Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
J Synchrotron Radiat ; 31(Pt 2): 363-377, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38386565

RESUMEN

The ForMAX beamline at the MAX IV Laboratory provides multiscale and multimodal structural characterization of hierarchical materials in the nanometre to millimetre range by combining small- and wide-angle X-ray scattering with full-field microtomography. The modular design of the beamline is optimized for easy switching between different experimental modalities. The beamline has a special focus on the development of novel fibrous materials from forest resources, but it is also well suited for studies within, for example, food science and biomedical research.

2.
Int J Radiat Oncol Biol Phys ; 30(1): 105-15, 1994 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-7521866

RESUMEN

PURPOSE: Gliomas, squamous carcinomas and different adenocarcinomas from breast, colon and prostate might have an increased number of epidermal growth factor (EGF) receptors. The receptors are, in these cases, candidates for binding of receptor specific toxic conjugates that might inactivate cellular proliferation. The purpose of this study was to evaluate whether it is reasonable to try ligand-dextran based conjugates for therapy. METHODS AND MATERIALS: EGF or TGF alpha were conjugated to dextran and binding, internalization, retention and degradation of eight types of such conjugates were analyzed in EGF-receptor amplified glioma cells. The conjugates were labelled with radioactive nuclides to allow detection and two of the conjugates were carrying boron in the form of carboranyl amino acids or aminoalkyl-carboranes. Comparative binding tests, applying 125I-EGF, were made with cultured breast, colon and prostate adenocarcinoma, glioma and squamous carcinoma cells. Some introductory tests to label with 76Br for positron emission tomography and with 131I for radionuclide therapy were also made. RESULTS: The dextran part of the conjugates did not prevent receptor specific binding. The amount of receptor specific binding varied between the different types of conjugates and between the tested cell types. The dextran part improved intracellular retention and radioactive nuclides were retained for at least 20-24 h. The therapeutical effect improved when 131I was attached to EGF-dextran instead of native EGF. CONCLUSION: The improved cellular retention of the ligand-dextran conjugates is an important property since it gives extended exposure time when radionuclides are applied and flexibility in the choice of time for application of neutrons in boron neutron capture therapy (BNCT). It is possible that ligand-dextran mediated BNCT might allow, if the applied neutron fields covers rather wide areas around the primary tumor, locally spread cells that otherwise would escape treatment to be inactivated.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Receptores ErbB/fisiología , Neoplasias/radioterapia , Neoplasias/ultraestructura , Adenocarcinoma/radioterapia , Adenocarcinoma/ultraestructura , Animales , Compuestos de Boro/uso terapéutico , Carcinoma/radioterapia , Carcinoma/ultraestructura , Neoplasias del Colon/radioterapia , Neoplasias del Colon/ultraestructura , Dextranos/metabolismo , Portadores de Fármacos , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Glioma/radioterapia , Glioma/ultraestructura , Humanos , Radioisótopos de Yodo , Masculino , Neoplasias Mamarias Experimentales/radioterapia , Neoplasias Mamarias Experimentales/ultraestructura , Modelos Biológicos , Neoplasias Experimentales/radioterapia , Neoplasias Experimentales/ultraestructura , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/ultraestructura , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador alfa/metabolismo , Células Tumorales Cultivadas
3.
Anticancer Drugs ; 5(1): 43-52, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8186429

RESUMEN

The toxicity and binding of the three new carborane based compounds: 2 (1,2-dicarba-closo-dodecaborane (12)-1(-yl-methoxy)-2-(3-amino-propyl))-1,3-propanediol, called DAC-1; 7-(3-amino-propyl)-7,8-dicarba-nido-undecarborate (-1) called ANC-1; and rac-1-(9-o-carboranyl)-nonyl-2-methyl-glycero-3- phosphocholine, called B-Et-11-OMe, were analyzed with cultured human glioma cells, U-343MGa, and mouse melanoma cells, B16, as biological models. The previously developed compound di-sodium undecahydro-mercapto-closo-dodecarborate (BSH), which is tested for therapy of malignant gliomas, was analyzed for comparison. In the toxicity tests the cells were exposed to the substances at cell culture medium concentrations in the range 0-50 ppm boron for 1 or 20 h and thereafter analyzed regarding growth. Growth-disturbing effects were seen for the two compounds DAC-1 and B-Et-11-OMe at the concentrations corresponding to 15 and 50 ppm boron, respectively. The compounds ANC-1 and BSH showed no growth-disturbing effects at the tested concentrations. In the binding tests, the cells were incubated for 20 h at about the highest compound concentrations that did not cause growth disturbances. The boron content in the cells was then determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) and in some cases ICP-mass spectrometry (ICP-MS). The most extensive binding was seen for DAC-1 and B-Et-11-OMe, which accumulated boron to about 100 and 60 times, respectively, compared with the concentration in the culture medium. The compound ANC-1 also accumulated boron in the cells but the boron could be easily washed out indicating no or only a weak binding. BSH did not accumulate. Further analysis should be made regarding biological properties such as intracellular compartmentalization, metabolic interference and tumor specificity of the compounds DAC-1 and B-Et-11-OMe.


Asunto(s)
Boranos/toxicidad , Terapia por Captura de Neutrón de Boro , Glioma/radioterapia , Melanoma Experimental/radioterapia , Fosfatidilcolinas/toxicidad , Propilaminas/toxicidad , Animales , Boranos/farmacocinética , Compuestos de Boro/química , Compuestos de Boro/farmacocinética , Compuestos de Boro/farmacología , Supervivencia Celular/efectos de los fármacos , Glioma/metabolismo , Humanos , Espectrometría de Masas , Melanoma Experimental/metabolismo , Ratones , Fosfatidilcolinas/farmacocinética , Propilaminas/farmacocinética , Espectrometría por Rayos X , Células Tumorales Cultivadas
4.
Swed Dent J ; 17(4): 155-63, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8236033

RESUMEN

In dentistry, there is a need for better understanding of the distribution of the time spent on different activities at dental clinics. In order to investigate these resource aspects, both for the total time and for various categories of personnel and/or patients in dental clinics at the Public Dental Service (PD), Göteborg, Sweden, a time study method was used. The present study reports on the development of the PD's time study method (TSM) and analyses its functionality. The TSM, based on formulated criteria, used a method for an observer-monitored counting of frequencies. Specially trained observers registered the sampled observations for each professional, using a separate code list for each personnel group to which the professional belonged. The observer registered the on-going activity, not the duration of the procedure. Each observer followed several persons working in separated areas of the dental clinic. In 1989, the TSM was tested with the purpose of obtaining mean time values for dental care activities in the PD clinics performing general dental care. This study comprised all personnel categories in the clinic teams. Clinics were randomly selected and stratified according to the amount of dentistry for children in relation to the total time for dental care, reported as the parameter "dentist hours". Eight out of a total of 36 clinics were randomized, two from each strata.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Atención Odontológica/estadística & datos numéricos , Estudios de Tiempo y Movimiento , Asistentes Dentales , Atención Odontológica/clasificación , Atención Odontológica/organización & administración , Clínicas Odontológicas/organización & administración , Clínicas Odontológicas/estadística & datos numéricos , Higienistas Dentales , Personal de Odontología , Odontólogos , Eficiencia , Control de Formularios y Registros , Humanos , Pacientes , Proyectos Piloto , Administración de la Práctica Odontológica/organización & administración , Administración de la Práctica Odontológica/estadística & datos numéricos , Suecia/epidemiología , Factores de Tiempo
5.
Artículo en Inglés | MEDLINE | ID: mdl-2202670

RESUMEN

This report presents the clinical outcome of 47 consecutively placed Core-Vent implants inserted in 35 patients followed for 2 to 4 years by clinical and 3 to 48 months by radiographic examination. The implants were used in mandibles and maxillae to support single crowns, overdentures, and fixed prostheses splinted to natural teeth as recommended by the manufacturer. Of the 47 implants, 43 could be examined. A total of 11 implants was removed, nine because of progressive vertical bone loss and two because of fractures. The vertical bone loss was calculated for the 32 remaining implants. Twenty-eight implants demonstrated a bone loss of more than 2 mm and 16 showed a loss of more than one-third of the implant height. According to the criteria proposed by Schnitman and Shulman in 1979, the total success rate was 37.2%. When using the criteria suggested by Albrektsson et al in 1986, the total success rate was calculated to be 9.3%.


Asunto(s)
Resorción Ósea/etiología , Implantación Dental Endoósea , Implantes Dentales , Falla de Equipo , Falla de Prótesis , Adulto , Anciano , Anciano de 80 o más Años , Resorción Ósea/diagnóstico por imagen , Coronas , Pilares Dentales , Prótesis de Recubrimiento , Dentadura Parcial , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Radiografía
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...