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2.
Clin Oncol (R Coll Radiol) ; 34(10): 683-689, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35688777

RESUMEN

AIMS: Patient-reported outcomes measures (PROMs) are an increasingly recognised end point of radiotherapy studies. We hypothesised that the baseline PROMs score is the strongest predictor for acute and late scores after treatment. We assessed the strength of association of baseline MD Anderson Symptom Inventory (MDASI) scores, alongside other known factors for patient- or clinician-reported toxicity, with acute (6-week) and late (12-month) scores in head and neck cancer (HNC) patients following (chemo)radiotherapy. MATERIALS AND METHODS: This was a retrospective analysis of longitudinal MDASI scores for 247 patients receiving (chemo)radiotherapy for HNC via multivariable linear regression. The factors investigated were: baseline symptom score, age, sex, concurrent chemotherapy, disease stage, radiotherapy fractionation, prior definitive surgery and performance status. Patients with a baseline score >4 in any item were defined as symptomatic in that category. RESULTS: Patients rated symptomatic for an MDASI item pre-treatment on average reported statistically (P < 0.0005) and clinically (>-1.5) significant reductions in scores 6 weeks and 12 months after (chemo)radiotherapy for all considered sub-items except taste, dryness of mouth and problems with teeth. Conversely patients asymptomatic at baseline reported a worsening of scores at both time points. Other investigated factors showed little association with changes in MDASI scores following treatment. CONCLUSIONS: Our data show that baseline MDASI scores are strongly associated with patient-reported toxicity 6 weeks and 12 months after (chemo)radiotherapy for HNC. Patients who are symptomatic at baseline can experience an early and durable benefit from treatment. This finding can inform discussions with patients before therapy and has implications for use of PROMs scores for the assessment of toxicity in randomised trials.


Asunto(s)
Neoplasias de Cabeza y Cuello , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos
4.
Anaesth Rep ; 9(1): 76-80, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33937778

RESUMEN

Cardioplegia is used to induce cardiac arrest in order to facilitate cardiac surgery in patients supported by cardiopulmonary bypass. It is administered directly into the coronary vessels after the heart has been isolated from the systemic circulation. We describe the case of a 9-year-old boy who mistakenly received 1 l of high strength St Thomas' Harefield cardioplegia solution delivered into the systemic circulation during cardiac surgery. Although the patient's heart did not stop, the subsequent physiological derangements were severe. The presenting features were refractory hypotension and dilutional anaemia along with severe hyperkalaemia, hypermagnesaemia and hyperchloraemic metabolic acidosis. Local anaesthetic systemic toxicity from the procaine contained within the cardioplegia solution was also a concern. Treatment required vasopressor administration and an extended period of cardiopulmonary bypass while serum electrolyte concentrations were corrected by haemodiafiltration. The systemic administration of cardioplegia solution is a rare but important iatrogenic clinical emergency that anaesthetists working in cardiac centres should be aware of. This case demonstrates that full recovery is possible.

5.
Nature ; 590(7847): 561-565, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33627814

RESUMEN

The fundamental building blocks of the proton-quarks and gluons-have been known for decades. However, we still have an incomplete theoretical and experimental understanding of how these particles and their dynamics give rise to the quantum bound state of the proton and its physical properties, such as its spin1. The two up quarks and the single down quark that comprise the proton in the simplest picture account only for a few per cent of the proton mass, the bulk of which is in the form of quark kinetic and potential energy and gluon energy from the strong force2. An essential feature of this force, as described by quantum chromodynamics, is its ability to create matter-antimatter quark pairs inside the proton that exist only for a very short time. Their fleeting existence makes the antimatter quarks within protons difficult to study, but their existence is discernible in reactions in which a matter-antimatter quark pair annihilates. In this picture of quark-antiquark creation by the strong force, the probability distributions as a function of momentum for the presence of up and down antimatter quarks should be nearly identical, given that their masses are very similar and small compared to the mass of the proton3. Here we provide evidence from muon pair production measurements that these distributions are considerably different, with more abundant down antimatter quarks than up antimatter quarks over a wide range of momenta. These results are expected to revive interest in several proposed mechanisms for the origin of this antimatter asymmetry in the proton that had been disfavoured by previous results4, and point to future measurements that can distinguish between these mechanisms.

9.
Br J Cancer ; 100(10): 1558-65, 2009 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-19384297

RESUMEN

The aims of this study were to assess changes in quality of life (QoL) scores in relation to radical radiotherapy for gynaecological cancer (before and after treatment up to 3 years), and to identify the effect that late treatment effects have on QoL. This was a prospective study involving 225 gynaecological cancer patients. A QoL instrument (European Organisation for the Research and Treatment of Cancer QLQ-C30) and late treatment effect questionnaire (Late Effects Normal Tissues - Subjective Objective Management Analysis) were completed before and after treatment (immediately after radiotherapy, 6 weeks, 12, 24 and 36 months after treatment). Most patients had acute physical symptoms and impaired functioning immediately after treatment. Levels of fatigue and diarrhoea only returned to those at pre-treatment assessment after 6 weeks. Patients with high treatment toxicity scores had lower global QoL scores. In conclusion, treatment with radiotherapy for gynaecological cancer has a negative effect on QoL, most apparent immediately after treatment. Certain late treatment effects have a negative effect on QoL for at least 2 years after radiotherapy. These treatment effects are centred on symptoms relating to the rectum and bowel, for example, diarrhoea, tenesmus and urgency. Future research will identify specific symptoms resulting from late treatment toxicity that have the greatest effect on QoL; therefore allowing effective management plans to be developed to reduce these symptoms and improve QoL in gynaecological cancer patients.


Asunto(s)
Neoplasias de los Genitales Femeninos/radioterapia , Calidad de Vida , Traumatismos por Radiación/fisiopatología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Terapia Combinada/efectos adversos , Femenino , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Neoplasias de los Genitales Femeninos/rehabilitación , Neoplasias de los Genitales Femeninos/cirugía , Humanos , Persona de Mediana Edad , Cooperación del Paciente , Traumatismos por Radiación/diagnóstico , Encuestas y Cuestionarios , Factores de Tiempo , Adulto Joven
10.
Heart ; 91(6): e48, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15894749

RESUMEN

Two infants underwent supra-annular placement of prosthetic mitral valves. The objective of this strategy was to insert a larger valve and delay replacement. This approach was initially successful but by two and three years later the patients developed impairment of cardiac function. The prosthesis decreased the volume and compliance of the left atrium causing high left atrial and pulmonary venous pressures. The "ventricularised" atrium below the prosthesis dilated. In neither case was it possible to delay second valve replacement.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Prótesis Valvulares Cardíacas/efectos adversos , Insuficiencia de la Válvula Mitral/cirugía , Femenino , Humanos , Lactante , Masculino , Falla de Prótesis , Reoperación
11.
Theor Appl Genet ; 111(2): 370-7, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15902396

RESUMEN

Resistance to grapevine powdery mildew is controlled by Run1, a single dominant gene present in the wild grapevine species, Muscadinia rotundifolia, but absent from the cultivated species, Vitis vinifera. Run1 has been introgressed into V. vinifera using a pseudo-backcross strategy, and genetic markers have previously been identified that are linked to the resistance locus. Here we describe the construction of comprehensive genetic and physical maps spanning the resistance locus that will enable future positional cloning of the resistance gene. Physical mapping was performed using a bacterial artificial chromosome (BAC) library constructed using genomic DNA extracted from a resistant V. vinifera individual carrying Run1 within an introgression. BAC contig assembly has enabled 20 new genetic markers to be identified that are closely linked to Run1, and the position of the resistance locus has been refined, locating the gene between the simple sequence repeat (SSR) marker, VMC4f3.1, and the BAC end sequence-derived marker, CB292.294. This region contains two multigene families of resistance gene analogues (RGA). A comparison of physical and genetic mapping data indicates that recombination is severely repressed in the vicinity of Run1, possibly due to divergent sequence contained within the introgressed fragment from M. rotundifolia that carries the Run1 gene.


Asunto(s)
Ascomicetos , Mapeo Cromosómico , Genes de Plantas/genética , Inmunidad Innata/genética , Enfermedades de las Plantas/microbiología , Vitaceae/genética , Cromosomas Artificiales Bacterianos , Repeticiones de Microsatélite/genética , Enfermedades de las Plantas/genética , Análisis de Secuencia de ADN
12.
Toxicol In Vitro ; 11(5): 633-6, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20654362

RESUMEN

Rhodamine B has been used as a histopathological stain for keratinization and cornification. Its ability as an in vitro indicator of the degree of epidermal keratinization was investigated in these preliminary studies. An immortalized human keratinocyte cell line, SVK-14, was evaluated as an alternative to primary human keratinocytes. The influence of extracellular calcium levels was evaluated alongside the effects of exposure to 1,25 (OH)(2) vitamin D(3) in serum-free and serum-containing media. Alamar blue (AB) conversion was used to measure changes in cellular reductive potential, and the amount of bound Rhodamine B relative to total protein per well was taken as an indicator of keratinization. Exposure to 1,25 (OH)(2) vitamin D(3) for 7 or 10 days did not increase Rhodamine B binding to confluent SVK-14 cultures, regardless of calcium concentration. Variation in Rhodamine B dye-binding to cells made it difficult to interpret the data. In addition, concern regarding the ability of SVK-14 cells to differentiate suggests that further studies need to be performed using normal human keratinocytes to validate this in vitro endpoint, with epidermal growth factor, insulin and hydrocortisone removed from the media to enhance epidermal differentiation.

13.
Toxicol In Vitro ; 11(5): 637-40, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20654363

RESUMEN

A reproducible, quantifiable assay has been developed for the measurement of esterase activity in human keratinocyte cultures, using the model substrate 4-methyl umbelliferyl heptanoate (MUH) which is hydrolysed to the fluorescent metabolite 4-methyl umbelliferone (MU). Activity was assessed in two human keratinocyte cell lines, NCTC 2544 and SVK-14, and in freshly isolated human breast keratinocytes from primary culture to passage 3. V(max) values for MUH hydrolysing activity in the two cell lines showed that the less differentiated cell line NCTC 2544 (V(max) = 23.00 +/- 2.84) expresses a much higher activity than SVK-14s (V(max) = 13.28 +/- 1.42) which are more differentiated and able to form a cornified envelope. Activity in the freshly isolated human breast keratinocytes decreased with time in culture in all three donors tested, which is also likely to relate to the extent of cell differentiation. In human skin, xenobiotic esters penetrating the stratum corneum may be exposed to changing levels of hydrolysing esterases as they are absorbed across the epidermal cell layers. The assay for MUH hydrolysis will be a useful tool for the study of esterase activity in populations of human keratinocytes in vitro.

14.
Environ Health Perspect ; 97: 201-8, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1396459

RESUMEN

Twenty-four Fischer 344 rats were exposed to enriched uranium dioxide (UO2) aerosols to give a mean initial lung burden of 291 +/- 89 (SD) micrograms. Groups of rats were killed at 1, 7, 180, 360, 540, and 720 days post-inhalation (PI). Their lungs were fixed and inflated. Sections cut from all five lung lobes were used to prepare CR-39 neutron-induced 235U fission fragment autoradiographs. A single traverse across a CR-39 autoradiograph of a tissue section, from the left lung of all the rats, was made using a motorized microscopic stage. The traverse was divided into 10 fields. The track counts per field were used to test for homogeneity of track distribution and to assess if there was any tendency for tracks to be related to the peripheral region of the lung. Full raster scans across the entire tissue image were made on left lung autoradiographs from two animals killed at each time point to assess the homogeneity of fission fragment track distribution throughout the entire section. There was no evidence of any temporal change in the proportion of tracks associated with the lung periphery. At all time points PI, the track distribution was significantly nonhomogeneous, suggesting a nonuniform pattern of tissue irradiation from the 234U alpha particles. At time points from 180 to 720 days PI, large clusters of macrophages were observed in some of the sections taken from all five lung lobes. The total number of macrophage clusters increased with time PI. These macrophage clusters produced many 235U fission fragment tracks within the CR-39 autoradiographs.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Pulmón/efectos de la radiación , Macrófagos Alveolares/patología , Compuestos de Uranio , Uranio/farmacocinética , Administración por Inhalación , Aerosoles , Animales , Autorradiografía , Relación Dosis-Respuesta en la Radiación , Pulmón/diagnóstico por imagen , Pulmón/metabolismo , Pulmón/patología , Masculino , Radiografía , Ratas , Ratas Endogámicas F344 , Distribución Tisular , Uranio/administración & dosificación
15.
Chem Biol Interact ; 26(3): 339-47, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-116777

RESUMEN

The principal products of the photooxidation of 7,12-dimethylbenz[a]-anthracene (DMBA) in aqueous solutions by photooxidation induced by laboratory lighting have been characterized by high performance liquid chromatograms (HPLC), ultraviolet and mass spectrograms and by comparisons with authentic samples. The products identified were the 7,12-epidioxy-7,12-dihydro-7-12-dimethyl-, 7,12-dione, 7-hydroxymethyl-12-methyl-, 12-hydroxymethyl-7-methyl-, 7-formyl-12-methyl-, 12-formyl-7-methyl-, and 12-hydroxy-12-methyl-7-one derivatives of benz[a]-anthracene. The HPLC profile of products is similar to that obtained from oxidation of DMBA by 'one-electron' reagents, singlet oxygen, or liver microsomal metabolism. The first points of attack are the 7- and 12- positions. The mechanism of photooxidation appears to be generation of singlet oxygen by photodynamic effect of DMBA. None of the products is photosensitizing, however.


Asunto(s)
9,10-Dimetil-1,2-benzantraceno , Benzo(a)Antracenos , Cromatografía Líquida de Alta Presión , Laboratorios , Espectrometría de Masas , Fotoquímica , Espectrofotometría Ultravioleta
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