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1.
Anaesthesia ; 77(2): 164-174, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34555189

RESUMEN

The association between intra-operative hypotension and postoperative acute kidney injury, mortality and length of stay has not been comprehensively evaluated in a large single-centre hip fracture population. We analysed electronic anaesthesia records of 1063 patients undergoing unilateral hip fracture surgery, collected from 2015 to 2018. Acute kidney injury, 3-, 30- and 365-day mortality and length of stay were evaluated to assess the relationship between intra-operative hypotension absolute values (≤ 55, 60, 65, 70 and 75 mmHg) and duration of hypotension. The rate of acute kidney injury was 23.7%, mortality at 3-, 30- and 365 days was 3.7%, 8.0% and 25.3%, respectively, and median (IQR [range]) length of stay 8 (6-12 [0-99]) days. Median (IQR [range]) time ≤ MAP 55, 60, 65, 70 and 75 mmHg was 0 (0-0.5[0-72.1]); 0 (0-4.4 [0-104.9]); 2.2 (0-8.7 [0-144.2]); 6.6 (2.2-19.7 [0-198.8]); 17.5 (6.6-37.1 [0-216.3]) minutes, and percentage of surgery time below these thresholds was 1%, 2.5%, 7.9%, 12% and 21% respectively. There were some univariate associations between hypotension and mortality; however, these were no longer evident in multivariable analysis. Multivariable analysis found no association between hypotension and acute kidney injury. Acute kidney injury was associated with male sex, antihypertensive medications and cardiac/renal comorbidities. Three-day mortality was associated with delay to surgery ? 48 hours, whilst 30-day and 365-day mortality was associated with delay to surgery ≥ 48 hours, impaired cognition and cardiac/renal comorbidities. While the rate of acute kidney injury was similar to other studies, use of vasopressors and fluids to reduce the time spent at hypotensive levels failed to reduce this complication. Intra-operative hypotension at the levels observed in this cohort may not be an important determinant of acute kidney injury, postoperative mortality and length of stay.


Asunto(s)
Lesión Renal Aguda/mortalidad , Tratamiento de Urgencia/mortalidad , Fracturas de Cadera/mortalidad , Hipotensión/mortalidad , Complicaciones Intraoperatorias/mortalidad , Complicaciones Posoperatorias/mortalidad , Lesión Renal Aguda/diagnóstico , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Tratamiento de Urgencia/tendencias , Femenino , Fracturas de Cadera/cirugía , Humanos , Hipotensión/diagnóstico , Complicaciones Intraoperatorias/diagnóstico , Tiempo de Internación/tendencias , Masculino , Monitoreo Intraoperatorio/mortalidad , Monitoreo Intraoperatorio/tendencias , Mortalidad/tendencias , Complicaciones Posoperatorias/diagnóstico , Estudios Prospectivos , Estudios Retrospectivos
3.
Appl Microbiol Biotechnol ; 103(17): 7161-7175, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31352507

RESUMEN

The explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a contaminant at many military sites. RDX bioremediation as a clean-up approach has been gaining popularity because of cost benefits compared to other methods. RDX biodegradation has primarily been linked to six functional genes (diaA, nfsI, pnrB, xenA, xenB, xplA). However, current methods for gene quantification have the risk of false negative results because of low theoretical primer coverage. To address this, the current study designed new primer sets using the EcoFunPrimer tool based on sequences collected by the Functional Gene Pipeline and Repository and these were verified based on residues and motifs. The primers were also designed to be compatible with the SmartChip Real-Time PCR system, a massively parallel singleplex PCR platform (high throughput qPCR), that enables quantitative gene analysis using 5,184 simultaneous reactions on a single chip with low volumes of reagents. This allows multiple genes and/or multiple primer sets for a single gene to be used with multiple samples. Following primer design, the six genes were quantified in RDX-contaminated groundwater (before and after biostimulation), RDX-contaminated sediment, and uncontaminated samples. The final 49 newly designed primer sets improved upon the theoretical coverage of published primer sets, and this corresponded to more detections in the environmental samples. All genes, except diaA, were detected in the environmental samples, with xenA and xenB being the most predominant. In the sediment samples, nfsI was the only gene detected. The new approach provides a more comprehensive tool for understanding RDX biodegradation potential at contaminated sites.


Asunto(s)
Proteínas Bacterianas/genética , Contaminantes Ambientales/metabolismo , Sustancias Explosivas/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Triazinas/metabolismo , Proteínas Bacterianas/química , Biodegradación Ambiental , Cartilla de ADN/genética , Sedimentos Geológicos/microbiología , Agua Subterránea/microbiología
5.
Cerebrovasc Dis ; 28(4): 378-83, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19641313

RESUMEN

BACKGROUND: Interventions that may reduce the number and severity of potentially harmful post-stroke complications are desirable. This study explored whether very early and frequent mobilisation (VEM) affected complication type (immobility/stroke related), number and severity. METHODS: Secondary analysis from phase II, randomised controlled trial. Patients admitted within 24 h of stroke, whose physiological parameters fell within set limits, were randomised to either VEM, commencing <24 h, or standard care. Complications to 3 months were recorded by a blinded assessor and classified by a neurologist. Analysis was intention to treat. RESULTS: Seventy-one patients were recruited (standard care 33; VEM 38).There were no significant group differences in the number, type or severity of complications by 3 months, and most patients (81.6%) experienced one or more complications. Falls were common, while depression was absent. The multivariate analysis showed older age (OR 1.10, 95% CI: 1.02-1.18, p = 0.009) and longer length of stay (OR 1.18, 95% CI: 1.06-1.32, p = 0.002) were associated with experiencing an immobility-related complication. CONCLUSION: Interventions that promote recovery and reduce complications may consequently reduce length of stay. The larger phase III trial currently underway may shed light on whether increasing mobilisation reduces complications after stroke.


Asunto(s)
Reposo en Cama/efectos adversos , Ambulación Precoz , Rehabilitación de Accidente Cerebrovascular , Accidentes por Caídas/prevención & control , Factores de Edad , Anciano , Anciano de 80 o más Años , Depresión/etiología , Depresión/prevención & control , Femenino , Humanos , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Recurrencia , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Método Simple Ciego , Fumar/efectos adversos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/psicología , Factores de Tiempo , Resultado del Tratamiento , Infecciones Urinarias/etiología , Infecciones Urinarias/prevención & control , Victoria/epidemiología
6.
Dev Biol ; 234(1): 204-15, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11356030

RESUMEN

In the developing heart, the epicardium is essential for coronary vasculogenesis as it provides precursor cells that become coronary vascular smooth muscle and perivascular fibroblasts. These precursor cells are derived from the epicardium via epithelial-mesenchymal transformation (EMT). The factors that regulate epicardial EMT are unknown. Using a quantitative in vitro collagen gel assay, we show that serum, FGF-1, -2, and -7, VEGF, and EGF stimulate epicardial EMT. TGFbeta-1 stimulates EMT only weakly, while TGFbeta-2 and -3 do not stimulate EMT. TGFbeta-1, -2, or -3 strongly inhibits transformation of epicardial cells stimulated with FGF-2 or heart-conditioned medium. TGFbeta-3 does not block expression of vimentin, a mesenchymal marker, but appears to inhibit EMT by blocking epithelial cell dissociation and subsequent extracellular matrix invasion. Blocking antisera directed against FGF-1, -2, or -7 substantially inhibit conditioned medium-stimulated EMT in vitro, while antibodies to TGFbeta-1, -2, or -3 increase it. We confirmed FGF stimulation and TGFbeta inhibition of epicardial EMT in organ culture. Immunoblot analysis confirmed the presence of FGF-1, -2, and -7 and TGFbeta-1, -2, and -3 in conditioned medium, and we localized these growth factors to the myocardium and epicardium of stage-appropriate embryos by immunofluorescence. Our results strongly support a model in which myocardially derived FGF-1, -2, or -7 promotes epicardial EMT, while TGFbeta-1, -2, or -3 restrains it. Epicardial EMT appears to be regulated through a different signaling pathway than endocardial EMT.


Asunto(s)
Vasos Coronarios/embriología , Factores de Crecimiento de Fibroblastos/farmacología , Corazón/embriología , Mesodermo/citología , Pericardio/embriología , Animales , Comunicación Celular , Embrión de Pollo , Técnicas In Vitro , Queratinas/biosíntesis , Modelos Biológicos , Pericardio/citología , Factor de Crecimiento Transformador beta/farmacología , Vimentina/biosíntesis
7.
J Lab Clin Med ; 131(5): 432-41, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9605108

RESUMEN

Cross-linked hemoglobin (alphaalpha-Hb) may be a useful red blood cell substitute if it can be administered safely. However, cell-free hemoglobin has inherent properties that may cause oxidant-mediated toxicity. We investigated whether alphaalpha-Hb induces oxidative or inflammatory responses that lead to liver damage. alphaalpha-Hb (0.5 or 1.0 gm/kg) was infused into rats, and indices of liver injury, inflammation, and oxidative stress were examined. Although focal hepatic necrosis was noted at 24 hours, plasma alanine aminotransferase activity was not increased and lesions were resolved by 48 hours. Modest neutrophil accumulation in hepatic vessels, but not sinusoids, occurred at 24 hours. Heme oxygenase-1 (HO-1) protein and activity were induced in a dose- and time-dependent manner, with maximal induction at 24 hours. Plasma tumor necrosis factor-alpha levels were not significantly increased. Additional cytokine- and oxidant-mediated events such as nuclear transcription factor-kappaB activation and nitric oxide synthase induction were not observed. These results suggest that alphaalpha-Hb-derived products such as heme and ferric iron (Fe3+), potent inducers of HO-1, are responsible for increasing HO-1. HO-1 induction may be a protective response by the liver to metabolize excess heme and Fe3+, thereby providing antioxidative products to counter the potentially damaging oxidants produced by Fe3+-catalyzed reactions.


Asunto(s)
Aspirina/análogos & derivados , Hemoglobinas , Hepatitis Animal/inducido químicamente , Animales , Inducción Enzimática/fisiología , Hemo Oxigenasa (Desciclizante)/metabolismo , Hemo-Oxigenasa 1 , Hepatitis Animal/enzimología , Hepatitis Animal/patología , Mediadores de Inflamación/metabolismo , Infusiones Intravenosas , Hígado/metabolismo , Hígado/patología , Masculino , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Estrés Oxidativo/fisiología , Ratas , Ratas Sprague-Dawley
8.
Int J Radiat Oncol Biol Phys ; 38(2): 257-61, 1997 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-9226311

RESUMEN

PURPOSE: High-linear energy transfer (LET) radiation beams have potential applications in the treatment of glioblastoma, but have not yet demonstrated significant improvement in results. However, some patients have had local control of glioblastoma with high-LET irradiations such as neutrons and heavy charged particles. METHODS AND MATERIALS: In this collaborative study, 15 patients were entered into a randomized protocol comparing two dose levels of 20 and 25 Gy in 4 weeks of neon ion irradiation. This trial was intended to determine the optimal neon dose in terms of survival and effects of radiation. RESULTS: Fourteen patients were evaluable with no significant differences in median survival (13 and 14 months; p = NS) or median time to failure (7 and 9 months; p = NS) between the two dose arms. Three patients died of nontumor-related causes, of whom one (who died 19 months posttreatment) had autopsy confirmation of no tumor on pathological exam. The other two patients had stable magnetic resonance imaging scans at 6 and 22 months posttreatment. CONCLUSION: Although the results did not demonstrate the optimal high-LET dose level, there is an intriguing effect in that two patients had control of glioblastoma until death at 19 and 22 months. This suggests that better conformation of the high-LET dose to the tumor with neutron capture therapy or dynamic conformal heavy charged particle therapy might control glioblastoma while minimizing brain damage from radiation.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Transferencia Lineal de Energía , Neón/uso terapéutico , Adulto , Anciano , Neoplasias Encefálicas/mortalidad , Causas de Muerte , Femenino , Glioblastoma/mortalidad , Humanos , Masculino , Persona de Mediana Edad
9.
Am J Physiol ; 272(2 Pt 1): G207-14, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9124343

RESUMEN

Regulation of induced nitric oxide synthase (NOS) in isolated rat hepatocytes is poorly understood. The specific protein tyrosine kinase inhibitor genistein was used to determine if NOS induction is dependent on protein tyrosine kinase activation. Genistein inhibited tumor necrosis factor-alpha (TNF-alpha)-stimulated induction of NOS activity and NOS protein in a dose-dependent manner. Genistein also impaired TNF-alpha-induced NOS mRNA accumulation, suggesting protein tyrosine kinase regulation of NOS induction occurred at the level of transcription-translation. Like TNF-alpha, genistein inhibited induction of NOS protein by a second proinflammatory cytokine, interleukin-1beta, suggesting similar activation mechanisms by proinflammatory cytokines. NOS induction by other stimuli, including phorbol 12-myristate 13-acetate and the superoxide-generating system xanthine/xanthine oxidase, was also inhibited by genistein. Finally, cytokine-stimulated protein tyrosine kinase activity in hepatocytes was demonstrated by increased tyrosine phosphorylation of five high molecular mass protein bands. Genistein inhibited this cytokine-induced phosphotyrosine increase. The commonality of genistein inhibition suggests that protein tyrosine kinase activity is critical for NOS induction by a variety of stimuli.


Asunto(s)
Hígado/enzimología , Óxido Nítrico Sintasa/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Animales , Células Cultivadas , Inducción Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Genisteína , Interleucina-1/farmacología , Isoflavonas/farmacología , Hígado/citología , Masculino , Óxido Nítrico Sintasa/antagonistas & inhibidores , Fosfotirosina/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Acetato de Tetradecanoilforbol/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Xantina , Xantina Oxidasa/farmacología , Xantinas/farmacología
10.
Fundam Appl Toxicol ; 25(1): 60-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7601328

RESUMEN

A mouse model was used to identify potential biomarkers of exposure to the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Female C57B1/6 mice were treated weekly with 0.2 microgram TCDD/kg body weight or vehicle for 14-15 months. Phenotypic analysis by flow cytometry identified the major cell subpopulations in the spleen, thymus, and peripheral blood as defined by the expression of CD4, CD8, B220, and Mac-1 molecules. These subpopulations were further characterized for the expression of I-A, Pgp-1, CD45RB, and/or T cell receptor antigens (CD3, alpha beta, gamma delta). A group of young (4 months old) mice was evaluated concurrently to document immunophenotype alterations associated with aging. Results showed several age-related changes in phenotype distribution in the spleen and blood, but not in the thymus, despite significant age-dependent thymic involution. The age-dependent changes in splenic phenotypes included a decreased frequency of CD4+ cells and a major shift in the frequency distribution from naive T cells to effector and memory T cells as defined by Pgp-1 and CD45RB expression. These phenotypic changes in the spleen due to aging correlated with similar changes in the blood, providing preliminary support for the use of spleen cells as surrogates for blood in the development of biomarkers of immunotoxicity. In comparison to the effects of aging, TCDD treatment produced relatively subtle changes in immunophenotypes.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Linfocitos/efectos de los fármacos , Dibenzodioxinas Policloradas/toxicidad , Bazo/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Timo/efectos de los fármacos , Envejecimiento , Animales , Antígenos CD/análisis , Femenino , Citometría de Flujo , Inmunofenotipificación , Ratones , Ratones Endogámicos C57BL , Dibenzodioxinas Policloradas/inmunología , Receptores de Antígenos/análisis , Bazo/citología , Bazo/inmunología , Timo/citología , Timo/inmunología
11.
Adv Space Res ; 14(10): 501-5, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11539986

RESUMEN

Retrospective and ongoing analyses of clinical records from 347 primary intraocular melanoma patients treated with helium ions at LBL will allow examination of the exposure-response data for human cataract; which is a complication of the therapy from incidental exposure of the lens. Direct particle beam traversal of at least a portion of the lens usually is unavoidable in treatment of posterior intraocular tumors. The precise treatment planned for each patient permits quantitative assessment of the lenticular dose and its radiation quality. We are reporting our preliminary results on the development of helium-ion-induced lens opacifications and cataracts in 54 of these patients who had 10% or less of their lens in the treatment field. We believe these studies will be relevant to estimating the human risk for cataract in space flight.


Asunto(s)
Catarata/etiología , Helio/efectos adversos , Cristalino/efectos de la radiación , Melanoma/radioterapia , Neoplasias de la Úvea/radioterapia , Adulto , Medicina Aeroespacial , Anciano , Estudios de Seguimiento , Humanos , Iones , Persona de Mediana Edad , Aceleradores de Partículas , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Medición de Riesgo
12.
Int J Radiat Oncol Biol Phys ; 29(4): 647-55, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8040010

RESUMEN

PURPOSE: To review the experience at University of California Lawrence Berkeley Laboratory in using charged particles to irradiate primary neoplasms of the skull base and those extending to the skull base from the nasopharynx and paranasal sinuses. METHODS AND MATERIALS: During the period from 1977 to 1992, 223 patients were irradiated with charged particles at the Lawrence Berkeley Laboratory for tumors either arising in or extending to the skull base, of whom 48 (22%) had recurrent lesions, either post previous surgery or radiotherapy. One hundred twenty-six patients had lesions arising in the cranial base, mostly chordoma (53), chondrosarcoma (27), paraclival meningioma (27) with 19 patients having other histologies such as osteosarcoma or neurofibrosarcoma. There were also 31 patients with primary or recurrent squamous carcinoma of the nasopharynx extending to the skull base, 44 patients with major or minor salivary gland tumors, mostly adenocarcinoma, and 22 patients with squamous carcinoma of the paranasal sinuses, all with cranial base extension. RESULTS: Local control and survival appeared improved in tumors arising in the skull base, following the ability with charged particles to deliver high doses (mean of 65 Gy-equivalent) with relative sparing of the adjacent normal tissues. The Kaplan-Meier 5-year local control was 85% for meningioma, 78% for chondrosarcoma, 63% for chordoma and 58% for other sarcoma. Follow-up ranged from 4-191 months with a median of 51 months. CONCLUSION: Charged particle radiotherapy is highly effective in controlling cranial base lesions which have have been partially resected. Better tumor localization with CT and MRI, improved 3-D treatment planning and beam delivery techniques have continued to reduce the level of serious complications and increase local control and survival.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias Craneales/radioterapia , Femenino , Helio , Humanos , Iones , Masculino , Neón , Radioterapia de Alta Energía
13.
Med Phys ; 20(5): 1387-98, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8289721

RESUMEN

The clinical usefulness of variable-modulation dose delivery of neon ion and proton beams over fixed-modulation beams is evaluated for several patients with tumors in the gastrointestinal tract by comparing dose distributions, dose volume histograms, and predictions of normal tissue complication probabilities calculated with the two methods. Both techniques provide excellent coverage of the target volume with neon ion and proton beams. The advantage of variable modulation is that less dose is delivered proximal to the target volume. For tumors in the gastrointestinal tract, this implies that less dose is given to the liver, gut, kidneys, and lungs. For the ten patients considered in this study, variable-modulation reduced the total integral dose by an average of 17% for neon ion beams and by 18% for protons as compared to fixed-modulation. If the tumor volume is excluded, the reduction in the integral dose to normal tissues ranged from 15% to 32% for neon ions and from 18% to 34% for proton beams. These gains are larger than those anticipated on the basis of an analytic study by Goitein and Chen [Med. Phys. 10, 831-840 (1983)], which predicted integral dose reductions of the order of 10% for protons and 14% for neon ions. They are also larger than those reported in a similar study by Urie and Goitein [Med. Phys. 16, 593-601 (1989)] for proton irradiation of skull-base tumors. This is probably because the tumors in the GI tract considered in this study were more irregularly shaped than Goitein and Chen's analytic model assumes. The results of this study also suggest that due to increased sparing of normal tissues, the number of different portal directions required to achieve a satisfactory treatment plan will be reduced for variable-modulation beam delivery systems. This implies that variable-modulation treatment plans will be easier to execute than current fixed-modulation plans.


Asunto(s)
Neoplasias Gastrointestinales/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Adenocarcinoma/radioterapia , Neoplasias del Sistema Biliar/radioterapia , Fenómenos Biofísicos , Biofisica , Neoplasias Esofágicas/radioterapia , Estudios de Evaluación como Asunto , Neoplasias Gastrointestinales/patología , Humanos , Iones , Modelos Estructurales , Neón , Neoplasias Pancreáticas/radioterapia , Protones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Radioterapia de Alta Energía
14.
Teratology ; 47(4): 275-80, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8322221

RESUMEN

Ellagic acid (EA) is a naturally occurring plant phenol that was recently demonstrated to protect cultured rat embryos from the embryotoxic effects of N-methyl-N-nitrosourea (MNU). The teratogenic mechanism of action of MNU, as well as other methylating agents, is debated: both cell death and mutation have been proposed. In some model systems, EA has been reported to selectively decrease the mutagenic DNA adduct O6-methylguanine (O6MG) when compared to the cytotoxic DNA adduct N7-methylguanine (N7MG). The present study was initiated to determine 1) the distribution of 14C-EA and 3H-MNU in the rat whole embryo culture model system and 2) the effects of EA on MNU-induced DNA adduct formation in this model system. 14C-EA (50 microM for 2 hr, known embryoprotective concentration; no MNU added) was used to demonstrate access of EA to the embryo within the 2 hr exposure period. The majority of EA (99.5%) remained in the media while tissue concentrations of 57.0 and 47.9 pmol/mg were attained in the yolk sacs and embryos, respectively. Similarly, MNU (75 microM for 1 hr, known effective concentration; no EA added) was distributed between the media, yolk sacs, and embryos at 99.7%, 73.7 and 112.9 pmol/mg, respectively. When non-radiolabeled EA (50 microM for 2 hr) was used to protect embryos prior to exposure to 3H-MNU (75 microM for 1 hr), the distribution of MNU in the model system was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anomalías Inducidas por Medicamentos/prevención & control , Daño del ADN , Ácido Elágico/uso terapéutico , Embrión de Mamíferos/efectos de los fármacos , Metilnitrosourea/toxicidad , Teratógenos/toxicidad , Animales , Ácido Elágico/farmacocinética , Embrión de Mamíferos/química , Guanina/análogos & derivados , Guanina/análisis , Metilnitrosourea/farmacocinética , Técnicas de Cultivo de Órganos , Ratas , Ratas Sprague-Dawley/embriología , Solubilidad , Teratógenos/farmacocinética , Saco Vitelino/química
15.
Teratology ; 46(2): 109-15, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1440415

RESUMEN

Ellagic acid is a naturally occurring plant phenol that has demonstrated anticarcinogenic and antimutagenic activity in several test systems. Given the common proposed etiopathogenic processes of mutagenesis, carcinogenesis, and teratogenesis induced by genotoxic chemicals, the present study was initiated to determine whether ellagic acid would protect rat embryos in culture from the teratogenic effects of N-methyl-N-nitrosourea (MNU). Ellagic acid alone (as used in these experiments; 50 microM in DMSO) was not embryotoxic. Ellagic acid (50 microM) significantly (P less than 0.01) prevented MNU (75 microM)-induced effects including mortality (absence of heart beat), abnormal formation of the cephalic neural tube derivatives, and delayed differentiation as assessed by a morphological scoring system. These embryoprotective effects were dose responsive. Sequential treatment of embryos with ellagic acid followed by MNU in fresh media also was embryoprotective with no diminution of effect. The site at which ellagic acid interrupts the critical teratogenic events induced by MNU is apparently within the embryo and/or placenta. This model of chemical embryoprotection may be useful in determining the role of cell death and/or mutation in the teratogenic mechanism of action of methylating agents.


Asunto(s)
Ectogénesis/efectos de los fármacos , Ácido Elágico/farmacología , Metilnitrosourea/toxicidad , Anomalías Inducidas por Medicamentos/prevención & control , Animales , Relación Dosis-Respuesta a Droga , Ratas , Ratas Sprague-Dawley/embriología , Teratógenos/farmacología
16.
Carcinogenesis ; 13(3): 509-12, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1547544

RESUMEN

N-Methyl-N-nitrosourea (MNU) induces thymic lymphosarcoma in numerous mouse strains. We determined the neoplastic phenotype induced by MNU in 20 C57B1/6J mice. Eleven neoplasms were composed of cells that were CD4-CD8+, four neoplasms were composed of cells that were CD4+CD8+, two neoplasms were mixtures of CD4+CD8+ and CD4-CD8+ cells, and three neoplasms were made up of cells that expressed neither CD4 nor CD8. Expanded populations of CD4+CD8- cells were observed within individual neoplasms. Of 10 neoplasms that were further classified, all were composed of cells that were J11d+, indicating immaturity. CD3 expression was generally negative, while IL2R expression was variable in these neoplasms. These data from C57B1/6J mice, a strain with a low incidence of spontaneous (viral-associated) thymic lymphosarcoma, indicate that a continuous spectrum of immature phenotypes are produced by MNU. The finding that each immature cell population can be expanded in this model system differs from previous reports. Our data do confirm the general finding in AKR mice, a strain with a high incidence of spontaneous thymic lymphosarcoma, that cells with immature phenotypes, particularly CD4-CD8+J11d+, make up MNU-induced thymic lymphosarcomas.


Asunto(s)
Antígenos CD , Linfoma no Hodgkin/patología , Glicoproteínas de Membrana , Neoplasias del Timo/patología , Animales , Antígenos de Diferenciación/análisis , Antígeno CD24 , Antígenos CD4/análisis , Antígenos CD8/análisis , Citometría de Flujo , Linfoma no Hodgkin/inducido químicamente , Metilnitrosourea , Ratones , Ratones Endogámicos AKR , Ratones Endogámicos C57BL , Fenotipo , Neoplasias del Timo/inducido químicamente
17.
Int J Radiat Oncol Biol Phys ; 24(4): 755-9, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1429101

RESUMEN

Between 1979 and 1989, 17 patients with unfavorable bone sarcoma were treated wholly or in part with heavy charged particle irradiation (helium and/or neon ions) at the University of California Lawrence Berkeley Laboratory. The majority of tumors were located near critical structures such as the spinal cord or brain. Gross tumor was present in all but two patients at the time of irradiation. Six patients were treated for recurrent disease. Histologies included osteosarcoma, Ewing's sarcoma, and recurrent osteoblastoma. Four of the osteosarcomata were believed to have been induced by previous therapeutic irradiation for various tumors. Follow-up time since initiation of radiation ranged from 7 to 118 months (median 40 months). The 5-year Kaplan-Maier local control rate was 48%; the corresponding survival rate was 41%. Over half the patients succumbed to distant metastases despite the majority of patients receiving chemotherapy. In this preliminary study, we have shown that heavy charged particle irradiation can be effectively used for control of bone sarcoma. A Phase II trial is warranted to determine optimal treatment for unresectable or gross residual disease.


Asunto(s)
Neoplasias Óseas/radioterapia , Sarcoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/mortalidad , Humanos , Traumatismos por Radiación , Sarcoma/tratamiento farmacológico , Sarcoma/mortalidad , Análisis de Supervivencia , Insuficiencia del Tratamiento
18.
Radiat Environ Biophys ; 31(3): 233-40, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1502331

RESUMEN

The feasibility of dynamic conformal heavy charged particle radiotherapy has been investigated at UCLBL, and shows high promise of: 1. an improved therapeutic ratio and 2. reduction in the number of treatment portals required for efficient treatment delivery. Assessment of dose to tumor and critical structures for several anatomical sites have been carried out using a normal tissue complication algorithm developed at LBL. For high-LET charged particle treatment delivery, dynamic conformal therapy using a raster scanned beam with variable modulation and multileaf collimator appears to be the optimal technique for treatment delivery.


Asunto(s)
Neoplasias/radioterapia , Aceleradores de Partículas , Transferencia de Energía , Humanos , Aceleradores de Partículas/instrumentación , Radioterapia/instrumentación , Radioterapia/métodos , Dosificación Radioterapéutica
19.
Int J Radiat Oncol Biol Phys ; 23(4): 881-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1618678

RESUMEN

Between June 1981 and May 1990, 11 patients with recurrent locally advanced nasopharyngeal carcinoma were treated with heavy charged particle radiation at Lawrence Berkeley Laboratory. All patients had previously undergone full course radiotherapy to a median dose of 70.2 Gy [range 61-81 Gy]. Median time to recurrence was 18.2 months. At the time of heavy charged particle radiotherapy treatment, all had evidence of invasion of the base of skull and 7 of 11 had cranial nerve deficits. None of the patients were candidates for brachytherapy because of tumor extent or poor geometry. The tumor histology was squamous cell carcinoma in 10 patients and lymphoepithelioma in one patient. Ten of the 11 patients had received chemotherapy prior to re-irradiation. The heavy charged particle tumor dose delivered ranged from 31.80 GyE to 62.30 GyE (average 50.25 GyE, median 50 GyE). Local control was achieved in 45%. Median survival was 42 months. Actuarial survival was 59% at 3 years and 31% at 5 years (Kaplan-Meier). There were no fatal complications. The results in treating locally advanced recurrent nasopharyngeal carcinoma with heavy charged particles appear superior to those reported by others using photon therapy.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Carcinoma de Células Escamosas/epidemiología , Helio , Iones , Neoplasias Nasofaríngeas/epidemiología , Neón , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos
20.
Int J Radiat Oncol Biol Phys ; 22(2): 295-303, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1740393

RESUMEN

Between 1976 and 1987, 52 patients with tumors adjacent to and/or involving the cervical, thoracic, or lumbar spinal cord were treated with charged particles at the University of California Lawrence Berkeley Laboratory. The histologies included chordoma and chondrosarcoma (24 pts), other bone and soft tissue sarcoma (14 pts), and metastatic or unusual histology tumors (14 pts). Radiation doses ranged from 29 to 80 Gray-equivalent (GyE), with a median dose of 70 GyE. Twenty-one patients received a portion of their treatment with photons. Median followup was 28 months. For 36 previously untreated patients, local control was achieved in 21/36 patients and the 3-year actuarial survival was 61%. Of 16 patients treated for recurrent disease, 7/16 were locally controlled and the 3-year actuarial survival was 51%. For patients treated for chordoma and chondrosarcoma, probability of local control was influenced by tumor volume (less than 100 cc or greater than 150 cc) and whether disease was recurrent or previously untreated. Complications occurred in 6/52 patients, including one spinal cord injury, one cauda equina and one brachial plexus injury, and three instances of skin or subcutaneous fibrosis. Charged particle radiotherapy can safely deliver high tumor doses to paraspinal tumors with good local control.


Asunto(s)
Condrosarcoma/radioterapia , Cordoma/radioterapia , Radioterapia de Alta Energía , Neoplasias de la Médula Espinal/radioterapia , Adolescente , Adulto , Anciano , Niño , Condrosarcoma/epidemiología , Condrosarcoma/mortalidad , Cordoma/epidemiología , Cordoma/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Neoplasias de la Médula Espinal/epidemiología , Neoplasias de la Médula Espinal/mortalidad , Tasa de Supervivencia , Estados Unidos/epidemiología
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