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1.
J Small Anim Pract ; 60(8): 486-492, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31025384

RESUMEN

OBJECTIVES: To establish the utility of a novel in-house method of CSF analysis using sedimentation cytology direct from the spinal needle for the detection of laboratory-defined pleocytosis. MATERIALS AND METHODS: In dogs and cats undergoing routine CSF analysis for investigation of neurological signs, an additional preparation was made at the patient's side by inverting the spinal needle on a slide and sedimenting for at least 1 hour. Nucleated cellularity and differential counts were assessed and compared with "gold-standard" analysis. Variability of cell counts between observers and within slides using the new method was evaluated to optimise the procedure. RESULTS: Using a ×50 objective, at least 10 fields and an average of more than five cells per field were considered appropriate guidelines to achieve correct classification of samples (normal or pleocytosis). The new method had high sensitivity (89%) and specificity (100%) for the detection of laboratory-defined pleocytosis. Agreement on the type of pleocytosis was good. CLINICAL SIGNIFICANCE: Clinically useful information can be obtained from CSF samples in a patient-side setting without additional equipment. This technique may be of benefit if little fluid is available or if logistical constraints limit the availability of rapid specialist results.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Animales , Gatos , Recuento de Células/veterinaria , Citodiagnóstico/veterinaria , Perros , Sensibilidad y Especificidad
2.
Radiography (Lond) ; 23(4): e120-e121, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28965906

RESUMEN

INTRODUCTION: Breast cancer is increasingly a disease of the elderly, and combined with the NHS Breast Screening Extension means that more elderly patients are having mammography. Increasing age can make mammography more technically difficult. This is a technical note detailing the results of a local audit which may be of interest due to potential service implications. METHOD: A retrospective audit of the first year of screening extension of The Shropshire Breast Screening Programme. Aims to collect data on patient demographics and describe the technical adaptations developed in Shropshire. RESULTS: Breast screening extension has increased by 2.5 times the number of women aged 70-74 screened, and doubled the overall numbers of women over 70 screened. Significantly more older patients are being screened to present technical challenges to a screening programme. Data was obtained from a month of screening showed that 29% of patients over 70 needed extra time for positioning. Reasons included 22% difficulty in obtaining adequate positioning and 15% needed a relative to aid with consent. DISCUSSION: In the Shropshire screening programme different technical adaptations have been developed and are key to ensuring adequate images. These include double appointments, two radiographers, thorough assessment, steeper angles, seated examinations, from-below imaging and pre-planning for subsequent screen. CONCLUSION: Significantly more older women are having breast screening due to the increasing incidence of breast cancer and the Breast Screening Programme extension. Increasing age can significantly increase time taken for adequate imaging and present technical challenges. Development of technical adaptations to art of mammography is key to achieve adequate images.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Competencia Clínica , Mamografía/normas , Factores de Edad , Anciano , Inglaterra , Femenino , Humanos , Estudios Retrospectivos
3.
Oncogene ; 36(41): 5734-5744, 2017 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-28581517

RESUMEN

With very similar 3D structures, the widely expressed ß-arrestin isoforms 1 and 2 play at times identical, distinct or even opposing roles in regulating various aspects of G protein-coupled receptors (GPCR) expression and signalling. Recent evidence recognizes the ß-arrestin system as a key regulator of not only GPCRs, but also receptor tyrosine kinases, including the highly cancer relevant insulin-like growth factor type 1 receptor (IGF-1R). Binding of ß-arrestin1 to IGF-1R leads to ligand-dependent degradation of the receptor and generates additional MAPK/ERK signalling, protecting cancer cells against anti-IGF-1R therapy. Because the interplay between ß-arrestin isoforms governs the biological effects for most GPCRs, as yet unexplored for the IGF-1R, we sought to investigate specifically the regulatory roles of the ß-arrestin2 isoform on expression and function of the IGF-1R. Results from controlled expression of either ß-arrestin isoform demonstrate that ß-arrestin2 acts in an opposite manner to ß-arrestin1 by promoting degradation of an unstimulated IGF-1R, but protecting the receptor against agonist-induced degradation. Although both isoforms co-immunoprecipitate with IGF-1R, the ligand-occupied receptor has greater affinity for ß-arrestin1; this association lasts longer, sustains MAPK/ERK signalling and mitigates p53 activation. Conversely, ß-arrestin2 has greater affinity for the ligand-unoccupied receptor; this interaction is transient, triggers receptor ubiquitination and degradation without signalling activation, and leads to a lack of responsiveness to IGF-1, cell cycle arrest and decreased viability of cancer cells. This study reveals contrasting abilities of IGF-1R to interact with each ß-arrestin isoform, depending on the presence of the ligand and demonstrates the antagonism between the two ß-arrestin isoforms in controlling IGF-1R expression and function, which could be developed into a practical anti-IGF-1R strategy for cancer therapy.


Asunto(s)
Neoplasias/genética , Receptor IGF Tipo 1/genética , beta-Arrestinas/genética , Animales , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Ratones , Neoplasias/patología , Fosforilación , Unión Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteolisis , Receptor IGF Tipo 1/metabolismo , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genética , beta-Arrestinas/metabolismo
4.
Oncogene ; 36(23): 3274-3286, 2017 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-28092675

RESUMEN

Melanoma tumors usually retain wild-type p53; however, its tumor-suppressor activity is functionally disabled, most commonly through an inactivating interaction with mouse double-minute 2 homolog (Mdm2), indicating p53 release from this complex as a potential therapeutic approach. P53 and the tumor-promoter insulin-like growth factor type 1 receptor (IGF-1R) compete as substrates for the E3 ubiquitin ligase Mdm2, making their relative abundance intricately linked. Hence we investigated the effects of pharmacological Mdm2 release from the Mdm2/p53 complex on the expression and function of the IGF-1R. Nutlin-3 treatment increased IGF-1R/Mdm2 association with enhanced IGF-1R ubiquitination and a dual functional outcome: receptor downregulation and selective downstream signaling activation confined to the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway. This Nutlin-3 functional selectivity translated into IGF-1-mediated bioactivities with biphasic effects on the proliferative and metastatic phenotype: an early increase and late decrease in the number of proliferative and migratory cells, while the invasiveness was completely inhibited following Nutlin-3 treatment through an impaired IGF-1-mediated matrix metalloproteinases type 2 activation mechanism. Taken together, these experiments reveal the biased agonistic properties of Nutlin-3 for the mitogen-activated protein kinase pathway, mediated by Mdm2 through IGF-1R ubiquitination and provide fundamental insights into destabilizing p53/Mdm2/IGF-1R circuitry that could be developed for therapeutic gain.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Melanoma/patología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Receptor IGF Tipo 1/metabolismo , Neoplasias Cutáneas/patología , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis , Biomarcadores de Tumor/genética , Ciclo Celular , Proliferación Celular , Humanos , Melanoma/genética , Melanoma/metabolismo , Invasividad Neoplásica , Fenotipo , Proteínas Proto-Oncogénicas c-mdm2/genética , Receptor IGF Tipo 1/genética , Transducción de Señal , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/genética
5.
Prog Mol Biol Transl Sci ; 141: 277-311, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27378760

RESUMEN

Cell-surface receptors govern the critical information passage from outside to inside the cell and hence control important cellular decisions such as survival, growth, and differentiation. These receptors, structurally grouped into different families, utilize common intracellular signaling-proteins and pathways, yet promote divergent biological consequences. In rapid processing of extracellular signals to biological outcomes, posttranslational modifications offer a repertoire of protein processing options. Protein ubiquitination was originally identified as a signal for protein degradation through the proteasome system. It is now becoming increasingly recognized that both ubiquitin and ubiquitin-like proteins, all evolved from a common ubiquitin structural superfold, are used extensively by the cell and encompass signal tags for many different cellular fates. In this chapter we examine the current understanding of the ubiquitin regulation surrounding the insulin-like growth factor and insulin signaling systems, major members of the larger family of receptor tyrosine kinases (RTKs) and key regulators of fundamental physiological and pathological states.


Asunto(s)
Receptor IGF Tipo 1/metabolismo , Transducción de Señal , Ubiquitinación , Animales , Humanos , Modelos Biológicos , Fosforilación , Receptor de Insulina/metabolismo
6.
Vox Sang ; 108(3): 251-61, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25470076

RESUMEN

BACKGROUND AND OBJECTIVES: Febrile non-haemolytic transfusion reaction (FNHTR) is an acute transfusion complication resulting in fever, chills and/or rigours. Study's objective was to assess FNHTR occurrence and potential risk factors among inpatient U.S. elderly Medicare beneficiaries, ages 65 and older, during 2011-2012. MATERIALS AND METHODS: Our retrospective claims-based study utilized large Medicare administrative databases. FNHTR was ascertained via ICD-9-CM diagnosis code, and transfusions were identified by recorded procedure and revenue centre codes. The study ascertained FNHTR rates among the inpatient elderly overall and by age, gender, race, blood components and units transfused. Multivariate logistic regression analyses were used to assess potential risk factors. RESULTS: Among 4 336 338 inpatient transfusion stays for elderly during 2011-2012, 2517 had FNHTR diagnosis recorded, an overall rate of 58.0 per 100,000 stays. FNHTR rates (per 100,000 stays) varied by age, gender, number of units and blood components transfused. FNHTR rates were substantially higher for RBCs- and platelets-containing transfusions as compared to plasma only. Significantly higher odds of FNHTR were identified with greater number of units transfused (P < 0.01), for females vs. males (OR = 1.15, 95% CI 1.04-1.27), and with 1-year histories of transfusion (OR = 1.25, 95% CI 1.10-1.42), lymphoma (OR = 1.22, 95% CI 1.02-1.46), leukaemia (OR = 1.90, 95% CI 1.56-2.31) and other diseases. CONCLUSIONS: Our study shows increased FNHTR occurrence among elderly with greater number of units and with RBCs- and platelets-containing transfusions, suggesting need to evaluate effectiveness of prestorage leucoreduction in elderly. The study also suggests importance of prior recipient alloimmunization and underlying health conditions in the development of FNHTR.


Asunto(s)
Medicare/estadística & datos numéricos , Reacción a la Transfusión , Reacción a la Transfusión/epidemiología , Anciano , Anciano de 80 o más Años , Transfusión Sanguínea/métodos , Transfusión Sanguínea/estadística & datos numéricos , Femenino , Humanos , Pacientes Internos/estadística & datos numéricos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Reacción a la Transfusión/prevención & control , Estados Unidos
7.
Vox Sang ; 106(2): 144-52, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23848234

RESUMEN

BACKGROUND AND OBJECTIVES: Transfusion-associated circulatory overload (TACO) is a serious transfusion complication resulting in respiratory distress. The study's objective was to assess TACO occurrence and potential risk factors among elderly Medicare beneficiaries (ages 65 and older) in the inpatient setting during 2011. MATERIALS AND METHODS: This retrospective claims-based study utilized Medicare administrative databases in coordination with Centers for Medicare & Medicaid Services. Transfusions were identified by recorded procedure and revenue centre codes, while TACO was ascertained via ICD-9-CM diagnosis code. We evaluated TACO diagnosis code rates overall and by age, gender, race, number of units and blood components transfused. Multivariate logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 2,147,038 inpatient transfusion stays for elderly in 2011, 1340 had TACO diagnosis code, overall rate of 62·4 per 100,000 stays. TACO rates increased significantly with age and units transfused (P < 0·0001). After adjustment for confounding, significantly higher odds of TACO were found for women vs. men (OR = 1·40, 95% CI 1·26-1·60), White people vs. non-White people (OR = 1·38, 95% CI 1·20-1·62) and persons with congestive heart failure (OR = 1·61, 95% CI 1·44-1·88), chronic pulmonary disease (OR = 1·19, 95% CI 1·08-1·32) and different anaemias. CONCLUSION: Our study identified largest number of potential TACO cases to date and showed a substantial increase in TACO occurrence with age and number of units transfused. The study suggested increased TACO risk in elderly with congestive heart failure, chronic pulmonary disease and anaemias. Overall, study shows importance of large administrative databases as an additional epidemiological tool.


Asunto(s)
Trastornos Respiratorios/etiología , Reacción a la Transfusión , Anciano , Anciano de 80 o más Años , Transfusión de Componentes Sanguíneos/efectos adversos , Bases de Datos Factuales , Femenino , Hospitalización , Humanos , Masculino , Medicare , Trastornos Respiratorios/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos
8.
Opt Lett ; 32(9): 1141-3, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17410262

RESUMEN

Terahertz diffractive optic elements have been fabricated in polypropylene by imprinting with a silicon master. A silicon master is created with eight phase levels for high diffraction efficiency and etched using inductively coupled plasma reactive ion etching. This technique enables the rapid replication of complex optical structures in a high transmission material. Excellent replication of multilevel high efficiency Fresnel lenses is shown. The resulting lenses were tested with a 2 THz quantum cascade laser. The signal strength at the focus was 70 times the base signal strength.

10.
Hum Genet ; 76(2): 186-90, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3475247

RESUMEN

Friedreich ataxia, a progressive neurodegenerative disorder, is an autosomal recessive disease with a carrier frequency of 1/110 in the United Kingdom. The pathophysiological basis for the disease is not known and the chromosomal location of the mutation remains unidentified. As part of an attempt to map the mutation using linked DNA markers, we demonstrate that the Friedreich ataxia gene is excluded from human chromosome 19. This study also demonstrates that the insulin receptor, which maps to chromosome 19 and may be associated with abnormal biochemical features in some patients, is not the basic defect.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 19 , Ataxia de Friedreich/genética , Ligamiento Genético , Alelos , ADN/genética , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Humanos , Masculino , Mutación , Hibridación de Ácido Nucleico , Linaje , Receptor de Insulina/genética
11.
J Med Genet ; 23(4): 295-9, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3018247

RESUMEN

Cloned DNA markers which are closely linked to the gene defect causing cystic fibrosis have recently been described. These markers are sufficiently informative for carrier detection in 80% of families where there is a living cystic fibrosis child and unaffected sibs. The tightly linked DNA marker pJ3.11 was used in this study to identify carriers in six families and exclude carrier status in two subjects. Risk calculations for recessive diseases using linked DNA probes may be complex, but useful information for counselling can be obtained in this way.


Asunto(s)
Fibrosis Quística/diagnóstico , Tamización de Portadores Genéticos/métodos , Clonación Molecular , Fibrosis Quística/genética , Enzimas de Restricción del ADN , Ligamiento Genético , Humanos , Linaje , Polimorfismo Genético
13.
Oecologia ; 59(1): 18-26, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25024142

RESUMEN

Fecundity, reproductive effort (estimated both from production measurements and from physiological data), the energetic costs of reproduction and the reproductive value of different size classes were measured for mussels at different sites and related to age and to tissue weight. Variability between sites was considerable and differences as great as 10 x were recorded between minimum and maximum values for egg production, reproductive effort and reproductive value. However, similarities between mussels from different sites were also apparent, as regards egg size, the estimated metabolic costs of egg production (based on measurements of oxygen consumption), the relationship (isometric) between egg production and body size, the fact of an increase in reproductive effort with increase in size, and the age at which maximum residual reproductive values was expressed. These relationships are discussed in terms of the fundamental reproductive strategy of the species and the degree of environmental stress imposed on the mussels at the different sites.

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