RESUMEN
It is evident that there is a nuclear skills shortage within the UK, and logically it can be assumed that the shortfall extends to the radiation protection arena. Plans for nuclear new-build and the decommissioning of existing nuclear sites will require many more people with radiological knowledge and practical competencies. This converts to a nuclear industry requirement in the order of 1000 new recruits per year over at least the next ten years, mainly as new apprentices and graduates. At the same time, the strong demand for persons with radiation protection know-how in the non-nuclear and health care sectors is unlikely to diminish. The task of filling this skills gap is a significant one and it will require a determined effort from many UK stakeholders. The Society for Radiological Protection (SRP) has adopted a strategy in recent years to help address this skills gap. The aim is to engage the interest of secondary school students in the science of radiation and inspire them to follow a career in radiation protection. This paper presents the reasoning behind this strategy and, in an 'outreach case study', describes the establishment of the annual SRP Schools Event. This event is becoming an important addition to the national efforts aimed at increasing the numbers of skilled UK radiation protection professionals over the forthcoming decades.
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Protección Radiológica , Radiología , Selección de Profesión , Predicción , Humanos , Instituciones Académicas , Reino Unido , Recursos HumanosRESUMEN
OBJECTIVE: Bisphosphonates are considered potential disease modifying osteoarthritis (OA) agents. The present study investigated the efficacy of pre-emptive, early, and delayed alendronate (ALN) treatment initiation on subchondral trabecular bone and cartilage in low-dose monosodium iodoacetate (MIA)-induced knee OA in rats. METHODS: Male rats received pre-emptive (n = 12, day 0-end of week 2), early (n = 12, end of week 2-end of week 6), or delayed (n = 12, end of week 6-end of week 10) ALN treatment (30 µg/kg/week). Pre-emptive ALN-treated rats were scanned using in vivo micro-computed tomography (micro-CT) after 2 weeks and then sacrificed, early ALN-treated rats were scanned after 2 and 6 weeks and sacrificed, and the delayed ALN-treated rats were scanned after 2, 6, and 10 weeks of OA induction and sacrificed. After sacrifice, bone histomorphometry and histology of the tibia and biomarker analyses were undertaken. Changes in hind limb weight-bearing were assessed from day -1 until day 14. RESULTS: MIA-induced pathological features similar to progressive human OA in the cartilage and subchondral bone. Pre-emptive ALN treatment preserved subchondral trabecular bone microarchitecture, prevented bone loss, decreased bone turnover and joint discomfort. Pre-emptive ALN treatment had moderate effects on cartilage degradation. Early and delayed ALN treatments prevented loss of trabeculae and decreased bone turnover, but had no significant effect on cartilage degradation. CONCLUSION: ALN prevented increased bone turnover and preserved the structural integrity of subchondral bone in experimental OA. The time point of treatment initiation is crucial for treating OA. Treating both the subchondral bone and cartilage in OA would be clinically more beneficial.
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Alendronato/uso terapéutico , Artritis Experimental/tratamiento farmacológico , Conservadores de la Densidad Ósea/uso terapéutico , Cartílago Articular/efectos de los fármacos , Osteoartritis de la Rodilla/tratamiento farmacológico , Alendronato/administración & dosificación , Alendronato/farmacología , Animales , Artritis Experimental/diagnóstico por imagen , Artritis Experimental/metabolismo , Artritis Experimental/patología , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/farmacología , Proteína de la Matriz Oligomérica del Cartílago/sangre , Cartílago Articular/patología , Colágeno Tipo I/sangre , Colágeno Tipo II/orina , Esquema de Medicación , Evaluación Preclínica de Medicamentos/métodos , Masculino , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , Fragmentos de Péptidos/orina , Péptidos/sangre , Ratas , Ratas Wistar , Tibia/diagnóstico por imagen , Tibia/efectos de los fármacos , Tibia/patología , Microtomografía por Rayos XRESUMEN
Pre-targeting of bispecific antibodies is probed to enhance tumour retention while limiting clearance of administered multifunctional branched PEGylated nanomedicines. The temporal influence of pre-targeting on polymer interaction with tumour cells and tissue is explored using in vitro assays through to preclinical validation.
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Anticuerpos Biespecíficos , Nanoestructuras , Neoplasias , Humanos , Nanomedicina , Neoplasias/tratamiento farmacológico , PolímerosRESUMEN
Tissues require an adequate supply of oxygen in order to maintain normal cell function. Low oxygen tension (hypoxia) is characteristic of a number of conditions, including cancer, atherosclerosis, rheumatoid arthritis, critical limb ischaemia, peripheral vascular disease, and ischaemic heart disease. Tissue hypoxia is found in tumours, atherosclerotic plaque, and ischaemic myocardium. There is a growing interest in methods to detect and assess hypoxia, given that hypoxia is important in the progression of these diseases. Hypoxia can be assessed at the level of the whole organ, tissue, or cell, using both invasive and non-invasive methods, and by a range of immunohistochemical, biochemical, or imaging techniques. This review describes and critiques current methods of assessing hypoxia that are used at the bench and in clinical practice.
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Tecnología Biomédica/métodos , Hipoxia/diagnóstico , Animales , Hipoxia de la Célula , HumanosRESUMEN
Better convenience and tolerability and sustained therapeutic concentrations might improve interferon (IFN) treatment for chronic hepatitis C virus (HCV) infection. In an open-label, randomized study, controlled release free (chemically unmodified) recombinant human IFN-α(2b) in poly(ether-ester) microspheres (CR-rhIFN-α(2b)), was injected at doses of 160, 320, 480 or 640 µg every 2 weeks for 12 weeks with concomitant weight-based oral ribavirin in 32 treatment-naïve patients with chronic HCV genotype 1. Treatment was well tolerated, with 31 patients (97%) successfully completing the study. Full doses of CR-rhIFN-α(2b) were administered on 96% of scheduled occasions. Flu-like symptoms were generally mild and brief. Injection site reactions developed in 13 patients (41%), and neutropenia occurred in six of eight patients receiving 640 µg. In the 320, 480 and 640 µg groups, 62-75% of patients achieved a ≥2 log(10) HCV RNA reduction by 4 weeks and 88-100% by 12 weeks. For those groups, the pooled median time to ≥2 log(10) reduction was 11 days (95% confidence interval, 7-35 days). In those groups, viral reduction below the limit of detection was accomplished in 25% of patients by 4 weeks and in 62% by 12 weeks. The 160-µg dose was less potent. After CR-rhIFN-α(2b) injection, stable plateau levels of serum IFN-α(2b) were generally reached within 72 h. Treatment-emergent neutralizing antibodies to IFN-α(2b) were observed in one patient. No antibodies to host plant proteins were detected. CR-rhIFN-α(2b) with ribavirin cotherapy was well tolerated and displayed potent early antiviral activity in patients with chronic HCV genotype 1.
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Antivirales/administración & dosificación , Preparaciones de Acción Retardada , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/efectos adversos , Quimioterapia Combinada/métodos , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Humanos , Interferón alfa-2 , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Ribavirina/administración & dosificación , Ribavirina/efectos adversos , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: Rapid thrombus recanalization reduces the incidence of post-thrombotic complications. This study aimed to discover whether adenovirus-mediated transfection of the vascular endothelial growth factor gene (ad.VEGF) enhanced thrombus recanalization and resolution. METHODS AND RESULTS: In rats, thrombi were directly injected with either ad.VEGF (n=40) or ad.GFP (n=37). Thrombi in SCID mice (n=12) were injected with human macrophages transfected with ad.VEGF or ad.GFP. Thrombi were analyzed at 1 to 14 days. GFP was found mainly in the vein wall and adventitia by 3 days, but was predominantly found in cells within the body of thrombus by day 7. VEGF levels peaked at 4 days (376+/-299 pg/mg protein). Ad.VEGF treatment reduced thrombus size by >50% (47.7+/-5.1 mm(2) to 22.0+/-4.0 mm(2), P=0.0003) and increased recanalization by >3-fold (3.9+/-0.69% to 13.6+/-4.1%, P=0.024) compared with controls. Ad.VEGF treatment increased macrophage recruitment into the thrombus by more than 50% (P=0.002). Ad.VEGF-transfected macrophages reduced thrombus size by 30% compared with controls (12.3+/-0.89 mm(2) to 8.7+/-1.4 mm(2), P=0.04) and enhanced vein lumen recanalization (3.39+/-0.34% to 5.07+/-0.57%, P=0.02). CONCLUSIONS: Treatment with ad.VEGF enhanced thrombus recanalization and resolution, probably as a consequence of an increase in macrophage recruitment.
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Adenoviridae/genética , Técnicas de Transferencia de Gen , Terapia Genética/métodos , Vectores Genéticos , Macrófagos/trasplante , Factor A de Crecimiento Endotelial Vascular/metabolismo , Trombosis de la Vena/terapia , Animales , Línea Celular , Modelos Animales de Enfermedad , Genes Reporteros , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , Ratones , Ratones SCID , Ratas , Ratas Wistar , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Trombosis de la Vena/genética , Trombosis de la Vena/metabolismo , Trombosis de la Vena/patologíaRESUMEN
The neonatal crystallizable fragment receptor (FcRn) functions as an intracellular protection receptor for immunoglobulin G (IgG). Recently, several clinical studies have reported the lowering of circulating monomeric IgG levels through FcRn blockade for the potential treatment of autoimmune diseases. Many autoimmune diseases, however, are derived from the effects of IgG immune complexes (ICs). We generated, characterized, and assessed the effects of SYNT001, a FcRn-blocking monoclonal antibody, in mice, nonhuman primates (NHPs), and humans. SYNT001 decreased all IgG subtypes and IgG ICs in the circulation of humans, as we show in a first-in-human phase 1, single ascending dose study. In addition, IgG IC induction of inflammatory pathways was dependent on FcRn and inhibited by SYNT001. These studies expand the role of FcRn in humans by showing that it controls not only IgG protection from catabolism but also inflammatory pathways associated with IgG ICs involved in a variety of autoimmune diseases.
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Anticuerpos Monoclonales Humanizados/farmacocinética , Anticuerpos Monoclonales/farmacocinética , Complejo Antígeno-Anticuerpo/inmunología , Inmunidad Humoral/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Receptores Fc/antagonistas & inhibidores , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Autoanticuerpos/efectos de los fármacos , Enfermedades Autoinmunes/tratamiento farmacológico , Estudios de Cohortes , Método Doble Ciego , Femenino , Voluntarios Sanos , Antígenos de Histocompatibilidad Clase I , Humanos , Macaca fascicularis , Masculino , Ratones , Unión ProteicaRESUMEN
BACKGROUND: The aim of this study was to examine the effect of statin treatment on the activity of proteases in the wall of abdominal aortic aneurysms (AAAs). METHODS: The activities of matrix metalloproteinases (MMPs) 9 and 3, cathepsins B, H, K, L and S, and the cystatin C level were measured in extracts of AAA wall taken from 82 patients undergoing AAA repair; 21 patients were receiving statin treatment before surgery. All values were standardized against soluble protein (SP) concentration in the extract, and reported as median (interquartile range) or mean(s.e.m.). RESULTS: The two groups had similar demographics. Reduced activity of MMP-9 (43 (34-56) versus 80 (62-110) pg per mg SP; P < 0.001), cathepsin H (183 (117-366) versus 321 (172-644) nmol 4-methylcoumarin-7-amide released per mg SP; P = 0.016) and cathepsin L (102 (51-372) versus 287 (112-816) micromol 7-amino-4-trifluoromethylcoumarin released per mg SP; P = 0.020) was found in the statin-treated aortas compared with AAAs from patients not taking a statin. The statin-treated group had lower MMP-3 activity, but this did not reach statistical significance (P = 0.053). Cystatin C levels were higher in statin-treated aortas than in controls (41.3(3.1) versus 28.9(2.1) ng per mg SP; P = 0.003). CONCLUSION: Statins decreased the activity of proteases that have been implicated in aneurysm disease.
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Aorta Abdominal/enzimología , Aneurisma de la Aorta Abdominal/enzimología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Metaloproteinasa 3 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Anciano , Catepsinas/metabolismo , Cistatina C , Cistatinas/metabolismo , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , MasculinoRESUMEN
BACKGROUND: Hypoxia within acute venous thrombi is thought to drive resolution through stabilisation of hypoxia inducible factor 1 alpha (HIF1α). Prolyl hydroxylase domain (PHD) isoforms are critical regulators of HIF1α stability. Non-selective inhibition of PHD isoforms with l-mimosine has been shown to increase HIF1α stabilisation and promote thrombus resolution. OBJECTIVE: The aim of this study was to investigate the therapeutic potential of PHD inhibition in venous thrombus resolution. METHODS: Thrombosis was induced in the inferior vena cava of mice using a combination of flow restriction and endothelial activation. Gene and protein expression of PHD isoforms in the resolving thrombus was measured by RT-PCR and immunohistochemistry. Thrombus resolution was quantified in mice treated with pan PHD inhibitors AKB-4924 and JNJ-42041935 or inducible all-cell Phd2 knockouts by micro-computed tomography, 3D high frequency ultrasound or endpoint histology. RESULTS: Resolving venous thrombi demonstrated significant temporal gene expression profiles for PHD2 and PHD3 (Pâ¯<â¯0.05), but not for PHD1. PHD isoform protein expression was localised to early and late inflammatory cell infiltrates. Treatment with selective pan PHD inhibitors, AKB-4924 and JNJ-42041935, enhanced thrombus neovascularisation (Pâ¯<â¯0.05), but had no significant effect on overall thrombus resolution. Thrombus resolution or its markers, macrophage accumulation and neovascularisation, did not differ significantly in inducible all-cell homozygous Phd2 knockouts compared with littermate controls (Pâ¯>â¯0.05). CONCLUSIONS: This data suggests that PHD-mediated thrombus neovascularisation has a limited role in the resolution of venous thrombi. Directly targeting angiogenesis alone may not be a viable therapeutic strategy to enhance venous thrombus resolution.
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Bencimidazoles/uso terapéutico , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Neovascularización Fisiológica/efectos de los fármacos , Piperazinas/uso terapéutico , Procolágeno-Prolina Dioxigenasa/antagonistas & inhibidores , Pirazoles/uso terapéutico , Piridonas/uso terapéutico , Trombosis/tratamiento farmacológico , Animales , Femenino , Humanos , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Procolágeno-Prolina Dioxigenasa/genética , Trombosis/genética , Trombosis/patología , TranscriptomaRESUMEN
OBJECTIVES: This fourteen-centre project used professional rating scales and parent questionnaires to assess longitudinal outcomes in a large non-selected population of children receiving simultaneous and sequential bilateral cochlear implants. METHODS: This was an observational non-randomized service evaluation. Data were collected at four time points: before bilateral cochlear implants or before the sequential implant, one year, two years, and three years after. The measures reported are Categories of Auditory Performance II (CAPII), Speech Intelligibility Rating (SIR), Bilateral Listening Skills Profile (BLSP) and Parent Outcome Profile (POP). RESULTS: Thousand and one children aged from 8 months to almost 18 years were involved, although there were many missing data. In children receiving simultaneous implants after one, two, and three years respectively, median CAP scores were 4, 5, and 6; median SIR were 1, 2, and 3. Three years after receiving simultaneous bilateral cochlear implants, 61% of children were reported to understand conversation without lip-reading and 66% had intelligible speech if the listener concentrated hard. Auditory performance and speech intelligibility were significantly better in female children than males. Parents of children using sequential implants were generally positive about their child's well-being and behaviour since receiving the second device; those who were less positive about well-being changes also generally reported their children less willing to wear the second device. CONCLUSION: Data from 78% of paediatric cochlear implant centres in the United Kingdom provide a real-world picture of outcomes of children with bilateral implants in the UK. This large reference data set can be used to identify children in the lower quartile for targeted intervention.
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Implantación Coclear/psicología , Implantes Cocleares/psicología , Pérdida Auditiva Bilateral/cirugía , Padres/psicología , Satisfacción del Paciente/estadística & datos numéricos , Adolescente , Niño , Preescolar , Implantación Coclear/métodos , Femenino , Pérdida Auditiva Bilateral/psicología , Humanos , Lactante , Masculino , Periodo Posoperatorio , Inteligibilidad del Habla , Percepción del Habla , Encuestas y Cuestionarios , Resultado del Tratamiento , Reino UnidoRESUMEN
OBJECTIVES: To assess longitudinal outcomes in a large and varied population of children receiving bilateral cochlear implants both simultaneously and sequentially. METHODS: This observational non-randomized service evaluation collected localization and speech recognition in noise data from simultaneously and sequentially implanted children at four time points: before bilateral cochlear implants or before the sequential implant, 1 year, 2 years, and 3 years after bilateral implants. No inclusion criteria were applied, so children with additional difficulties, cochleovestibular anomalies, varying educational placements, 23 different home languages, a full range of outcomes and varying device use were included. RESULTS: 1001 children were included: 465 implanted simultaneously and 536 sequentially, representing just over 50% of children receiving bilateral implants in the UK in this period. In simultaneously implanted children the median age at implant was 2.1 years; 7% were implanted at less than 1 year of age. In sequentially implanted children the interval between implants ranged from 0.1 to 14.5 years. Children with simultaneous bilateral implants localized better than those with one implant. On average children receiving a second (sequential) cochlear implant showed improvement in localization and listening in background noise after 1 year of bilateral listening. The interval between sequential implants had no effect on localization improvement although a smaller interval gave more improvement in speech recognition in noise. Children with sequential implants on average were able to use their second device to obtain spatial release from masking after 2 years of bilateral listening. Although ranges were large, bilateral cochlear implants on average offered an improvement in localization and speech perception in noise over unilateral implants. CONCLUSION: These data represent the diverse population of children with bilateral cochlear implants in the UK from 2010 to 2012. Predictions of outcomes for individual patients are not possible from these data. However, there are no indications to preclude children with long inter-implant interval having the chance of a second cochlear implant.
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Implantación Coclear/métodos , Implantes Cocleares , Pérdida Auditiva Bilateral/cirugía , Localización de Sonidos , Percepción del Habla , Adolescente , Niño , Preescolar , Demografía , Femenino , Humanos , Estudios Longitudinales , Masculino , Ruido , Ensayos Clínicos Controlados no Aleatorios como Asunto , Periodo Posoperatorio , Resultado del Tratamiento , Reino UnidoRESUMEN
Shessel et al. (Invest. Urol., 17: 529-533, 1980) have reported previously that the serially transplantable Dunning R-3327-G rat prostatic, adenocarcinoma grows faster in intact versus castrated male rats. The present study has demonstrated that this is because the G tumor is composed of androgen-independent but -sensitive prostatic cancer cells. The inclusion that G tumor cells are androgen independent is based upon the observations that these cells are capable of growing following inoculation into castrated male rats and that castration of intact male rats bearing established G tumors induces neither regression of tumor volume nor cessation of the continuous growth of the tumor. The G tumor cells, while being androgen independent, are, however, highly sensitive to androgen for their maximal rate of tumor growth. This androgen sensitivity is demonstrated by the fact that the G tumor cells can be reversibly shifted to a faster or slower growth rate simply by manipulation of the host androgen status. The androgen sensitivity of G tumor growth rate is unusual in that it is not due to androgenic stimulation of cell division but to androgen-induced inhibition of G tumor cell loss (i.e., the rate of G tumor cell loss is reduced by over 50% when androgen is present). The androgen sensitivity of G tumor cell loss is also unusual in that, due to the low level of 5 alpha-reductase activity of the G tumor, the predominant intracellular androgen responsible for this inhibition in untreated intact hosts appears to be testosterone and not dihydrotestosterone (DHT). In castrated rats, however, exogenous treatment with DHT is equally as effective as exogenous testosterone in inhibiting G tumor cell loss. These results suggest that G tumor cells are sensitive to either testosterone or DHT but that in untreated intact hosts little DHT is formed by the tumor cells.
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Adenocarcinoma/fisiopatología , Andrógenos/fisiología , Neoplasias de la Próstata/fisiopatología , Testosterona/farmacología , Adenocarcinoma/metabolismo , Andrógenos/metabolismo , Animales , Castración , División Celular/efectos de los fármacos , Cinética , Masculino , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/fisiopatología , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Ratas , Testosterona/metabolismoRESUMEN
Cellular adhesion and spreading are critical components involved in the processes of cell and tissue development, and immune responses in molluscs, but at present, little is known regarding the signaling pathways involved in these basic cellular functions. In the present study, the molluscan Biomphalaria glabrata embryonic (Bge) cell line was used as an in vitro model to study the signal transduction pathways regulating molluscan cell adhesion and spreading behavior. Western blot analysis using antibodies specific to mitogen-activated protein kinase (MAPK) revealed the presence of an MAPK-like immunoreactive protein in Bge cells, that was phosphorylated upon exposure to phorbol myristate acetate (PMA). Moreover, Bge cell treatment with inhibitors of protein kinase C (PKC), Ras and MAPK kinase (Mek) suppressed PMA-induced expression of activated MAPK, suggesting that PKC-, Ras- and Mek-like molecules may be acting upstream of MAPK. Similarly, in vitro Bge cell-spreading assays were performed in conjunction with the same panel of inhibitors to determine the potential involvement of PKC, Ras and Mek in cellular adhesion/spreading. Results revealed a similar pattern of inhibition of cell-spreading behavior strongly implying that the Bge cell spreading also may be regulated through a MAPK-associated signal transduction pathway(s) involving proteins similar to PKC, Ras and Mek.
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Biomphalaria/embriología , Proteína Quinasa C/fisiología , Alcaloides , Animales , Benzofenantridinas , Línea Celular , Activación Enzimática , Proteínas Quinasas Activadas por Mitógenos/análisis , Proteínas Quinasas Activadas por Mitógenos/fisiología , Naftalenos/farmacología , Fenantridinas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Transducción de SeñalRESUMEN
The prognostic variables from predischarge coronary angiography and left ventriculography in survivors of acute myocardial infarction during the years 1974 to 1978 were evaluated in 143 patients (less than or equal to 66 years of age) with documented myocardial infarction who were then followed up prospectively for 5 years. One half of the study population had triple vessel coronary disease (greater than or equal to 50% stenosis). However, only 7% of patients had severely depressed left ventricular function with an ejection fraction less than or equal to 29%. Evaluation of the contribution of many clinical and angiographic variables to a first cardiac event (death, nonfatal reinfarction or coronary artery bypass surgery) was considered with Kaplan-Meier actuarial curves and multivariate Cox's hazard function analysis. A risk segment was defined as an area of contracting myocardium supplied by a coronary artery with a greater than 50% stenosis. Multivariate analysis demonstrated that right plus left anterior descending coronary artery stenoses (p less than 0.01), ejection fraction (p less than 0.01) and the presence of risk segments (p less than 0.05) were significant predictors of outcome. Furthermore, on separate multivariate analyses, the angiographic variables added significantly to the clinical variables to predict cardiac events over 5 years of follow-up. Therefore, in survivors of acute myocardial infarction who undergo cardiac catheterization, additive prognostic information is obtained that can be used to stratify risk over 5 years.
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Cateterismo Cardíaco , Infarto del Miocardio/mortalidad , Volumen Sistólico , Angiografía Coronaria , Muerte Súbita/etiología , Electrocardiografía , Estudios de Seguimiento , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/cirugía , Alta del Paciente , Probabilidad , Pronóstico , Estudios ProspectivosRESUMEN
Chemical and recombinant methods have continued to complement one another in the synthesis of protein analogues. Chemical methods remain particularly valuable when non-coded modifications are to be introduced, although it has been accepted since the commercialization of semisynthetic human insulin that they can also be used effectively for coded changes, in certain cases. The main objective of all such operations is not methodological, but is the production of molecules for practical use and further study. This goal has been reached frequently by chemical means during the past year.
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Proteínas/síntesis química , Secuencia de Bases , ADN , Humanos , Datos de Secuencia Molecular , Proteínas/metabolismoRESUMEN
BACKGROUND: Portable instruments that measure the prothrombin time and automatically calculate the international normalized ratio (INR) with the use of a drop of whole blood have simplified the treatment of patients who are receiving warfarin therapy. The accuracy of these portable monitors has never been determined by comparing INR results with a criterion (gold) standard INR determination. METHODS: Duplicate whole-blood INR determinations were made with two commercially available portable INR monitors. Duplicate frozen-plasma samples were measured with four different thromboplastin reagents, each with a different international sensitivity index. The criterion standard INR was determined by using an international reference thromboplastin and the manual tilt-tube technique. Agreement was evaluated by determining how accurately laboratory and monitor INR determinations matched criterion standard values in designating a sample to be within or outside of currently recommended INR target ranges. RESULTS: Two of the laboratory methods, which used relatively sensitive thromboplastins, showed close agreement with the criterion standard, whereas two laboratory methods that used less sensitive thromboplastin reagents showed poor agreement. Both of the portable monitors fell between these extremes. The two best laboratory methods ere significantly better (P < .003) than both monitors, which in turn were better (P < .003) than the remaining two laboratories. CONCLUSIONS: There is large interlaboratory variation in the accuracy of INR determinations. Laboratory methods that used insensitive (high international sensitivity index) thromboplastins performed poorly. Accuracy of monitor measurements appears satisfactory.
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Monitoreo de Drogas/normas , Tiempo de Protrombina , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/farmacología , Monitoreo de Drogas/métodos , Femenino , Humanos , Laboratorios/normas , Masculino , Persona de Mediana Edad , Warfarina/farmacologíaRESUMEN
D-dimer fragments can be measured easily in plasma and whole blood, and the presence or absence of D-dimer could be useful in the diagnostic evaluation of venous thromboembolism. We systematically reviewed the English literature for articles that compared D-dimer results with those of other tests for deep venous thrombosis or pulmonary embolism. Twenty-nine studies were selected for detailed review, and we noted wide variability in assay performance, heterogeneity among subjects, and failure to define absence or presence of venous thromboembolism by a comprehensive criterion standard for diagnosis. These methodologic problems limit the generalizability of the published estimates of D-dimer accuracy for deep venous thrombosis or pulmonary embolism, and the clinical utility of this potentially important test remains unproved.
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Productos de Degradación de Fibrina-Fibrinógeno/análisis , Embolia Pulmonar/diagnóstico , Tromboflebitis/diagnóstico , Enfermedad Aguda , Ensayo de Inmunoadsorción Enzimática , Humanos , Técnicas de Inmunoadsorción , Pruebas de Fijación de LátexRESUMEN
A detailed study of the activity of LHRH analog antagonists has been made in four assay systems which measure inhibition of the action of LHRH on isolated rat pituitaries in vitro, inhibition of the release of the LH induced by LHRH in vivo in adult male rats and adult male chimpanzees, and inhibition of spontaneous ovulation in cycling female rats. Only a partial correlation was observed between the in vitro and in vivo assays. Currently, the most potent LHRH analog antagonists in the present study were based on a 1,2,3,6-tetra-substituted LHRH sequence. The analogs [D less than Glu1,DPhe2,DTrp3,DTrp6]-LHRH, Ac-[Pro1,DPhe2,DTrp3,DTrp6]LHRH and [(Glu-Pro)1, dphe2,DTrp3,DTrp6]LHRH completely inhibited spontaneous ovulation in cycling rats at a dosage of 200 microgram/rat, sc. The most potent inhibitors of ovulation were always very potent in vitro, but other analogs having identical in vitro activities had little or no antiovulatory activity even at substantially higher dosages. The analogs inhibited the action of LHRH in the rat more easily than in the chimpanzee. Twelve of 13 analogs at the analog to LHRH ratio of 100:1 significantly inhibited the LH response, while only 5 of 9 of these same analogs inhibited the LH response in the chimpanzee at the analog to LHRH ratio of 333:1. Only 1 of 8 analogs at a high dosage inhibited the binding of labeled LH to the gonadal LH receptor in vitro. The inability of the less polar (cyclopentane carboxylic acid) analogs to inhibit ovulation could be explained, at least partially, in terms of impaired absorption sc. Although the cyclopentane carboxylic acid analogs effectively inhibited the action of LHRH in vitro and, when given iv in vivo, they were not effective in blocking the LHRH-stimulated LH response in adult male rats when given sc, which is the mode of administration of the antiovulatory assay, suggesting the importance of the route of administration.
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Hormona Folículo Estimulante/metabolismo , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Luteinizante/metabolismo , Hipófisis/metabolismo , Animales , Femenino , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Técnicas In Vitro , Hormona Luteinizante/sangre , Ovulación/efectos de los fármacos , Pan troglodytes , Ratas , Especificidad de la Especie , Relación Estructura-ActividadRESUMEN
BACKGROUND: The goal of this study was to evaluate the role of genetic variation in the coding sequence of tryptophan hydroxylase (TPH) in the pathogenesis of several psychiatric diseases in which altered serotonin function has been implicated: bipolar affective disorder (BP), obsessive-compulsive disorder (OCD), anorexia nervosa (AN), seasonal affective disorder (SAD), panic disorder (PD), and alcoholism (Alc). METHODS: Ninety-three percent of the TPH coding sequence was screened by polymerase chain reaction single-strand conformation polymorphism (SSCP) for DNA sequence variations in 128 AN, 88 OCD, 72 SAD, 45 PD, and 36 BP patients and 142 normal volunteers. Also included in the screening were 61 Alc randomly selected from a Finnish alcoholic population in which an association of a TPH intron 7 polymorphism with suicidality was previously observed. Polymorphisms detected by SSCP were characterized by DNA sequencing and by allele-specific restriction enzyme digestion. Genotyping was then performed in 34 Finnish alcoholic suicide attempters. RESULTS: A rare silent mutation was identified in exon 10 and is designated T1095C. The C1095 allele was found in 1 OCD and in 2 AN subjects; all 3 individuals were heterozygous (C1095/T1095) for the variant allele. No association was observed between this TPH T1095C variant with either OCD, AN, Alc, or suicidality. CONCLUSION: These results suggest that the coding sequence of the TPH gene does not contain abundant variants, and may not play a major role in vulnerability to several psychopathologies in which reduced serotonin turnover has been implicated.