the available pump power.

6.
Opt Lett ; 30(5): 459-61, 2005 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15789702

RESUMEN

We present a single-frequency, single-mode, plane-polarized ytterbium-doped all-fiber master oscillator power amplifier source at 1060 nm generating 264 W of continuous-wave output power. The final-stage amplifier operated with a high gain of 19 dB and a high conversion efficiency of 68%. There was no evidence of rollover from stimulated Brillouin scattering even at the highest output power, and the maximum output was limited only by the available pump power.

7.
Br J Anaesth ; 86(3): 427-30, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11573536

RESUMEN

Septal dyskinesia in the left ventricle is detected frequently in many patients after open-heart surgery. The present study was designed to determine whether the antegrade delivery of cardioplegic solution to the regional wall categorized in echocardiography is homogeneous, and whether the distribution to the septal wall differs from that to the lateral wall in the absence of coronary artery disease. To assess these hypotheses quantitatively, radioactive microspheres were mixed into the cardioplegic solution and infused by an antegrade method in eight normal pigs. The cardioplegic distribution to the septal wall was significantly less than to the lateral wall close to the base of the left ventricle (P<0.05). Therefore, antegrade perfusion of cardioplegic solution was non-uniformly distributed to the regional and transmural wall of normal pig hearts. Absence of functional correlation was a limitation of this study. However, these findings suggest that inadequate protection of the ventricular septum by antegrade cardioplegia might be an explanation for the abnormalities of septal wall motion after open-heart surgery.


Asunto(s)
Soluciones Cardiopléjicas/farmacocinética , Miocardio/metabolismo , Animales , Ecocardiografía , Tabiques Cardíacos/metabolismo , Ventrículos Cardíacos/metabolismo , Microesferas , Porcinos
8.
Biochem Biophys Res Commun ; 283(2): 369-73, 2001 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-11327710

RESUMEN

We have developed a solid matrix immunoassay to determine the binding of interleukin-2 (IL-2) to specific gangliosides. The assay establishes that recombinant human IL-2 binds to ganglioside GD(1b) but not to any other gangliosides (GM(1), GM(2), GM(3), GD(1a), GD(2), GD(3), and GT(1b)). The binding varies with the ratio of GD1b and IL-2. This assay enables distinguishing the nature of the sugar moiety of the ganglioside recognized by IL-2 and establishes the dosimetry of the ganglioside-IL-2 interaction. Since rIL-2 is administered systematically into stage IV melanoma patients, we have examined 45 tumor biopsies for GD(1b) content. The incidence of GD(1b) in tumor biopsies is 51%. We postulate that GD(1b) associated on the tumor or in the circulation of cancer patients may bind to rIL-2 and prevent the availability of rIL-2 to augment antitumor-immune response.


Asunto(s)
Gangliósidos/metabolismo , Interleucina-2/metabolismo , Sitios de Unión , Gangliósidos/uso terapéutico , Humanos , Inmunoensayo/métodos , Técnicas In Vitro , Cinética , Melanoma/tratamiento farmacológico , Melanoma/inmunología , Melanoma/metabolismo , Unión Proteica , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapéutico
9.
Anticancer Res ; 20(5A): 3083-92, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11062726

RESUMEN

BACKGROUND: Several investigators have proposed that carcinoembryonic antigen (CEA), an immunogenic antigen expressed by colon carcinoma, may also be expressed by human melanoma. Because sialyl Lewisx (sLex), the carbohydrate moiety of CEA, has been identified in melanoma, we compared CEA and sLex levels in colon carcinoma cells and melanoma cells. METHODS: CEA levels were assessed for expression on the cell surface and in cell lysates of cutaneous melanoma cell lines by two different kinds of ELISA, and by Western blot analysis of immunoprecipitated CEA using monoclonal antibodies (Mabs) T84-66 and COL-1, which have defined specificities for CEA. Colon carcinoma cells and purified CEA were positive controls. RESULTS: Both Mabs reacted strongly with cell surface and cell lysates of colon cancer. Mab T84-66 reacted well with cell surface but not cell lysates of melanoma. COL-1 reacted poorly with cell surface but its binding increased with the density of melanoma cell lysates. Both Mabs intensely stained the blots of purified CEA and colon carcinoma lysates immunoprecipitated with the respective Mabs, but failed to stain the immunoprecipitates of melanoma cell lysates. Both Mabs bound to lysates immunoprecipitated with anti-sLex Mab in colon carcinoma, but not in melanoma. Cell-surface expression of CEA and sLex was significantly correlated (r2: 0.88) in colon cancer cells but not in melanoma. CONCLUSION: Our results confirm the presence of CEA in colon carcinoma but not in human cutaneous melanoma cell lines.


Asunto(s)
Antígeno Carcinoembrionario/biosíntesis , Melanoma/inmunología , Neoplasias Cutáneas/inmunología , Animales , Western Blotting/métodos , Neoplasias del Colon/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Ratones , Oligosacáridos/metabolismo , Pruebas de Precipitina/métodos , Antígeno Sialil Lewis X , Células Tumorales Cultivadas
10.
Cancer ; 88(8): 1828-36, 2000 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10760759

RESUMEN

BACKGROUND: Pancreatic adenocarcinoma cells express gangliosides and sialyl Lewis (sLe) antigens. It is not known whether these carbohydrate antigens can be targeted by immunotherapy. The authors measured the expression of GM(2) and sLe antigens on the surface of pancreatic carcinoma cells and the serum levels of total gangliosides, GM(2), and antiganglioside antibodies in patients with pancreatic carcinoma. METHODS: Cell surface GM(2) and sLe antigens were measured by cell suspension enzyme linked immunoadsorbent assay (ELISA) in four pancreatic carcinoma cell lines. Sera from 20 pancreatic carcinoma patients and 20 age- and gender-matched healthy volunteers were analyzed for antiganglioside and anti-sLe immunoglobulin (Ig) M titers by ELISA. Serum levels of total gangliosides and GM(2) also were measured. RESULTS: All cell lines expressed GM(2) and sLe antigens. When compared with age- and gender-matched volunteers, patients had significantly higher serum levels of total gangliosides (25.6 +/- 9.0 mg/dL vs. 15.6 +/- 2.7 mg/dL; P < 0.001), GM(2) (0.278 +/- 0.415 mg/dL vs. 0.013 +/- 0.018 mg/dL; P = 0.02), ELISA units of anti-GM(2) IgM antibody (368 +/- 95 vs. 155 +/- 25; P = 0.04) and anti-GD(1b) IgM antibody (351 +/- 91 vs. 138 +/- 26; P = 0.03), but not anti-sLe(x) IgM (1389 +/- 345 vs. 1081 +/- 224; P = 0.46) or anti-sLe(a) IgM antibody (1097 +/- 253 vs. 1200 +/- 315; P = 0.80). Patients with unresectable tumors had higher serum levels of total gangliosides compared with patients with resectable tumors, and a serum level > 25 mg/dL was found to correlate significantly with poor overall survival (P < 0.02). CONCLUSIONS: Increased serum levels of total gangliosides and GM(2) may reflect shedding or release of gangliosides from the surface of tumor cells. Production of IgM antibody against GM(2) and GD(1b) indicates that these gangliosides are immunogenic antigens that may be potential targets for effective active immunotherapy.


Asunto(s)
Adenocarcinoma/inmunología , Gangliósido G(M2)/sangre , Gangliósidos/sangre , Neoplasias Pancreáticas/inmunología , Adenocarcinoma/fisiopatología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Ensayo de Inmunoadsorción Enzimática , Femenino , Gangliósido G(M2)/inmunología , Gangliósidos/inmunología , Humanos , Inmunoglobulina M/análisis , Inmunoterapia , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/fisiopatología , Neoplasias Pancreáticas/terapia , Células Tumorales Cultivadas
11.
Indian J Exp Biol ; 38(4): 301-12, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11218805

RESUMEN

This review discusses the immunology of gangliosides from the perspective of tumor, neuronal and general immunology. Antiganglioside antibodies in human sera are invariably IgM and are found in healthy individuals. Their titers decline with age. Persistent high titer of IgM is associated with several diseases, particularly neuropathies. Membrane-bound gangliosides are important tumor-associated antigens and targets for immune attack. Cells enriched with gangliosides can be used as cancer vaccines. Efficacy of these vaccines depends on the viability of whole cells, integrity of the cell membranes, adjuvants and topography of the tumor-associated antigens. The role of antiganglioside IgM is to eliminate the immunosuppressive gangliosides shed from tissues during ageing, degeneration of neural and extraneural tissues, and tumor growth and necrosis. In addition, in vitro observations with human and murine monoclonal antibodies suggest that they are capable of complement dependent cytotoxicity and apoptosis.


Asunto(s)
Gangliósidos/inmunología , Animales , Antígenos/química , Autoanticuerpos/sangre , Biomarcadores , Secuencia de Carbohidratos , Gangliósidos/química , Humanos , Inmunoglobulina M/sangre , Ratones , Datos de Secuencia Molecular
12.
J Nematol ; 21(2): 184-8, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19287597

RESUMEN

Three nematicides were evaluated as seed treatments to control the alfalfa stem nematode (Ditylenchus dipsaci) on seedling alfalfa. Alfalfa seeds were soaked for 10 hours in a 0.5% (formulated by weight) concentration of either carbofuran, phenamiphos or oxamyl in acetone with no adverse effect on seed germination. All three treatments decreased nematode damage and increased survival of 'Ranger' (susceptible) and 'Lahontan' (resistant) alfalfa plants, when seeds were planted in soil infested with D. dipsaci. Mean live plant counts after 6 weeks in the untreated control, acetone alone, carbofuran, phenamiphos, and oxamyl treatments, respectively, were 4.3, 6.3, 19.0, 19.8, and 19.0 for Lahontan and 4.5, 1.5, 18.5, 19.3, and 18.0 for Ranger from 20 seeds/pot. Nematicide seed treatments resulted in significantly healthier Ranger alfalfa plants 4 months after planting. The combination of seed treatment and host resistance may provide a means of establishing alfalfa in an alfalfa monocropped system where soil populations of D. dipsaci are high.

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