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BACKGROUND: Early phase clinical trials in Oncology represent a subspecialised area where UK patient selection is influenced by access to Experimental Cancer Medicine Centres (ECMCs). Equity of access with respect to social determinants of health (SDoH) were explored for two major ECMCs. METHODS: A retrospective cohort study including all referrals to Newcastle and Manchester ECMCs in 2021 was completed. Consent to screening or pre-screening was stratified against SDoH characteristics, including: Index of Multiple Deprivation (IMD) decile, ethnicity and distance to centre. RESULTS: 1243 patients were referred for trials. IMD quintile 1 (most deprived) patients had reduced likelihood of referral compared to expected population models (OR, 0.67; 95% CI: 0.55 to 0.80, p = <0.0001). IMD quintile 5 (least deprived) had increased likelihood of referral (OR, 1.46; 95% CI: 1.17 to 1.82, p = 0.0007). Living beyond median distance from Manchester reduced the likelihood of consenting to trials (OR, 0.72; 95% CI: 0.55 to 0.94, p = 0.015). Ethnicity data represented a White British propensity. CONCLUSIONS: Inequalities in socioeconomic and geographic factors influence referral and enrolment to early phase clinical trials in Northern England. This has implications for equity of access and generalisability of trial results internationally and warrants further study.
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Determinantes Sociales de la Salud , Humanos , Inglaterra/epidemiología , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Neoplasias/epidemiología , Neoplasias/terapia , Anciano , Disparidades en Atención de Salud/estadística & datos numéricos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Selección de Paciente , Factores Socioeconómicos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , AdultoRESUMEN
A case is described in which the short-acting glycoprotein IIb/IIIa receptor antagonist tirofiban was used in combination with heparin, aspirin and prasugrel to successfully treat extensive intracoronary thrombus in a delayed presentation STEMI, illustrating the utility of this approach.
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Abciximab , Aspirina/administración & dosificación , Trombosis Coronaria/tratamiento farmacológico , Heparina/administración & dosificación , Clorhidrato de Prasugrel/administración & dosificación , Infarto del Miocardio con Elevación del ST/tratamiento farmacológico , Tirofibán/administración & dosificación , Anciano , Trombosis Coronaria/complicaciones , Humanos , Masculino , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Infarto del Miocardio con Elevación del ST/complicacionesRESUMEN
We report on the design and testing of a multiwavelength interferometry system for the Orion laser facility based upon the use of self-path matching Wollaston prisms. The use of UV corrected achromatic optics allows for both easy alignment with an eye-safe light source and small (â¼ millimeter) offsets to the focal lengths between different operational wavelengths. Interferograms are demonstrated at wavelengths corresponding to first, second, and fourth harmonics of a 1054 nm Nd:glass probe beam. Example data confirms the broadband achromatic capability of the imaging system with operation from the UV (263 nm) to visible (527 nm) and demonstrates that features as small as 5 µm can be resolved for object sizes of 15 by 10 mm. Results are also shown for an off-harmonic wavelength that will underpin a future capability. The primary optics package is accommodated inside the footprint of a ten-inch manipulator to allow the system to be deployed from a multitude of viewing angles inside the 4 m diameter Orion target chamber.
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BACKGROUND: Vernonia divaricata is one of five endemic Vernonia species of Jamaica. The ethno-medicinal uses of other species have been established, however, scientific validation of this species has not yet been done and as such this paper is aimed at identifying the anti-cancer activity of V divaricata against leukaemia, breast and prostate cancer cell lines. METHODS: Leaves and stems of V divaricata were dried and milled into powder. The crude hexane and methanol extracts of the leaves and stems were obtained and bio-assayed using WST-1 cell proliferation assay against leukaemia, breast and prostate cancer cell lines. RESULTS: The crude hexane and methanol extracts of V divaricata were able to significantly retard the growth of the MCF-7 (breast), HL-60 (leukaemia) and the PC-3 (prostate) cancer cell lines. The crude methanol extract of the stem was the strongest, exhibiting anti-proliferation activity with IC50 values of 10.14, 12.63 and 9.894 µg/ml for the HL-60, MCF-7 and PC-3 cancer cell lines, respectively, with the most potent toward prostate cancer. CONCLUSION: The medicinal use of V divaricata as an anti-cancer agent was corroborated as the crude hexane and methanol extracts demonstrated potent anti-proliferation activity and as such hold potential for further research and development into a drug to prevent or treat various cancers.
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Estenosis de la Válvula Aórtica/cirugía , Dolor en el Pecho/complicaciones , Depresión/epidemiología , Vigilancia de la Población , Autoinforme , Centros de Atención Terciaria , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Anciano , Estenosis de la Válvula Aórtica/diagnóstico , Dolor en el Pecho/epidemiología , Depresión/etiología , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Nueva Zelanda/epidemiología , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: Tillandsia recurvata, also commonly known as Ball Moss, is endemic to Jamaica and some parts of the Caribbean and South America. The plant, despite being reported to be used in folk medicine, had not previously been evaluated for its anti-cancer potential. The aim of this study was to evaluate the anti-cancer activity ofBall Moss. METHODS: The anti-proliferation activity of the crude methanolic extract of the T recurvata was evaluated in vitro in five different histogenic cancer cell lines (prostate cancer - PC-3, breast cancer Kaposi sarcoma, B-16 melanoma and a B-cell lymphoma from a transgenic mouse strain) using the trypan blue assay. The crude extract was also evaluated in vivo in tumour-bearing mice. Immunohistochemistry staining with Apoptag was used for histology and determination of apoptosis. RESULTS: The crude methanolic extract of T recurvata demonstrated anti-proliferation activity against all the cell lines, killing > 50% of the cells at a concentration of 2.5 microg/ml. Kaposi sarcoma xenograft tumours were inhibited by up to 75% compared to control in the in vivo study (p < 0.05). There was evidence of DNA fragmentation and a decrease in cell viability on histological studies. The methanolic extract showed no toxic effect in the mice at a dose of 200 mg/kg. CONCLUSIONS: Our data suggest that T recurvata has great potential as an anti-cancer agent and that one of its mechanisms of cell kill and tumour inhibition is by the induction of apoptosis.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/farmacología , Tillandsia , Animales , Neoplasias de la Mama , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN/efectos de los fármacos , Femenino , Humanos , Jamaica , Linfoma de Células B , Masculino , Melanoma , Ratones , Neoplasias de la Próstata , Sarcoma de Kaposi , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
Early growth response factor-1 (Egr-1) binds to the promoters of many genes whose products influence cell movement and replication in the artery wall. Here we targeted Egr-1 using a new class of DNA-based enzyme that specifically cleaved Egr-1 mRNA, blocked induction of Egr-1 protein, and inhibited cell proliferation and wound repair in culture. The DNA enzyme also inhibited Egr-1 induction and neointima formation after balloon injury to the rat carotid artery wall. These findings demonstrate the utility of DNA enzymes as biological tools to delineate the specific functions of a given gene, and implicate catalytic nucleic acid molecules composed entirely of DNA as potential therapeutic agents.
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División Celular/genética , ADN de Cadena Simple/metabolismo , Proteínas de Unión al ADN/genética , Proteínas Inmediatas-Precoces , Músculo Liso Vascular/citología , ARN Mensajero/metabolismo , Factores de Transcripción/genética , Animales , Secuencia de Bases , Sangre , Células Cultivadas , Proteínas de Unión al ADN/metabolismo , Proteína 1 de la Respuesta de Crecimiento Precoz , Regulación Enzimológica de la Expresión Génica , Humanos , Hidrólisis , Inmunohistoquímica , Músculo Liso Vascular/lesiones , ARN Mensajero/genética , Ratas , Factores de Transcripción/metabolismoRESUMEN
Gene silencing techniques are gaining increasing popularity in the literature, both as a tool for unravelling gene function and to potentially deliver therapeutic benefit, especially in the context of cardiovascular disease. Gene-specific catalytic DNA molecules, or DNAzymes, have shown promise in ameliorating the effects of myocardial ischaemia reperfusion injury and in-stent restenosis in various animal models, demonstrating that these agents may be useful in a clinical setting. A review of the recent advances in the use of DNAzymes in treating cardiovascular disease is therefore essential given the increasing clinical burden of cardiovascular disease worldwide. We have thus sought to firstly provide background into the construct and mechanism of action of DNAzymes, with a discussion of recent improvements in design. Secondly, we have examined the effects of DNAzyme-mediated gene inhibition in in vitro studies of both endothelial and smooth muscle migration and proliferation, as well as in vivo models of acute myocardial infraction and neointima formation. Lastly we compare DNAzymes with other gene silencing tools and discuss issues involved in successfully delivering these drugs in a clinical setting.
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Enfermedades Cardiovasculares/terapia , ADN Catalítico/metabolismo , Marcación de Gen/métodos , Animales , Enfermedades Cardiovasculares/enzimología , Silenciador del Gen , Terapia Genética/métodos , HumanosRESUMEN
BACKGROUND: Mice lacking plasminogen (PG-/-) require alternative pathways of fibrinolysis for survival. This may depend on polymorphonuclear leukocytes (PMN) that can clear soluble and insoluble fibrin(ogen) through PG-independent processes. Our objective was to demonstrate that PMNs from PG-/- mice exhibit increased Mac-1 dependent phagocytic activity, which may explain their increased fibrin(ogen)lytic activity compared with wild type (PG+/+) mice. METHODS: Phagocytic activity of PMNs from PG-/- and PG+/+ mice was compared following exposure to Staphylococcus aureus (S. aureus) particles and the expression of Mac-1 was assessed in parallel by flow cytometric analysis. Resistance to phorbol-12-myristate-13-acetate (PMA)-induced cell death was compared between PMNs from the different genotypes. RESULTS: Stimulation of PG-/- PMNs by opsonized S. aureus diluted in PG-/- plasma significantly increased phagocytosis (15-fold) compared with stimulation of PG+/+ PMNs in PG+/+ plasma. Incubation of PG-/- PMNs with PG+/+ plasma (control) or PG-/- plasma supplemented with human PG inhibited this increased phagocytic activity. Mac-1 cell surface density increased 6.2+/-1.0-fold in PG-/- PMNs versus 2.9+/-0.6-fold in PG+/+ PMNs (P < 0.01) indicating that Mac-1 may be associated with increased phagocytic activity. Supporting this, treatment of PG-/- PMNs with an anti-Mac-1 antibody in PG-/- plasma inhibited phagocytic activity. In addition, physiologic PG blocked Mac-1 accessibility at the surface of PMNs. Addition of PMA resulted in 33% death of PMNs from PG-/- mice versus 68% in PG+/+ controls (P < 0.001). CONCLUSIONS: PMNs from PG-/- mice exhibit a Mac-1 dependent increase in phagocytic activity that is suppressed with human PG, an anti-Mac-1 antibody or the plasma from PG+/+ mice. The propensity for PMNs from PG-/- mice to be activated in response to PMA together with their relative resistance to PMA-toxicity may contribute to increased PMN half-life and enhanced fibrin(ogen) clearance in the setting of PG deficiency.
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Neutrófilos/fisiología , Fagocitosis/fisiología , Plasminógeno/deficiencia , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Apoptosis/fisiología , Secuencia de Bases , Cartilla de ADN/genética , Femenino , Fibrinólisis/fisiología , Antígeno de Macrófago-1/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Fagocitosis/efectos de los fármacos , Fagocitosis/genética , Plasminógeno/genética , Plasminógeno/fisiología , Staphylococcus aureus/inmunología , Acetato de Tetradecanoilforbol/farmacologíaRESUMEN
CONTEXT: Patients with elevated PTH and consistently normal serum calcium levels, in whom secondary causes of hyperparathyroidism have been excluded, may represent the earliest presentation of primary hyperparathyroidism (PHPT). OBJECTIVE: The objective of the study was to characterize patients with normocalcemic PHPT referred to a bone disease unit. DESIGN: This was a longitudinal cohort study. SETTING: Ambulatory patients were referred to the metabolic bone disease unit. PATIENTS: The study population included 37 patients [aged 58 yr, range 32-78; 95% female; serum calcium, 9.4 +/- 0.1 (sem) mg/dl (2.3 +/- 0.02 mmol/liter), reference range, 8.5-10.4 (2.1-2.6 mmol/liter); PTH, 93 +/- 5 pg/ml]. INTERVENTIONS: Interventions included yearly (median 3 yr; range 1-8 yr) physical examination, biochemical indices, and bone mineral density (BMD). MAIN OUTCOME MEASURES: We measured the development of features of PHPT. RESULTS: Evaluation for classical features of PHPT revealed a history of kidney stones in five (14%), fragility fractures in four (11%), and osteoporosis in 57% [spine (34%), hip (38%), and/or distal one third radius (28%)]. BMD did not show preferential bone loss at the distal one third radius (T scores: spine, -2.00 +/- 0.25; hip, -1.84 +/- 0.18; one third radius, -1.74 +/- 0.22). Further signs of PHPT developed in 40% (seven hypercalcemia; one kidney stone; one fracture; two marked hypercalciuria; six had >10% BMD loss at one or more site(s) including four patients developing World Health Organization criteria for osteoporosis). Seven patients (three hypercalcemic, four persistently normocalcemic) underwent successful parathyroidectomy. CONCLUSIONS: Patients seen in a referral center with normocalcemic hyperparathyroidism have more substantial skeletal involvement than is typical in PHPT and develop more features and complications over time. These patients may represent the earliest form of symptomatic, rather than asymptomatic, PHPT.
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Calcio/sangre , Hiperparatiroidismo Primario/sangre , Adulto , Anciano , Densidad Ósea , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Hiperparatiroidismo Primario/cirugía , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Paratiroidectomía , Fenotipo , Cintigrafía , Radiofármacos , Tecnecio Tc 99m SestamibiRESUMEN
BACKGROUND AND AIM: The transcription factor and immediate-early gene Egr-1 is widely viewed as a key upstream activator in a variety of settings within cardiovascular pathobiology. The role that Egr-1 plays in myocardial ischemia-reperfusion (IR) injury is unknown. We hypothesized that Egr-1 upregulation is of pathophysiologic importance in myocardial IR injury. METHODS AND RESOURCES: First, abrogation of Egr-1 mRNA upregulation using Egr-1 targeting DNAzymes in a rat cardiomyocyte in vitro model was demonstrated. Egr-1 mRNA and protein upregulation following myocardial IR in rats were then selectively suppressed by locally delivered DNAzyme. Furthermore, myocardial neutrophil infiltration, intercellular adhesion molecule 1 mRNA and protein expression, and myocardial infarct size were all attenuated in DNAzyme-treated animals. CONCLUSIONS: These data support the hypothesis that Egr-1 is a key contributor to myocardial IR injury, and that Egr-1 targeting strategies have therapeutic potential in this context.
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ADN Catalítico/uso terapéutico , Proteína 1 de la Respuesta de Crecimiento Precoz/fisiología , Infarto del Miocardio/prevención & control , Daño por Reperfusión/tratamiento farmacológico , Animales , Movimiento Celular/efectos de los fármacos , ADN Catalítico/administración & dosificación , Proteína 1 de la Respuesta de Crecimiento Precoz/efectos de los fármacos , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Molécula 1 de Adhesión Intercelular/genética , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/etiología , Miocitos Cardíacos/patología , Neutrófilos/citología , ARN Mensajero/efectos de los fármacos , Ratas , Daño por Reperfusión/complicaciones , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genéticaRESUMEN
Early growth response factor-1 (Egr-1) controls the expression of a growing number of genes involved in the pathogenesis of atherosclerosis and postangioplasty restenosis. Egr-1 is activated by diverse proatherogenic stimuli. As such, this transcription factor represents a key molecular target in efforts to control vascular lesion formation in humans. In this study, we have generated DNAzymes targeting specific sequences in human EGR-1 mRNA. These molecules cleave in vitro transcribed EGR-1 mRNA efficiently at preselected sites, inhibit EGR-1 protein expression in human aortic smooth muscle cells, block serum-inducible cell proliferation, and abrogate cellular regrowth after mechanical injury in vitro. These DNAzymes also selectively inhibit EGR-1 expression and proliferation of porcine arterial smooth muscle cells and reduce intimal thickening after stenting pig coronary arteries in vivo. These findings demonstrate that endoluminally delivered DNAzymes targeting EGR-1 may serve as inhibitors of in-stent restenosis.
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Vasos Coronarios/metabolismo , ADN Catalítico/farmacología , Proteínas de Unión al ADN/metabolismo , Oclusión de Injerto Vascular/metabolismo , Oclusión de Injerto Vascular/prevención & control , Proteínas Inmediatas-Precoces , Factores de Transcripción/metabolismo , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/patología , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteína 1 de la Respuesta de Crecimiento Precoz , Regulación de la Expresión Génica/efectos de los fármacos , Oclusión de Injerto Vascular/patología , Humanos , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/metabolismo , Porcinos , Factores de Transcripción/genética , Túnica Íntima/efectos de los fármacos , Túnica Íntima/metabolismo , Túnica Íntima/patologíaRESUMEN
Dibenzyl trisulfide (DTS) is the major active ingredient expressed in Petiveria alliacea L., a shrub widely used for a range of conditions, such as, arthritis, asthma and cancer. Given its use alone and concomitantly with prescription medicines, we undertook to investigate its impact on the activities of important drug metabolizing enzymes, the cytochromes P450 (CYP), a key family of enzymes involved in many adverse drug reactions. DTS and seven standardized extracts from the plant were assessed for their impact on the activities of CYPs 1A2, 2C19, 2C9, 2D6 and 3A4 on a fluorometric assay. DTS revealed significant impact against the activities of CYPs 1A2, 2C19 and 3A4 with IC50 values of 1.9, 4.0 and 3.2µM, respectively, which are equivalent to known standard inhibitors of these enzymes (furafylline, and tranylcypromine), and the most potent interaction with CYP1A2 displayed irreversible enzyme kinetics. The root extract, drawn with 96% ethanol (containing 2.4% DTS), displayed IC50 values of 5.6, 3.9 and 4.2µg/mL respectively, against the same isoforms, CYPs 1A2, 2C19 and 3A4. These investigations identify DTS as a valuable CYP inhibitor and P. alliacea as a candidate plant worthy of clinical trials to confirm the conclusions that extracts yielding high DTS may lead to clinically relevant drug interactions, whilst extracts yielding low levels of DTS, such as aqueous extracts, are unlikely to cause adverse herb-drug interactions.
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Compuestos de Bencilo/farmacología , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Interacciones de Hierba-Droga , Phytolaccaceae/química , Extractos Vegetales/farmacología , Sulfuros/farmacología , HumanosRESUMEN
Atherosclerotic cardiovascular disease remains the leading cause of death in the industrialized world. Most cardiovascular deaths result from acute coronary syndromes, including unstable angina pectoris and acute myocardial infarction. Coronary syndromes often arise from acute coronary thrombosis, itself commonly a result of disruption or rupture of the fibrous cap of a lipid-laden atherosclerotic plaque. Despite this huge clinical burden of atherosclerotic plaque instability, our understanding of the molecular mechanisms mediating atherosclerotic plaque disruption and rupture, at a cellular level, remains limited. Placed in a clinical context, this review discusses our current understanding of the molecular basis for atherosclerotic plaque instability, with particular emphasis on the process of apoptosis-or programmed cell death-seen increasingly as playing a key role in a number of cell types within the vessel wall.
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Apoptosis , Arterias/patología , Arteriosclerosis/patología , Arteriosclerosis/complicaciones , Endotelio Vascular/patología , Humanos , Macrófagos/patología , Músculo Liso Vascular/patologíaRESUMEN
The last decade has seen a number of important advances in the use of animal models of atherosclerosis progression. Small animal models, particularly mouse knockouts and rabbit models, are finding increasing use. This review discusses those models of particular research utility, highlights their advantages and limitations, and specifically addresses methodologies and current developments, in what is a rapidly changing field.
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Aterosclerosis/prevención & control , Investigación Biomédica/métodos , Modelos Animales de Enfermedad , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/patología , Investigación Biomédica/tendencias , Progresión de la Enfermedad , HumanosRESUMEN
BACKGROUND: Inadequate treatments are reported for depressed patients cared for by primary care physicians (PCPs). Providing feedback and evidence-based treatment recommendations for depression to PCPs via electronic medical record improves the quality of interventions. METHODS: Patients presenting to an urban academically affiliated primary care practice were screened for major depression with the Primary Care Evaluation of Mental Disorders (PRIME-MD). During 20-month period, 212 patients met protocol-eligibility criteria and completed a baseline interview. They were cared for by 16 board-certified internists, who were electronically informed of their patients' diagnoses, and randomized to 1 of 3 methods of exposure to guideline-based advice for treating depression (active, passive, and usual care). Ensuing treatment patterns were assessed by medical chart review and by patient self-report at baseline and 3 months. RESULTS: Median time for PCP response to the electronic message regarding the patient's depression diagnosis was 1 day (range, 1-95 days). Three days after notification, 120 (65%) of 186 PCP responses indicated agreement with the diagnosis, 24 (13%) indicated disagreement, and 42 (23%) indicated uncertainty. Primary care physicians who agreed with the diagnoses sooner were more likely to make a medical chart notation of depression, begin antidepressant medication therapy, or refer to a mental health specialist (P<.001). There were no differences in the agreement rate or treatments provided across guideline exposure conditions. CONCLUSIONS: Electronic feedback of the diagnosis of major depression can affect PCP initial management of the disorder. Further study is necessary to determine whether this strategy, combined with delivery of treatment recommendations, can improve clinical outcomes in routine practice.
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Trastorno Depresivo/diagnóstico , Trastorno Depresivo/terapia , Sistemas de Registros Médicos Computarizados , Médicos de Familia , Adolescente , Adulto , Medicina Basada en la Evidencia , Femenino , Adhesión a Directriz , Humanos , Medicina Interna , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Encuestas y CuestionariosRESUMEN
We report on the design, construction, and characterisation of a new class of in-vacuo optical levitation trap optimised for use in high-intensity, high-energy laser interaction experiments. The system uses a focused, vertically propagating continuous wave laser beam to capture and manipulate micro-targets by photon momentum transfer at much longer working distances than commonly used by optical tweezer systems. A high speed (10 kHz) optical imaging and signal acquisition system was implemented for tracking the levitated droplets position and dynamic behaviour under atmospheric and vacuum conditions, with ±5 µm spatial resolution. Optical trapping of 10 ± 4 µm oil droplets in vacuum was demonstrated, over timescales of >1 h at extended distances of â¼40 mm from the final focusing optic. The stability of the levitated droplet was such that it would stay in alignment with a â¼7 µm irradiating beam focal spot for up to 5 min without the need for re-adjustment. The performance of the trap was assessed in a series of high-intensity (10(17) W cm(-2)) laser experiments that measured the X-ray source size and inferred free-electron temperature of a single isolated droplet target, along with a measurement of the emitted radio-frequency pulse. These initial tests demonstrated the use of optically levitated microdroplets as a robust target platform for further high-intensity laser interaction and point source studies.
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A recent controversial report suggests that the nocturnal inhibitor of Rubisco, 2-carboxy-D-arabinitol 1-phosphate (CAIP), does not bind to Rubisco in vivo and therefore that CA1P has no physiological relevance to photosynthetic regulation. It is now proved that a direct rapid assay can be used to distinguish between Rubisco-bound and free CA1P, as postulated in the controversial report. Application of this direct assay demonstrates that CA1P is bound to Rubisco in vivo in dark-adapted leaves. Furthermore, CA1P is shown to be in the chloroplasts of mesophyll cells. Thus, CA1P does play a physiological role in the regulation of Rubisco.