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1.
Breast Cancer Res Treat ; 168(3): 739-744, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29335922

RESUMEN

PURPOSE: Mastectomy is the standard procedure in patients with in-breast tumor recurrence (IBTR) or breast cancer after irradiation of the chest due to Hodgkin's disease. In certain cases a second breast conserving surgery (BCS) in combination with intraoperative radiotherapy (IORT) is possible. To date, data concerning BCS in combination with IORT in pre-irradiated patients are limited. This is the first pooled analysis of this special indication with a mature follow-up of 5 years. METHODS: Patients with IBTR after external beam radiotherapy (EBRT; treated in two centers) for breast cancer were included. Patients with previous EBRT including the breast tissue due to other diseases were also included. IORT was performed with the Intrabeam™-device using low kV X-rays. Clinical data including outcome for all patients and toxicity for a representative cohort (LENT-SOMA scales) were obtained. Statistical analyses were done including Kaplan-Meier estimates for local recurrence, distant metastasis and overall survival. RESULTS: A total of 41 patients were identified (39 patients with IBTR, 2 with Hodgkin`s disease in previous medical history). Median follow-up was 58 months (range 4-170). No grade 3/4 acute toxicity occurred within 9 weeks. Local recurrence-free survival rate was 89.9% and overall survival was 82.7% at 5 years. Seven patients developed metastasis within the whole follow-up. CONCLUSIONS: BCS in combination with IORT in IBTR in pre-irradiated patients is a feasible method to avoid mastectomy with a low risk of side effects and an excellent local control and good overall survival.


Asunto(s)
Neoplasias de la Mama/cirugía , Mama/cirugía , Recurrencia Local de Neoplasia/cirugía , Radioterapia Adyuvante/métodos , Adulto , Anciano , Mama/patología , Mama/efectos de la radiación , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Terapia Combinada/efectos adversos , Supervivencia sin Enfermedad , Femenino , Humanos , Cuidados Intraoperatorios , Mastectomía , Mastectomía Segmentaria/efectos adversos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/radioterapia
2.
Dis Esophagus ; 25(3): 256-62, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21899651

RESUMEN

The purpose of this study was to report the outcome of radio(chemo)therapy in the curative management of esophageal squamous cell carcinoma (ESCC). We retrospectively analyzed 163 patients with T1-T4, N0-1, M0 ESCC who were treated between January 1988 and December 2006 at the Technische Universität München. One hundred sixty patients were inoperable due to a poor performance status, comorbidities or locally advanced unresectable disease. External beam radiation therapy (EBRT) was performed with (n= 146) or without (n= 17) systemic chemotherapy. Fifty-four patients received an additional boost with intraluminal brachytherapy (IBT). Surviving patients were followed for a median of 72 months (range 10-173 months). The estimated overall survival (OS) at 2 and 5 years was 27 ± 4% and 11 ± 3%, respectively. Loco-regional recurrence at the primary site was observed in 29% of patients (n= 47). The recurrence-free survival (RFS) at 2 and 5 years was 24 ± 3% and 9 ± 2%, respectively. In multivariate analyses, the ECOG performance status (P= 0.004), 3D conformal (vs conventional) radiotherapy (P= 0.031) and continuous standard fractionation (vs split-course radiotherapy, P= 0.048) were associated with a better OS. Simultaneous chemotherapy (P= 0.49) or IBT (P= 0.31) had no significant impact on survival. Outcome for patients with ESCC is poor. Despite the very unfavorable patient selection (poor performance status, high rate of comorbidities, and advanced disease), long-term survival with radio(chemo)therapy was achieved in about 10% of patients. The introduction of modern treatment techniques/modalities (3D conformal planning/ continuous standard fractionation) might be associated with better outcomes.


Asunto(s)
Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/radioterapia , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/radioterapia , Recurrencia Local de Neoplasia/patología , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia , Carcinoma de Células Escamosas/tratamiento farmacológico , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Neoplasias Esofágicas/tratamiento farmacológico , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Metástasis de la Neoplasia , Modelos de Riesgos Proporcionales , Planificación de la Radioterapia Asistida por Computador , Radioterapia Conformacional , Estudios Retrospectivos , Resultado del Tratamiento
3.
Pharmazie ; 67(1): 91-4, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22393838

RESUMEN

Xanthohumol, the most abundant prenylated chalcone in hop (Humulus lupulus L.) cones, is well known to exert several promising pharmacological activities in vitro and in vivo. Among these, the chemopreventive, anti-inflammatory and anti-cancer effects are probably the most interesting. As xanthohumol is hardly soluble in water and able to undergo conversion to isoxanthohumol we determined several handling characteristics for cell culture work with this compound. Recovery experiments revealed that working with xanthohumol under cell culture conditions requires a minimal amount of 10% FCS to increase its solubility to reasonable concentrations (-50-75 micromol/l) for pharmacological in vitro tests. Additionally, more than 50% of xanthohumol can be absorbed to various plastic materials routinely used in the cell culture using FCS concentrations below 10%. In contrast, experiments using fluorescence microscopy in living cells revealed that detection of cellular intake of xanthohumol is hampered by concentrations above 1% FCS.


Asunto(s)
Células Cultivadas , Flavonoides/farmacología , Propiofenonas/farmacología , Línea Celular , Cromatografía Líquida de Alta Presión , Técnicas Citológicas , Flavonoides/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Microscopía Fluorescente , Microscopía de Contraste de Fase , Propiofenonas/metabolismo , Solubilidad
4.
J Mol Endocrinol ; 6(2): 137-45, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1645971

RESUMEN

The effects of pregnancy or progesterone dominance on the beta-adrenergic responsiveness of the uterus were studied in myometrial membranes from mid- and late-pregnant rats (day 15 and on the 16th h of day 22 of pregnancy respectively) or 24 h after administration of progesterone. Levels of the high (RH)- and low (RL)-affinity states of the beta-adrenergic receptor were determined by competition experiments between 125I-labelled cyanopindolol binding and the selective beta-agonist isoproterenol. The ratio KL/KH (respective dissociation constants) was determined since it also reflects the degree of formation of the high-affinity state of the beta-adrenergic receptor. From day 15 to the 10th h of day 22 of pregnancy, two distinct affinity states were apparent: 80-55% RH (KH = 0.31-0.21 microM) and 45-20% RL (KL = 14-5 microM) with a ratio of KL/KH of 55-34. In the last 6 h before birth, beta-adrenergic receptors underwent uncoupling which was paralleled by decreased responsiveness of myometrial adenylate cyclase to isoproterenol (maximum velocity (Vmax) = 17 +/- 3 vs 44 +/- 3 fmol cyclic AMP/10 min per mg protein on day 15). At this stage of pregnancy, previous exposure to progesterone resulted in a 1.8-fold increase in 125I-labelled cyanopindolol-binding sites (Bmax) and the reappearance of the high-affinity state (67% RH, KH = 0.19 +/- 0.04 (S.E.M.) microM, ratio KL/KH = 81.1 +/- 16.9).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Adenilil Ciclasas/metabolismo , Miometrio/metabolismo , Preñez/metabolismo , Progesterona/farmacología , Receptores Adrenérgicos beta/metabolismo , Animales , Membrana Celular/metabolismo , Femenino , Yodocianopindolol , Isoproterenol/farmacología , Cinética , Mifepristona/farmacología , Pindolol/análogos & derivados , Pindolol/metabolismo , Embarazo , Ratas , Ratas Endogámicas , Receptores Adrenérgicos beta/efectos de los fármacos , Valores de Referencia
5.
Int J Radiat Oncol Biol Phys ; 34(3): 599-608, 1996 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-8621284

RESUMEN

PURPOSE: The study was aimed at the measurement of effect-depth distributions of intracellularly induced DNA damage in water as tissue equivalent after heavy ion irradiation with therapy particle beams. METHODS AND MATERIALS: An assay involving embedding of Chinese hamster ovary (CHO-K1) cells in large agarose plugs and electrophoretic elution of radiation induced DNA fragments by constant field gel electrophoresis was developed. Double-strand break production was quantified by densitometric analysis of DNA-fluorescence after staining with ethidium-bromide and determination of the fraction of DNA eluted out of the agarose plugs. Intracellular double-strand break induction and the effect of a 3 h rejoining incubation were investigated following irradiation with 250 kV x-rays and 109 MeV/u carbon- and 295 MeV/u neon-ions. RESULTS AND CONCLUSION: While the DNA damage induced by x-irradiation decreased continuously with penetration depth, a steady increase in the yield of double-strand breaks was observed for particle radiation, reaching distinct maxima at the position of the physical Bragg peaks. Beyond this, the extent of radiation damage dropped drastically. From comparison of DNA damage and calculated dose profiles, relative biological efficiencies (RBEs) for both double-strand break induction and unrejoined strand breaks after 3 h were determined. While RBE for the induction of DNA double-strand breaks decreased continuously with penetration depth, RBE maxima greater than unity were found with carbon- and neon-ions for double-strand break rejoining near the maximum range of the particles. The method presented here allows for a fast and accurate determination of depth profiles of relevant radiobiological effects for mixed particle fields in tissue equivalent.


Asunto(s)
Carbono , Daño del ADN , ADN/metabolismo , ADN/efectos de la radiación , Neón , Animales , Células CHO/efectos de la radiación , Cricetinae , Reparación del ADN , Líquido Intracelular/metabolismo , Transferencia Lineal de Energía , Aceleradores de Partículas , Agua/química , Rayos X
6.
Radiat Res ; 135(1): 46-55, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8327660

RESUMEN

The induction of intracellular DNA strand breaks by X rays and various heavy charged particles was measured by the alkaline unwinding and alkaline and neutral filter elution techniques. No variations in strand break induction were found between the different cell lines under investigation. For a given particle, both the LET and the particle energy determined the efficiency to induce DNA lesions. RBE values for the total amount of induced strand breaks were always less than 1. For DNA double-strand breaks (DSBs), RBE values only slightly greater than 1 were determined for particle radiation with an LET around 300 keV/microns. Intracellular DSB/SSB ratios were found to be equivalent to data reported for in vitro systems using radioprotective conditions [Christensen et al., Int. J. Radiat. Biol. 22, 457-477, 1972; Taucher-Scholz et al., Adv. Space Res. 12(2-3), (2)73-(2)80, 1992]. Strand break rejoining as an indicator of cellular repair processes was detected even after high-LET irradiation (LET < or = 10,000 keV/microns). However, both the half-times of rejoining and the fraction of residual DNA breaks increased with the atomic number of the particle. After particle irradiation with LET values beyond 10,000 keV/microns, no rejoining of DNA strand breaks was found.


Asunto(s)
Daño del ADN/efectos de la radiación , Animales , Bovinos , Línea Celular , Células Cultivadas , Cricetinae , Cricetulus , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Humanos , Iones , Níquel/química , Uranio/química , Rayos X
7.
Phytochemistry ; 54(5): 531-7, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10939358

RESUMEN

From the methanol extract of the roots of (Crossopetalum gaumeri, four new highly cytotoxic cardenolides, securigenin-3beta-O-beta-6-deoxyguloside (2), 19-hydroxy-sarmentogenin-3beta-O-beta-6-deoxyguloside (4), sarmentogenin-3beta-O-[alpha-allosyl-(1-->4)-beta-6-deoxy alloside] (5), and securigenin-3beta-O-[alpha-allosyl-(1-->4)-beta-6-deoxyal loside] (6) were isolated. The dichloromethane extract afforded the new diterpene 3,15-dihydroxy-18-norabieta-3,8,11,13-tetraene (7) as well as the new triterpene 2,3,7-trihydroxy-6-oxo-1,3,5(10),7-tetraene-24-nor-friedelane-29-o ic acid methylester (11). The new terpenoids lack cytotoxicity and the antibacterial activity is moderate to low.


Asunto(s)
Antibacterianos/aislamiento & purificación , Cardenólidos/aislamiento & purificación , Citotoxinas/aislamiento & purificación , Plantas Medicinales , Terpenos/aislamiento & purificación , Antibacterianos/química , Antibacterianos/farmacología , Bacillus cereus/efectos de los fármacos , Cardenólidos/química , Cardenólidos/farmacología , Supervivencia Celular/efectos de los fármacos , Citotoxinas/química , Citotoxinas/toxicidad , Escherichia coli/efectos de los fármacos , Humanos , Células KB , Metanol , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Raíces de Plantas/química , Staphylococcus epidermidis/efectos de los fármacos , Relación Estructura-Actividad , Terpenos/química , Terpenos/toxicidad
8.
Phytochemistry ; 57(8): 1281-5, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11454360

RESUMEN

A new cytotoxic 1,7-dioxa-dispiro[5.1.5.2]pentadeca-9,12-dien-11-one derivative, aculeatin D, and a new alkenone, 5-hydroxy-hexacos-1-en-3-one, have been isolated as minor compounds from the rhizomes of Amomum aculeatum. Their structures have been determined mainly by NMR spectroscopy and mass spectrometry. Aculeatin D showed high cytotoxicity against the KB and the L-6 cell line with IC(50) of 0.38 microg/ml and 1 microg/ml, respectively. Additionally, it revealed remarkable activity against two Plasmodium falciparum strains, as well as against Trypanosoma brucei rhodesiense and Trypanosoma cruzi. 5-Hydroxy-hexacos-1-en-3-one exhibited neither cytotoxic nor antiprotozoal activity, whereas antibacterial testing against Bacillus cereus, Escherichia coli and Staphylococcus epidermidis showed moderate to strong activity for both compounds.


Asunto(s)
Alquenos/aislamiento & purificación , Antiinfecciosos/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Cetonas/aislamiento & purificación , Plantas Medicinales/química , Compuestos de Espiro/aislamiento & purificación , Alquenos/química , Alquenos/farmacología , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/farmacología , Línea Celular , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Cetonas/química , Cetonas/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Nueva Guinea , Tallos de la Planta/química , Ratas , Compuestos de Espiro/química , Compuestos de Espiro/farmacología
9.
Phytochemistry ; 55(8): 941-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11140529

RESUMEN

Four new bisanthraquinone glycosides, S-(+)-skyrin-6-O-beta-glucopyranoside (1), R-(-)-skyrin-6-O-beta-glucopyranoside (2), S-(+)-skyrin-6-O-beta-xylopyranoside (3) and S-(+)-skyrin-6-O-beta-alpha-arabinofuranoside (4), have been isolated from an ethanol-water (1:1, v/v) dry extract of the aerial parts of Hypericum perforatum L. The structures were elucidated by spectroscopic methods, mainly NMR and mass spectrometry. Circular dichroism was used to determine their axial stereochemistry revealing 1 and 2 to be atropisomers. 1 and 2 inhibited [125I]sauvagine binding to corticotropin releasing hormone (CRH-1) receptors.


Asunto(s)
Hypericum/química , Plantas Medicinales , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Acetilación , Proteínas Anfibias , Unión Competitiva , Interacciones Farmacológicas , Espectroscopía de Resonancia Magnética , Conformación Molecular , Hormonas Peptídicas , Péptidos/farmacología , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Vasodilatadores/farmacología
10.
Int J Radiat Biol ; 68(2): 153-62, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7658140

RESUMEN

Radiation-induced DNA double-strand breaks (dsbs) were measured in CHO-K1 cells by means of an experimental approach involving constant-field gel electrophoresis and densitometric scanning of ethidium bromide stained gels. For X-irradiation, an induction efficiency of 36 +/- 5 dsbs (Gy x cell)-1 was determined. With this set-up, the induction of dsbs was investigated in CHO-K1 cells after irradiation with accelerated carbon ions with specific energies ranging from 2.7 to 261 MeV/u. This set of particle beams covers the important linear energy transfer (LET) range between 17 and 400 keV/microns, where maximum efficiencies have been reported for other cellular endpoints like inactivation or mutation induction. For LETs up to 100 keV/microns, RBEs of approximately 1 have been determined, while efficiencies per unit dose decline for higher LETs. No RBE maximum > 1 was found. Data are compared with published results on dsb induction in mammalian cells by radiations of comparable LET.


Asunto(s)
Carbono/química , Daño del ADN , Animales , Bacteriófago lambda , Células CHO , Cricetinae , ADN Viral/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Técnicas In Vitro , Iones , Transferencia Lineal de Energía , Rayos X
11.
Vet Parasitol ; 117(1-2): 51-60, 2003 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-14597279

RESUMEN

Forty-eight helminth-free lambs were divided into eight groups (A-H) of six animals. Groups A-G were infected artificially with 10,000 third stage larvae of Haemonchus contortus and 20,000 third stage larvae of Trichostrongylus colubriformis, whereas group H remained uninfected. Thirty days post-infection the lambs were treated orally with a single dosage of one of the following products: group A with 3 mg/kg body weight (BW) of an aqueous ethanol extract (70%, v/v) of the seeds of Azadirachta indica A. Juss syn. Melia azedarach L. (Meliaceae); group B with 1 g/kg BW of a raw powder of the leaves of Ananas comosus (L.) Merr. (Bromeliaceae); group C with 0.3 mg/kg BW of an aqueous ethanol extract of a 1:1 mixture (g/g) of Vernonia anthelmintica (L.) Willd. (Asteraceae) seeds and Embelia ribes Burm (Myrsinaceae) fruits; group D with 183 mg/kg BW of an aqueous ethanol extract of the whole plants of Fumaria parviflora Lam. (Fumariaceae); group E with 28 mg/kg BW of an aqueous ethanol extract of the seeds of Caesalpinia crista L. (Caesalpiniaceae); group F with 25 mg/kg BW of pyrantel tartrate and group G with 50% ethanol. Group H remained untreated. Only the ethanol extract of F. parviflora caused a strong reduction of the faecal egg counts (100%) and a 78.2 and 88.8% reduction of adult H. contortus and T. colubriformis on day 13 post-treatment. The extract was as effective as the reference compound pyrantel tartrate. Therefore, the ethanol extract itself or single constituents of F. parviflora could be a promising alternative source of anthelmintic for the treatment of gastrointestinal trichostrongylids in small ruminants.


Asunto(s)
Antihelmínticos/uso terapéutico , Hemoncosis/veterinaria , Fitoterapia , Extractos Vegetales/uso terapéutico , Enfermedades de las Ovejas/tratamiento farmacológico , Tricostrongiliasis/veterinaria , Administración Oral , Animales , Antihelmínticos/administración & dosificación , Heces/parasitología , Femenino , Hemoncosis/tratamiento farmacológico , Haemonchus/efectos de los fármacos , Haemonchus/crecimiento & desarrollo , Parasitosis Intestinales/tratamiento farmacológico , Parasitosis Intestinales/veterinaria , Masculino , Recuento de Huevos de Parásitos/veterinaria , Fitoterapia/veterinaria , Extractos Vegetales/administración & dosificación , Distribución Aleatoria , Ovinos , Tricostrongiliasis/tratamiento farmacológico , Trichostrongylus/efectos de los fármacos , Trichostrongylus/crecimiento & desarrollo
12.
Adv Space Res ; 18(1-2): 83-92, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-11538992

RESUMEN

DNA double-strand breaks (DSBs) are the crucial events ultimately leading to cell inactivation. Aimed at understanding the biological action of the charged particle component of cosmic radiation, the induction of DSBs and their repairability was evaluated in Chinese hamster ovary (CHO-K1) cells after exposure to accelerated particles. Irradiations were performed with various ion species including O, Ni and Ca, covering a LET range from 20 to 2000 keV/micrometer. DSBs were determined for plateau-phase cells using the electrophoretic elution of radiation-induced DNA fragments in a static electric field combined with fluorescence scanning of ethidium bromide stained gels. Assuming a DSB yield of 22 DSB per Gy per cell, as derived from X-irradiation, cross-sections for DSB production were calculated from the corresponding fluence-effect curves at a fraction of 0.7 of DNA retained. The same ordinate was used as a reference for the calculation of relative biological efficiency (RBE) for DSB induction. At low LETs (< or = 20 keV/micrometer) RBE values slightly above unity were obtained, but a decrease of RBE was observed with increasing LET. In the region of 100-200 keV/micrometer the RBE for initial DSB induction was clearly below unity. Rejoining of DSBs was assessed by measuring the fraction of DNA retained following post-irradiation incubation of cells under culture conditions. After exposure to Ca ions, DSB rejoining was considerably impaired compared to X-rays.


Asunto(s)
Células CHO/efectos de la radiación , Daño del ADN , ADN/efectos de la radiación , Iones , Transferencia Lineal de Energía , Animales , Células CHO/citología , Calcio , Radiación Cósmica , Cricetinae , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Níquel , Oxígeno , Aceleradores de Partículas , Efectividad Biológica Relativa , Rayos X
13.
Adv Space Res ; 31(6): 1583-91, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12971414

RESUMEN

The lens epithelium is the initiation site for the development of radiation induced cataracts. Radiation in the cortex and nucleus interacts with proteins, while in the epithelium, experimental results reveal mutagenic and cytotoxic effects. It is suggested that incorrectly repaired DNA damage may be lethal in terms of cellular reproduction and also may initiate the development of mutations or transformations in surviving cells. The occurrence of such genetically modified cells may lead to lens opacification. For a quantitative risk estimation for astronauts and space travelers it is necessary to know the relative biological effectiveness (RBE), because the spacial and temporal distribution of initial physical damage induced by cosmic radiation differ significantly from that of X-rays. RBEs for the induction of DNA strand breaks and the efficiency of repair of these breaks were measured in cultured diploid bovine lens epithelial cells exposed to different LET irradiation to either 300 kV X-rays or to heavy ions at the UNILAC accelerator at GSI. Accelerated ions from Z=8 (O) to Z=92 (U) were used. Strand breaks were measured by hydroxyapatite chromatography of alkaline unwound DNA (overall strand breaks). Results showed that DNA damage occurs as a function of dose, of kinetic energy and of LET. For particles having the same LET the severity of the DNA damage increases with dose. For a given particle dose, as the LET rises, the numbers of DNA strand breaks increase to a maximum and then reach a plateau or decrease. Repair kinetics depend on the fluence (irradiation dose). At any LET value, repair is much slower after heavy ion exposure than after X-irradiation. For ions with an LET of less than 10,000 keV micrometers-1 more than 90 percent of the strand breaks induced are repaired within 24 hours. At higher particle fluences, especially for low energetic particles with a very high local density of energy deposition within the particle track, a higher proportion of non-rejoined breaks is found, even after prolonged periods of incubation. At the highest LET value (16,300 keV micrometers-1) no significant repair is observed. These LET-dependencies are consistent with the current mechanistic model for radiation induced cataractogenesis which postulates that genomic damage to the surviving fraction of epithelial cells is responsible for lens opacification.


Asunto(s)
Catarata/etiología , Daño del ADN , Reparación del ADN , Células Epiteliales/efectos de la radiación , Cristalino/efectos de la radiación , Transferencia Lineal de Energía , Animales , Bovinos , Iones Pesados , Cristalino/citología , Aceleradores de Partículas , Efectividad Biológica Relativa , Medición de Riesgo , Rayos X
14.
Pharmazie ; 49(7): 509-11, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8073060

RESUMEN

In vivo skin penetration studies of the Camomile flavones apigenin, luteolin and apigenin 7-O-beta-glucoside were carried out with nine healthy, female volunteers. During seven hours the decline of flavonoid concentration in a saturated aqueous alcoholic solution filled in glass application chambers were repeatedly measured by spectrophotometry at fixed time periods. The maximal fluxes were calculated. From the graph of the maximal flux values as a function of time it was concluded, that the flavonoids are not only adsorbed at the skin surface, but penetrate into deeper skin layers. This is important for their topical use as antiphlogistic agents.


Asunto(s)
Apigenina , Flavonoides/farmacocinética , Plantas Medicinales/química , Absorción Cutánea , Administración Tópica , Manzanilla , Femenino , Flavonoides/administración & dosificación , Flavonoides/farmacología , Humanos , Luteolina , Aceites Volátiles/administración & dosificación , Aceites Volátiles/farmacocinética
15.
Rev Med Interne ; 10(4): 375-81, 1989.
Artículo en Francés | MEDLINE | ID: mdl-2552552

RESUMEN

This open, randomised multicenter trial compares the efficacy and safety of Fragmin administered subcutaneously twice daily with standard heparin administered by continuous infusion in the treatment of deep vein thrombosis (DVT). The initial dose of Fragmin is 100 U anti-Xa/kg/12 h and the further doses are adjusted according to the anti-Xa activity between 0.5 and 0.8 U/ml, 3 hours after the morning injection. The initial dose of standard heparin is 240 UI/kg/12 h. The dose adjustments are based on the daily results of APTT (1.5 - 3 times the control). Treatments efficacy are appreciated when comparing the venography performed before and after 10 days of treatment. The safety is evaluated on clinical parameters and iterative biological tests. Sixty-six patients have been included in this study. Efficacy of the two treatments is equivalent with a phlebographic improvement in respectively 79.3 p. 100 (Heparin Group) and 71.0 p. 100 (Fragmin Group) of the cases and an aggravation in 3.4 p. 100 and 6.4 p. 100 (NS) respectively. The frequency of dosage adjustments is lower and the stability of biological tests is better in the Fragmin group. In conclusion, the administration of Fragmin twice daily by subcutaneous route seems to be equivalent at least to standard heparin continuous infusion in the treatment of recent DVT. The better convenience and safety of Fragmin have to be verified on a larger panel of patients.


Asunto(s)
Heparina de Bajo-Peso-Molecular/uso terapéutico , Tromboflebitis/tratamiento farmacológico , Adulto , Anciano , Femenino , Heparina/administración & dosificación , Heparina/uso terapéutico , Heparina de Bajo-Peso-Molecular/administración & dosificación , Humanos , Infusiones Intravenosas , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Distribución Aleatoria
16.
Phytochemistry ; 90: 106-13, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23499166

RESUMEN

Rusci rhizoma extracts are traditionally used against chronic venous disorders (CVD). To determine the effect of its secondary plant metabolites on the endothelium, phenolic compounds and saponins from Butcher's broom were isolated from a methanolic extract, and their activity on the thrombin-induced hyperpermeability of human microvascular endothelial cells (HMEC-1) was investigated in vitro. In addition to the six known spirostanol saponins deglucoruscin (5), 22-O-methyl-deglucoruscoside (6), deglucoruscoside (7), ruscin (8), ruscogenin-1-O-(α-l-rhamnopyranosyl-(1→2)-ß-d-galactopyranoside (9) and 1-O-sulpho-ruscogenin (10), three new spirostanol derivatives were isolated and identified: 3'-O-acetyl-4'-O-sulphodeglucoruscin (1), 4'-O-(2-hydroxy-3-methylpentanoyl)-deglucoruscin (2) and 4'-O-acetyl-deglucoruscin (3). Furthermore, the coumarin esculin (4), which is also prominently present in other medicinal plants used in the treatment of CVD, was isolated for the first time from Rusci rhizoma. Five of the isolated steroid derivatives (2, 5, 8, 9 and 10) and esculin (4) were tested for their ability to reduce the thrombin-induced hyperpermeability of endothelial cells in vitro, and the results were compared to those of the aglycone neoruscogenin (11). The latter compound showed a slight but concentration-dependent reduction in hyperpermeability to 71.8% at 100µM. The highest activities were observed for the spirostanol saponins 5 and 8 and for esculin (4) at 10µM, and these compounds resulted in a reduction of the thrombin-induced hyperpermeability to 41.9%, 42.6% and 53.3%, respectively. For 2, 5 and 8, the highest concentration tested (100µM) resulted in a drastic increase of the thrombin effect. The effect of esculin observed at a concentration of 10µM was diminished at 100µM. These in vitro data provide insight into the pharmacological mechanism by which the genuine spirostanol saponins and esculin can contribute to the efficacy of Butcher's broom against chronic venous disorders.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Esculina/farmacología , Ruscus/química , Saponinas/farmacología , Espirostanos/farmacología , Trombina/antagonistas & inhibidores , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Esculina/química , Esculina/aislamiento & purificación , Humanos , Estructura Molecular , Permeabilidad/efectos de los fármacos , Saponinas/química , Saponinas/aislamiento & purificación , Espirostanos/química , Espirostanos/aislamiento & purificación , Relación Estructura-Actividad , Trombina/farmacología
17.
Phytomedicine ; 19(3-4): 245-52, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21982436

RESUMEN

INTRODUCTION: A quantified aqueous Willow bark extract (STW 33-I) was tested concerning its inhibitory activity on TNF-α induced ICAM-1 expression in human microvascular endothelial cells (HMEC-1) and further fractionated to isolate the active compounds. RESULTS: At 50 µg/ml the extract, which had been prepared from Salix purpurea L., decreased ICAM-1 expression to 40% compared to control cells without showing cytotoxic effects. Further liquid-liquid partition revealed an ethyl acetate phase with potent reduction of ICAM-1 expression to 40% at 8 µg/ml. This fraction was comprehensively characterised by the isolation of flavanone aglyca and their corresponding glycosides, chalcone glycosides, salicin derivatives, cyclohexane-1,2-diol glycosides, catechol and trans-p-coumaric acid. All compounds were investigated for their activity on TNF-α induced ICAM-1 expression. The flavonoid and chalcone glycosides were not active up to 50 µM, whereas catechol and eriodictyol at the same concentration showed a significant reduction of ICAM-1 expression to 50% of control. Interestingly, other isolated flavanone aglyca like taxifolin, dihydrokaempferol and naringenin showed only weak or moderate inhibitory activity. Eriodictyol was a minor compound in the extract, whereas the catechol content in the extract (without excipients) reached 2.3%, determined by HPLC. One of the isolated cyclohexan-1,2-diol glucosides, 6'-O-4-hydroxybenzoyl-grandidentin, is a new natural compound. CONCLUSION: As catechol is quantitatively important in Willow bark extracts it can be concluded from the in vitro data that not only flavonoids and salicin derivatives, but also catechol can probably contribute to the anti-inflammatory activity of Willow bark extracts.


Asunto(s)
Catecoles/farmacología , Células Endoteliales/efectos de los fármacos , Flavonoides/farmacología , Molécula 1 de Adhesión Intercelular/metabolismo , Corteza de la Planta/química , Extractos Vegetales/farmacología , Acetatos/química , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Supervivencia Celular , Fraccionamiento Químico/instrumentación , Fraccionamiento Químico/métodos , Cromatografía Líquida de Alta Presión , Ácidos Cumáricos/química , Células Endoteliales/metabolismo , Flavanonas/farmacología , Humanos , Estructura Molecular , Extractos Vegetales/química , Quercetina/análogos & derivados , Quercetina/farmacología , Salix/química , Factor de Necrosis Tumoral alfa/efectos adversos
18.
Phytomedicine ; 19(3-4): 322-9, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22119042

RESUMEN

BACKGROUND AND OBJECTIVE: Gene expression profiles of Sprague-Dawley (SD) rats treated with a standardized willow bark extract (WB), its salicin rich ethanol fraction (EtOH-FR) or the tricyclic antidepressant imipramine were evaluated for their potential to induce adverse events. Treatments had shown antidepressant-like effects. METHODS: Gene expression profiles (Agilent Whole Genome Array, n=4/group) obtained from the peripheral blood of male SD rats treated with WB (STW 33-I), EtOH-FR (30 mg/kg bw) or imipramine (20 mg/kg bw) were analysed comparatively by the Ingenuity Systems Programme, which allows to conduct model calculations of thresholds for theoretical potential adverse events (AE). RESULTS: The number of genes regulated by the three treatments were 1673 (WB), 117 (EtOH-FR) and 1733 (imipramine). The three treatments related to 47 disease clusters. The WB extract reached the threshold for a potential AE in one disease cluster (cardiac hypertrophy), whereas the EtOH-FR exceeded the threshold in 5 disease clusters (cardiac arteriopathy and stenosis, glomerular injury, pulmonary hypertension, alkaline phosphatase levels ⇑). Imipramine treatment hit 13 disease clusters: tachycardia, palpitation, myocardial infarction, arrhythmias, heart block, precipitation of congestive heart failure; urinary retention, altered liver functions. Those correspond to known potential adverse events. Glomerular injury and altered liver functions are part of the side effect profile of salicylic acid derivatives in agreement with the findings for the salicin rich EtOH-FR. CONCLUSION: There is no linear relationship between the number of constituents of a drug (preparation) and the number of different targets hit in a biological system on the gene expression level. Therefore, the number of genetic targets in a biological system does not necessarily increase with the complexity of the treatment corresponding to the non-linear behaviour of biological systems. Regarding gene expression levels AE of single treatments are not necessarily additive in combination treatments. The applied method appears to be an interesting screening tool for the prediction of potential AE. The phenomena that imipramine crossed the potential threshold for AEs several times whereas the WB extract did reach the threshold level only once, however not backed by clinical data for this AE, deserves to be further investigated. It questions the commonly assumed principle that substances with low number or without AE will have a poor efficacy.


Asunto(s)
Antidepresivos Tricíclicos/efectos adversos , Perfilación de la Expresión Génica/métodos , Cardiopatías/inducido químicamente , Imipramina/efectos adversos , Salicilatos/efectos adversos , Animales , Antidepresivos Tricíclicos/química , Alcoholes Bencílicos/efectos adversos , Alcoholes Bencílicos/química , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Etanol/química , Regulación de la Expresión Génica/efectos de los fármacos , Glucósidos/efectos adversos , Glucósidos/química , Cardiopatías/tratamiento farmacológico , Cardiopatías/patología , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/patología , Imipramina/química , Masculino , Nefritis/inducido químicamente , Nefritis/patología , Fitoterapia/efectos adversos , Corteza de la Planta/efectos adversos , Corteza de la Planta/química , Extractos Vegetales/efectos adversos , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley , Salicilatos/química
19.
Phytomedicine ; 19(10): 930-9, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22743246

RESUMEN

Inflammatory processes are increasingly recognised to contribute to neurological and neuropsychatric disorders such as depression. Thus we investigated whether a standardized willow bark preparation (WB) which contains among other constituents salicin, the forerunner of non-steroidal antiphlogistic drugs, would have an effect in a standard model of depression, the forced swimming test (FST), compared to the antidepressant imipramine. Studies were accompanied by gene expression analyses. In order to allocate potential effects to the different constituents of WB, fractions of the extract with different compositions of salicyl alcohol derivative and polyphenols were also investigated. Male Sprague Dawley rats (n=12/group) were treated for 14 days (p.o.) with the WB preparation STW 33-I (group A) and its fractions (FR) (groups FR-B to E) in concentrations of 30 mg/kg. The FRs were characterized by a high content of flavone and chalcone glycosides (FR-B), flavonoid glycosides and salicyl alcohol derivatives (FR-C), salicin and related salicyl alcohol derivatives (FR-D) and proanthocyanidines (FR-E). The tricyclic antidepressant imipramine (20 mg/kg) (F) was used as positive control. The FST was performed on day 15. The cumulative immobility time was significantly (p<0.05) reduced in group A (36%), group FR-D (44%) and by imipramine (16%) compared to untreated controls. RNA was isolated from peripheral blood. RNA samples (group A, group FR-D, and imipramine) were further analysed by rat whole genome microarray (Agilent) in comparison to untreated controls. Quantitative PCR for selected genes was performed. Genes (>2 fold, p<0.01), affected by WB and/or FR-D and imipramine, included both inflammatory (e.g. IL-3, IL-10) and neurologically relevant targets. Common genes regulated by WB, FR-D and imipramine were GRIA 2 ↓, SRP54 ↓, CYP26B ↓, DNM1L ↑ and KITLG ↓. In addition, the hippocampus of rats treated (27 d) with WB (15-60 mg/kg WB) or imipramine (15 mg/kg bw) showed a slower serotonin turnover (5-hydroxyindol acetic acid/serotonin (p<0.05)) depending on the dosage. Thus WB (30 mg/kg), its ethanolic fraction rich in salicyl alcohol derivatives (FR-D) (30 mg/kg) and imipramine, by being effective in the FST, modulated known and new targets relevant for neuro- and immunofunctions in rats. These findings contribute to our understanding of the link between inflammation and neurological functions and may also support the scope for the development of co-medications from salicylate-containing phytopharmaceuticals as multicomponent mixtures with single component synthetic drugs.


Asunto(s)
Antidepresivos/farmacología , Encéfalo/efectos de los fármacos , Depresión , Imipramina/farmacología , Inflamación , Ácido Salicílico/farmacología , Salix/química , Animales , Antidepresivos/uso terapéutico , Antidepresivos Tricíclicos/farmacología , Antidepresivos Tricíclicos/uso terapéutico , Alcoholes Bencílicos/análisis , Alcoholes Bencílicos/farmacología , Alcoholes Bencílicos/uso terapéutico , Encéfalo/inmunología , Encéfalo/metabolismo , Citocinas/sangre , Depresión/tratamiento farmacológico , Depresión/inmunología , Depresión/metabolismo , Sistemas de Liberación de Medicamentos , Flavonoides/análisis , Flavonoides/farmacología , Flavonoides/uso terapéutico , Expresión Génica , Glucósidos/farmacología , Glucósidos/uso terapéutico , Imipramina/uso terapéutico , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/metabolismo , Masculino , Análisis por Micromatrices , Fitoterapia , Corteza de la Planta , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley , Ácido Salicílico/uso terapéutico , Serotonina/metabolismo , Natación
20.
Phytomedicine ; 17(1): 19-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19897346

RESUMEN

Among the many known health benefits of tea catechins count anti-inflammatory and neuroprotective activities, as well as effects on the regulation of food intake. Here we address cannabimimetic bioactivity of catechin derivatives occurring in tea leaves as a possible cellular effector of these functionalities. Competitive radioligand binding assays using recombinant human cannabinoid receptors expressed in Chem-1 and CHO cells identified (-)-epigallocatechin-3-O-gallate, EGCG (K(i)=33.6 microM), (-)-epigallocatechin, EGC (K(i)=35.7 microM), and (-)-epicatechin-3-O-gallate, ECG (K(i)=47.3 microM) as ligands with moderate affinity for type 1 cannabinoid receptors, CB1. Binding to CB2 was weaker with inhibition constants exceeding 50 microM for EGC and ECG. The epimers (+)-catechin and (-)-epicatechin exhibited negligible affinities for both CB1 and CB2. It can be concluded that central nervous cannabinoid receptors may be targeted by selected tea catechins but signaling via peripheral type receptors is less likely to play a major role in vivo.


Asunto(s)
Camellia sinensis/química , Cannabinoides/metabolismo , Catequina/metabolismo , Extractos Vegetales/metabolismo , Receptores de Cannabinoides/metabolismo , Catequina/análogos & derivados , Catequina/química , Línea Celular , Humanos , Ligandos , Hojas de la Planta , Proteínas Recombinantes , Transducción de Señal ,
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