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1.
Br J Oral Maxillofac Surg ; 53(9): 809-13, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26113044

RESUMEN

Our aim was to evaluate the efficacy of sclerotherapy using radio-opaque foam and guided by digital subtraction angiography (DSA) for complex venous malformations in the head and neck in 11 selected patients between 2011 and 2013. The sclerosing foam was manufactured by the classic Tessari method and consisted of air, 1% polidocanol, and radio-opaque media iopromide (Ultravist(®)300) in a ratio of 7:2:1. We recorded the site and size of the lesion, time and duration of treatment, and therapeutic response. The lesions were on the face, cheek, temporal region, parotid region, neck, tongue, floor of the mouth, parapharyngeal space, and soft palate. The sclerosing foam was radio-opaque under DSA, and the mean (range) dose was 21 (3-65) ml. A mean (range) of 4 (2-7) treatments was required, and 10 of the 11 patients responded well. In 4 of the 11 cases the lesion resolved completely and in 6 there was a good response. Only one lesion recurred. Early complications included immediate swelling in injected areas, snoring, and pain on swallowing, but there were no air emboli or signs of cutaneous necrosis, and the complications were self-limiting. DSA-guided sclerotherapy with radio-opaque foam was safe and effective for the treatment of complex vascular malformations of the head and neck.


Asunto(s)
Angiografía de Substracción Digital , Cabeza/irrigación sanguínea , Cuello/irrigación sanguínea , Malformaciones Vasculares , Humanos , Soluciones Esclerosantes , Escleroterapia , Resultado del Tratamiento , Malformaciones Vasculares/tratamiento farmacológico
2.
Science ; 331(6018): 736-9, 2011 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-21212318

RESUMEN

The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (100 mega-electron volts to 10 giga-electron volts) flares observed by the AGILE satellite in September 2010 and October 2007. In both cases, the total gamma-ray flux increased by a factor of three compared with the non-flaring flux. The flare luminosity and short time scale favor an origin near the pulsar, and we discuss Chandra Observatory x-ray and Hubble Space Telescope optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within an approximately 1-day time scale.

3.
Science ; 327(5966): 663-5, 2010 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-20044540

RESUMEN

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.

4.
Nature ; 462(7273): 620-3, 2009 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-19935645

RESUMEN

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated gamma-ray emission. Galactic 'microquasars', which are binary systems consisting of a neutron star or stellar-mass black hole accreting gas from a companion star, also produce relativistic jets, generally together with radio flares. Apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar, with the consequence that we are as yet unsure about the mechanism of jet energization. Here we report four gamma-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 (an exceptional X-ray binary that sporadically produces radio jets). There is a clear pattern of temporal correlations between the gamma-ray flares and transitional spectral states of the radio-frequency and X-ray emission. Particle acceleration occurred a few days before radio-jet ejections for two of the four flares, meaning that the process of jet formation implies the production of very energetic particles. In Cygnus X-3, particle energies during the flares can be thousands of times higher than during quiescent states.

5.
Hunan Yi Ke Da Xue Xue Bao ; 25(1): 65-7, 2000 Feb 28.
Artículo en Chino | MEDLINE | ID: mdl-12212254

RESUMEN

Thirty patients undergoing heart valve replacement were divided randomly into three groups (n = 10): control group, propofol group and midazolam group. Jugular bulb blood oxygen saturation (SjO2), arterialvenous oxygen content difference (Da-vO2) and cerebral oxygen extraction rate(CEO2) were measured at various periods of cardiopulmonary bypass (CPB). The results showed: SjO2 decreased significantly, Da-vO2 and CEO2 increased markedly during rewarming period in control group; but in propofol group and midazolam group, SjO2, CEO2 and Da-vO2 did not decline significantly compared with baseline. It is suggested that administering propofol or midazolam is helpful in avoiding cerebral oxygen supply and demand imbalance during CPB.


Asunto(s)
Anestésicos Intravenosos , Encéfalo/metabolismo , Puente Cardiopulmonar , Midazolam , Consumo de Oxígeno/efectos de los fármacos , Propofol , Adolescente , Adulto , Anestésicos Intravenosos/farmacología , Femenino , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Masculino , Midazolam/farmacología , Persona de Mediana Edad , Propofol/farmacología
6.
Virology ; 208(1): 111-20, 1995 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11831691

RESUMEN

Clinical and epidemiological studies have implicated the involvement of human papillomavirus (HPV) infection in cervical tumorigenesis. We have previously shown that expression of high-risk (HPV16) E6 can abrogate an important cell cycle checkpoint mediated by p53. Sublethal DNA damage causes p53 accumulation and G1 arrest in normal cells, but not in cells with mutant or absent p53, or in cells that express HPV16-E6. To investigate the functional consequences of low-risk (HPV11) E6 expression and to evaluate regions of E6 believed to mediate interaction with p53, we generated several E6 expression constructs, including HPV11-E6, and fourdifferent E6 mutants. HPV16E6 deltaD and HPV16E6 deltaB had short deletions of nucleotides encoding amino acids previously implicated in p53 degradation and binding, respectively. HPV16E6HL and HPV11E6LH had the putative p53 binding domain exchanged between the high- and the low-risk types. Unlike HPV16-E6, HPV11-E6 and the mutant E6 proteins were not able to bind or degrade p53 in in vitro assays. When expressed in RKO cells, HPV11-E6 or the mutant E6 proteins did not prevent p53 accumulation or interfere with p53-dependent WAF1/CIP1 mRNA expression, allowing p53-mediated G, cell cycle arrest after DNA damage. These findings demonstrate that low-risk and high-risk E6 proteins differ in their effects on p53-mediated cell cycle control and that rather subtle mutations of high-risk E6 can alter its ability to abrogate this important cellular response.


Asunto(s)
Mutación , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Proteína p53 Supresora de Tumor/genética , Infecciones Tumorales por Virus/virología , Ciclo Celular/genética , Transformación Celular Neoplásica , Transformación Celular Viral , Femenino , Regulación Viral de la Expresión Génica , Humanos , Papillomaviridae/fisiología , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/fisiología , Infecciones Tumorales por Virus/genética , Infecciones Tumorales por Virus/patología , Neoplasias del Cuello Uterino/virología
7.
Br J Dermatol ; 129(6): 729-32, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8286261

RESUMEN

A 25-year-old man presented with several prominent subcutaneous masses in the occipital region of the scalp. He had a long history of tinea capitis and tinea corporis infection. Histopathology of the occipital lesions showed mycelial aggregates in the deep dermis and subcutis. Cultures of the excised material and superficial scales grew a fungus identified as Microsporum ferrugineum. We propose the term 'dermatophyte pseudomycetoma' to describe this distinctive mycosis.


Asunto(s)
Dermatomicosis/microbiología , Microsporum/aislamiento & purificación , Dermatosis del Cuero Cabelludo/microbiología , Adulto , Dermatomicosis/complicaciones , Dermatomicosis/patología , Dermatomicosis/cirugía , Humanos , Masculino , Dermatosis del Cuero Cabelludo/patología , Dermatosis del Cuero Cabelludo/cirugía , Tiña del Cuero Cabelludo/complicaciones
8.
Can J Psychiatry ; 32(6): 429-32, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3500770

RESUMEN

This study assessed mood among 110 women at three phases of the menstrual cycle and its relationship with the number of reported menstrual symptoms. Women who reported fewer menstrually-related symptoms tended to have generally higher mood scores, but specific depression of mood during menses was found among the subgroup of women who reported fewer menstrual symptoms. Contraceptive pill usage was not related to mood variation across the menstrual cycle. The findings raise questions about the validity of self-reports of menstrually-related symptoms.


Asunto(s)
Afecto , Ciclo Menstrual , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Trastornos de la Menstruación/psicología , Persona de Mediana Edad , Trastornos del Humor/psicología , Pruebas Psicológicas
9.
Cancer Res ; 43(11): 5347-55, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6616469

RESUMEN

Monoclonal antibodies (MoAbs) against carcinoembryonic antigen were successfully radiolabeled with 111In, and the radiopharmaceutical was characterized in vitro and in normal and tumor-bearing mice. The 111In-MoAb proved to be stable in vitro and in vivo under normal conditions, although instability could be induced in vitro with large quantities of iron-free transferrin. Animal distribution studies with 111In-MoAb demonstrated tumor localization superior to 67Ga and pharmacokinetics that were highly similar to those of endogenously labeled 75Se-MoAb. The 111In-MoAb followed first-order kinetics and fit a two-compartmental model when studied in nude mice bearing human colon tumors known to express carcinoembryonic antigen. Significant quantities of radiolabel appeared in tissues other than tumor, with liver and skin having the highest concentrations. Sufficient tumor/background ratios were formed for scanning purposes. The data indicate that 111In-MoAb may prove to be effective as a radiopharmaceutical for tumor imaging.


Asunto(s)
Anticuerpos Monoclonales , Antígeno Carcinoembrionario/inmunología , Neoplasias del Colon/inmunología , Animales , Línea Celular , Estabilidad de Medicamentos , Humanos , Indio , Hígado/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Músculos/inmunología , Trasplante de Neoplasias , Radioisótopos , Distribución Tisular , Trasplante Heterólogo
10.
Can J Comp Med ; 40(4): 355-9, 1976 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-187303

RESUMEN

A series of investigations was designed to study the role of cellular immunity and passive antibody in protecting neonatal calves from primary bovine viral diarrhea virus infection. Administration of corticosteroids (dexamethasone) in doses capable of suppressing cellular immunity markedly potentiated systemic bovine viral diarrhea virus infection in calves which lacked bovine viral diarrhea passive neutralizing antibody. Immunosuppressed calves did not form neutralizing antibody to bovine viral diarrhea virus and developed a fatal viremia. Calves with high levels of passive bovine viral diarrhea neutralizing antibodies were protected from the effect of corticosteroids. The results suggest an essential role for humoral passive antibody, but not for cellular immunity, in protection from primary systemic bovine viral diarrhea virus infection in calves.


Asunto(s)
Animales Recién Nacidos , Enfermedades de los Bovinos/prevención & control , Dexametasona/uso terapéutico , Virus de la Diarrea Viral Bovina/inmunología , Diarrea/veterinaria , Virus ARN/inmunología , Virosis/veterinaria , Animales , Anticuerpos Antivirales/análisis , Bovinos , Diarrea/inmunología , Diarrea/prevención & control , Inmunidad Celular , Inmunidad Materno-Adquirida , Virosis/inmunología , Virosis/prevención & control
11.
Am J Vet Res ; 36(08): 1243-4, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1155841

RESUMEN

Corticosteroids given in vivo altered the response of lymphocytes in the peripheral blood of calves. Lymphocytes were cultured and stimulated in vitro with phytohemagglutinin (PHA). After an initial suppression of lymphocyte responses to PHA, there was a rapid return to normal. It is concluded that, in calves, short-term, high-dose immunosuppressive therapy with corticosteroids produces a population of lymphocytes resistant to corticosteroids, possibly by destruction of corticosteroid-sensitive lymphocytes.


Asunto(s)
Bovinos/sangre , Hidrocortisona/farmacología , Lectinas/farmacología , Activación de Linfocitos , Animales , Dexametasona/administración & dosificación , Dexametasona/farmacología , Inyecciones Intramusculares , Masculino , Timidina/metabolismo , Tritio
12.
Am J Vet Res ; 36(08): 1167-71, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1098528

RESUMEN

Swine infected with Mycobacterium bovis and Mycobacterium avium were studied for development and specificity of lymphocyte immunostimulation and tuberculin skin reactivity to purified protein derivatives (PPD) of tuberculins. Lymphocytes from infected animals had maximal blastogenic responses to PPD prepared from the homologous organisms. The time of appearance of specifically sensitized lymphocytes was studied, as was the specificity of skin reactivity. In vitro lymphocyte responses of M avium serotype 1-infected swine to M avium serotype 1 PPD were greater than were the responses of M avium serotype 2-infected swine to the same antigen. Results indicate that the specific stimulation of sensitized lymphocytes might prove useful in the diagnosis of tuberculosis in swine and in differentiating infections due to different serotypes of M avium.


Asunto(s)
Activación de Linfocitos , Mycobacterium avium/inmunología , Mycobacterium bovis/inmunología , Mycobacterium/inmunología , Enfermedades de los Porcinos/inmunología , Prueba de Tuberculina/veterinaria , Tuberculosis/veterinaria , Administración Oral , Animales , Femenino , Ganglios Linfáticos/microbiología , Mycobacterium avium/aislamiento & purificación , Mycobacterium bovis/aislamiento & purificación , Faringe , Porcinos , Enfermedades de los Porcinos/microbiología , Timidina/metabolismo , Tritio , Tuberculosis/inmunología , Tuberculosis/microbiología
13.
Am J Vet Res ; 36(5): 699-701, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-806239

RESUMEN

Lymphocyte immunostimulation tests were conducted on Mycobacterium bovis-infected and tuberculin-negative rhesus macaques (Macaca mulatta), using purified protein derivative (PPD) tuberculins prepared from strains of Mycobacterium tuberculosis and Mycobacterium avium. The stimulation of lymphocytes with M tuberculosis PPD was significantly greater for the M bovis-infected macaques than for the noninfected controls (P smaller than 0.05). The response of lymphocytes from M bovis-infected macaques to stimulation with M tuberculosis PPD was greater than the responses to stimulation with M avium PPD (P smaller than 0.01). The results of in vitro lymphocyte stimulation and tuberculin skinreactivity were similar.


Asunto(s)
Activación de Linfocitos , Macaca mulatta , Macaca , Enfermedades de los Monos/diagnóstico , Mycobacterium bovis , Prueba de Tuberculina , Tuberculosis/veterinaria , Animales , Lectinas/farmacología , Enfermedades de los Monos/inmunología , Enfermedades de los Monos/patología , Mycobacterium bovis/inmunología , Mycobacterium tuberculosis/inmunología , Factores de Tiempo , Tuberculosis/diagnóstico , Tuberculosis/inmunología
14.
Am J Vet Res ; 36(4 Pt.1): 395-8, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1092232

RESUMEN

Two calves infected with Mycobacterium avium and another 2 with Mycobacterium bovis were studied for development and specificity of lymphocyte activation responses and skin reactivity to purified protein derivatives (PPD). Lymphocytes cultured in vitro from infected calves manifested significant uptake of tritiated thymidine in response to the PPD prepared from the homologous organisms, whereas heterologous PPD produced little or no stimulation. The time of appearance of specifically sensitized lymphocytes was studied, as was the specificity of skin reactivity.


Asunto(s)
Activación de Linfocitos , Mycobacterium avium/inmunología , Mycobacterium bovis/inmunología , Mycobacterium/inmunología , Tuberculosis Bovina/inmunología , Animales , Bovinos , Lectinas/farmacología , Timidina/metabolismo , Tritio , Tuberculina/farmacología , Prueba de Tuberculina
16.
Infect Immun ; 10(3): 675-7, 1974 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-4609908

RESUMEN

Cultures of bovine peripheral blood leukocytes were prepared from calves inoculated with Mycobacterium bovis and with M. avium. Suitable lymphocyte stimulation was obtained with specific and nonspecific mycobacterial mitogens. Leukocyte cultures depleted of adherent, macrophage-type cells did not respond to stimulation with purified protein derivative, although they were responsive to phytohemagglutinin.


Asunto(s)
Activación de Linfocitos , Macrófagos/inmunología , Mycobacterium bovis/inmunología , Mycobacterium/inmunología , Animales , Antígenos Bacterianos , Bovinos , Adhesión Celular , Separación Celular , Células Cultivadas , Reacciones Cruzadas , Lectinas , Tuberculina
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