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1.
PLoS One ; 16(4): e0249297, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33909630

RESUMEN

BACKGROUND: Prognosis in Palliative care Study (PiPS) models predict survival probabilities in advanced cancer. PiPS-A (clinical observations only) and PiPS-B (additionally requiring blood results) consist of 14- and 56-day models (PiPS-A14; PiPS-A56; PiPS-B14; PiPS-B56) to create survival risk categories: days, weeks, months. The primary aim was to compare PIPS-B risk categories against agreed multi-professional estimates of survival (AMPES) and to validate PiPS-A and PiPS-B. Secondary aims were to assess acceptability of PiPS to patients, caregivers and health professionals (HPs). METHODS AND FINDINGS: A national, multi-centre, prospective, observational, cohort study with nested qualitative sub-study using interviews with patients, caregivers and HPs. Validation study participants were adults with incurable cancer; with or without capacity; recently referred to community, hospital and hospice palliative care services across England and Wales. Sub-study participants were patients, caregivers and HPs. 1833 participants were recruited. PiPS-B risk categories were as accurate as AMPES [PiPS-B accuracy (910/1484; 61%); AMPES (914/1484; 61%); p = 0.851]. PiPS-B14 discrimination (C-statistic 0.837) and PiPS-B56 (0.810) were excellent. PiPS-B14 predictions were too high in the 57-74% risk group (Calibration-in-the-large [CiL] -0.202; Calibration slope [CS] 0.840). PiPS-B56 was well-calibrated (CiL 0.152; CS 0.914). PiPS-A risk categories were less accurate than AMPES (p<0.001). PiPS-A14 (C-statistic 0.825; CiL -0.037; CS 0.981) and PiPS-A56 (C-statistic 0.776; CiL 0.109; CS 0.946) had excellent or reasonably good discrimination and calibration. Interviewed patients (n = 29) and caregivers (n = 20) wanted prognostic information and considered that PiPS may aid communication. HPs (n = 32) found PiPS user-friendly and considered risk categories potentially helpful for decision-making. The need for a blood test for PiPS-B was considered a limitation. CONCLUSIONS: PiPS-B risk categories are as accurate as AMPES made by experienced doctors and nurses. PiPS-A categories are less accurate. Patients, carers and HPs regard PiPS as potentially helpful in clinical practice. STUDY REGISTRATION: ISRCTN13688211.


Asunto(s)
Cuidadores/psicología , Personal de Salud/psicología , Neoplasias/patología , Cuidados Paliativos , Pacientes/psicología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Pronóstico , Estudios Prospectivos , Factores de Riesgo
2.
Prostate Cancer Prostatic Dis ; 12(1): 72-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18475286

RESUMEN

Investigator-derived quality of life (QoL) instruments such as the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire do not allow participants to weight the relative importance of QoL domains. We investigated the effect of allowing patients the ability to weight the relative importance of the five areas included in the FACT-P (Physical, Social, Emotional and Functional well-being, and Additional concerns). Patients (n=150) completed the FACT-P and gauged the relative importance of each QoL domain using a direct-weighting approach. This was then used to provide an adjusted Hybrid QoL score. Patients also completed a Visual Analogue Scale. Patients considered Social well-being to be the most important domain and Additional concerns to be the least important. When patient weightings were taken into account overall QoL scores increased. The validity of the Hybrid score was supported by its ability to distinguish between patients with metastatic and locoregional disease and its ability to detect expected decreases in global QoL over time. Application of the direct-weighting approach to the FACT-P allows assessments to more accurately reflect individual QoL. Unadjusted QoL scores may lead researchers to incorrectly estimate the true QoL of respondents.


Asunto(s)
Neoplasias de la Próstata/psicología , Calidad de Vida , Encuestas y Cuestionarios , Humanos , Masculino , Neoplasias de la Próstata/patología
3.
Prostate Cancer Prostatic Dis ; 11(4): 390-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18427572

RESUMEN

Prostate cancer can have diverse effects on patients' quality of life (QoL). Standard QoL questionnaires do not address all of the concerns expressed by such patients. The primary purpose of this study was to identify those issues with the greatest influence on the QoL of patients with prostate cancer. A secondary aim was to compare the performance of the Schedule for the Evaluation of Individual Quality of Life-Direct Weighting (SEIQoL-DW) semi-structured interview with the Functional Assessment of Cancer Therapy-Prostate questionnaire (FACT-P). A mixed population of patients with prostate cancer (including those with localized and metastatic disease) completed the SEIQoL-DW and the FACT-P. The SEIQoL-DW was satisfactorily completed by 180 patients, including 93 patients with metastatic disease. Patients identified 144 separate QoL concerns, and these were then independently grouped by three of the authors into 13 distinct themes. The most frequently identified themes were 'leisure and hobbies', 'family' and 'health'. The themes that patients considered to be the most important were 'partner/spouse', 'family' and 'health'. Patients were most satisfied with their QoL in the domains of 'family', 'partner/spouse' and 'friends'. They were least satisfied with 'sexuality', 'mobility' and 'psychological factors'. Patients with metastatic disease rated their QoL significantly (P<0.0001) lower than other patients using the FACT-P, but not using the SEIQoL-DW (P=0.07). Patients with prostate cancer identified numerous QoL concerns that are not included (or are underrepresented) in standard health-related QoL questionnaires such as the FACT-P. Health-related QoL questionnaires may underestimate the QoL of patients with metastatic disease.


Asunto(s)
Neoplasias de la Próstata , Calidad de Vida , Humanos , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Encuestas y Cuestionarios
4.
Ann Oncol ; 18(8): 1395-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17513884

RESUMEN

BACKGROUND: The vitamin B(12)/C-reactive protein Index (BCI) has been proposed as a prognostic indicator in patients with advanced cancer. The purpose of this study was to confirm the utility of the BCI in palliative care patients. PATIENTS AND METHODS: Patients with advanced cancer provided a blood specimen for analysis. Demographic and disease-related variables were recorded. Patients were followed up for at least 90 days or until death. RESULTS: Patients (n = 329) were divided into three groups according to their BCI score. Patients in group 3 (BCI >40,000; median survival 29 days) had a significantly (P < 0.01) worse survival than patients in group 2 (BCI 10,001-40,000; median survival 43 days) and patients in group 1 (BCI < or =10,000; median survival 71 days). However, patients in group 1 did not have a significantly better prognosis than those in group 2 (P = 0.091). The point estimates for 90-day mortality for each of the three risk groups were different from the figures previously reported during the development phase of the BCI (group 1, 58.9% versus 47.2%; group 2, 64.0 versus 72.5%; group 3, 78.9% versus 90.6%). CONCLUSIONS: An elevated BCI (>40,000) predicts poor survival in patients with advanced cancer.


Asunto(s)
Proteína C-Reactiva/análisis , Neoplasias/sangre , Neoplasias/mortalidad , Vitamina B 12/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Cuidados Paliativos , Valor Predictivo de las Pruebas , Pronóstico
5.
Ann Oncol ; 18(6): 971-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17043092

RESUMEN

BACKGROUND: Patients with advanced cancer and their carers frequently wish to know how long they can expect to live. Improved prognostication would enable patients and their carers to be better prepared for their impending death, and would allow clinicians to make better informed decisions about place of care. However, clinician estimates of survival are inaccurate and systematically overoptimistic. Recently, attempts have been made to improve upon clinician estimates of survival by devising prognostic scales incorporating clinical information with biochemical and haematological results. DESIGN: A descriptive and critical review of palliative prognostic scales, on the basis of the recommendations of the European Association of Palliative Care prognosis working group (2005) supplemented by an Ovid Medline search 1966-March 2006 using the key words 'prognosis', 'neoplasms', 'palliative care' and 'terminal care'. RESULTS: This paper reviews the advantages and limitations of the palliative prognostic score, the palliative prognostic index, the Chuang prognostic scale, the terminal cancer prognostic score and the poor prognostic indicator. CONCLUSIONS: All the currently available prognostic scales have limitations, but nonetheless offer an improvement on unadjusted clinician estimates of survival. Further research is required to systematically develop a prognostic scale on the basis of all the known prognostic variables in patients with advanced cancer.


Asunto(s)
Planificación Anticipada de Atención , Neoplasias/terapia , Toma de Decisiones , Humanos , Consentimiento Informado , Neoplasias/mortalidad , Pronóstico , Análisis de Supervivencia
6.
Biochem Biophys Res Commun ; 295(5): 1150-5, 2002 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-12135614

RESUMEN

We used a novel perfusion system to expose cultured human umbilical vein endothelial cells (HUVEC) to water-soluble components of cigarette smoke and study subsequent adhesion of flowing neutrophils. Neutrophils did not bind to HUVEC immediately after it had been exposed to cigarette smoke, but many adhered 90-150 min after exposure. The effect was reduced if the exposed medium was made serum-free, but this reduction was partially reversed if low density lipoprotein was added. Treatment of smoke-exposed HUVEC with antibodies against E-selectin or P-selectin reduced adhesion by approximately 50% or 75%, respectively; a combination of both antibodies essentially abolished adhesion. Enzyme-linked immunosorbent assay confirmed that exposure to smoke caused HUVEC to upregulate surface expression of E- and P-selectin. Thus, water-soluble constituent(s) of cigarette smoke cause efficient selectin-mediated capture of flowing neutrophils. This pro-inflammatory response may contribute to pathology associated with smoking, especially in tissues remote from the lung.


Asunto(s)
Adhesión Celular/fisiología , Endotelio Vascular/fisiopatología , Neutrófilos/fisiología , Selectinas/fisiología , Fumar/patología , Medios de Cultivo , Humanos , Técnicas In Vitro , Perfusión
7.
J Comp Physiol B ; 171(2): 135-43, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11302530

RESUMEN

Male rats and hamsters were exposed to a progressively lower air temperature and shorter photoperiod to simulate the onset of winter. Normothermic hamsters had a higher haematological oxygen carrying capacity (OCC) and coagulability (shorter prothrombin time and activated partial thromboplastin time) than rats. Cold acclimation significantly increased the OCC of rats, which parallels an increased metabolic rate, while no differences were observed in hamsters. Red cell transit time through filters was faster in the acclimated rats but not in hamsters, reflecting the lower mean cell volume due to a decreased rate of clearance from the circulation. Platelet counts were significantly lower in both cold-acclimated rats and hamsters, and there was a significant leucopenia in rats, which would reduce the degree of microvascular blockade. Whole blood viscosity, plasma viscosity, and serum osmolarity showed little change in either species. However, whole blood viscosity was significantly lower in cold-acclimated hamsters than control hamsters at the lowest shear rate tested (0.95 s(-1)). Interestingly, plasma viscosity and serum osmolarity were significantly lower in hamsters exposed to low temperatures for a shorter period (4 weeks), and may reflect the development of a reduced coagulability. These data suggest that blood composition in hamsters contributes to an innate tolerance of low temperatures, maintaining tissue perfusion under hypothermic conditions and aiding arousal from hibernation.


Asunto(s)
Aclimatación/fisiología , Viscosidad Sanguínea/fisiología , Frío , Deformación Eritrocítica/fisiología , Consumo de Oxígeno/fisiología , Animales , Coagulación Sanguínea/fisiología , Cricetinae , Hibernación/fisiología , Masculino , Mesocricetus , Ratas , Ratas Wistar , Especificidad de la Especie
8.
Br J Haematol ; 105(2): 514-22, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10233431

RESUMEN

Immobilized activated platelets present P-selectin and efficiently capture flowing neutrophils. We investigated how the treatment of the platelets affected whether adherent neutrophils rolled continuously or became immobilized. Washed platelets were maintained in a 'resting' state by Ca++ chelation, prostacyclin and theophylline. When these platelets were adhered to glass that had been coated with aminopropyltriethoxysilane (APES) they retained discoidal morphology. Compared to a confluent surface of spread platelets prepared by allowing heparinized platelet-rich plasma to settle on APES-glass, 'resting' platelets captured far fewer flowing neutrophils, which rolled rapidly. However, if neutrophils were perfused along with thrombin (>/= 0.2 U/ml), then the resting platelets rapidly changed shape, neutrophil binding increased markedly, rolling velocity decreased, and 40-70% of the neutrophils were immobilized via beta2-integrins. Similar effects could be induced using ADP perfused with the neutrophils. Thrombin did not itself activate neutrophils, and stationary adhesion could also be induced if platelets were treated with thrombin before addition of neutrophils. After thrombin treatment of platelets, rolling adhesion was only fully re-established after a prolonged period of washout. Thus, platelets presented a stable surface-bound agent able to activate neutrophils. Blockade of platelet-activating factor receptor, leukotriene B4 receptor, or CXC-chemokine receptor 1 (CXCR1) on neutrophils did not inhibit conversion from rolling to stationary adhesion, but blockade of CXCR2 maintained a higher proportion of rolling adhesion. Thus, platelets attached to damaged vessels may capture flowing neutrophils, but the stability of neutrophil deposition will depend on the scale of the local generation of platelet agonists such as thrombin and ADP.


Asunto(s)
Plaquetas/fisiología , Neutrófilos/fisiología , Adhesión Celular , Relación Dosis-Respuesta a Droga , Humanos , Inhibidores de la Lipooxigenasa/farmacología , Masoprocol/farmacología , Activación Neutrófila , Selectina-P/farmacología
9.
Am J Hematol ; 52(3): 135-43, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8756077

RESUMEN

Abnormal adhesion of sickle cells to vascular endothelium may be a factor in the initiation of painful vaso-occlusive crisis. The sickle cell population contains an unusually large number of less dense reticulocytes that are known to be more adhesive than mature red cells, but there is contradictory evidence regarding the adhesiveness of dense sickle cells. We used a flow-based assay of adhesion to cultured human umbilical vein endothelial cells to test the properties of density fractions of sickle cells, prepared either by density gradient or by centrifugation of packed cells. We also examined the effects of incubating sickle cells with or without cyclical deoxygenation on their adhesion. After fractionation on a Percoll-isopaque gradient, the less dense 10% (reticulocyte-rich) cells and the most dense 10% cells adhered in greater number than the remainder (by about twofold). However, after centrifugation of packed cells, the less dense 10% were again more adhesive than the "middle" cells, but the most dense were not. Exposing sickle cells to constituents of the gradient had no consistent effect on adhesion, while centrifugal packing induced a degree of hemolysis, and tended to reduce adhesiveness of the dense fraction previously obtained from a gradient. Incubation in air at 37 degrees C for 15 hr reduced the number of reticulocytes and the adhesiveness of less dense sickle cells compared to those held at 4 degrees C. On the other hand, incubation at 37 degrees C for 15 hr with cyclical deoxygenation caused formation of dense cells and increased adhesiveness compared to incubation without cyclical deoxygenation. We conclude that young, less dense sickle cells are unusually adhesive, but that this adhesiveness is reduced during maturation. However, repeated sickling in vivo causes formation of an abnormally dense subpopulation of cells which either redevelop an increased tendency to adhere to endothelial cells or preserve their initial adhesiveness. Both adhesive cell populations may be implicated in promoting vascular obstruction.


Asunto(s)
Anemia de Células Falciformes/sangre , Agua Corporal/metabolismo , Endotelio Vascular/fisiología , Eritrocitos/metabolismo , Eritrocitos/patología , Adulto , Adhesión Celular , Células Cultivadas , Senescencia Celular , Centrifugación , Deshidratación , Endotelio Vascular/citología , Recuento de Eritrocitos , Eritrocitos/fisiología , Humanos
10.
Br J Haematol ; 86(4): 820-3, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7918079

RESUMEN

To study the effect of anti-sickling drugs on cellular dehydration induced by entry of Ca, sickle cells were subjected to cyclical oxygenation-deoxygenation for 15 h in Ca-containing buffer. The consequential loss of cation (K) via the Ca-dependent K efflux (Gardos) channel caused cell dehydration and loss of deformability. Inhibition of a specific fraction of Ca entry by verapamil had no rheologically protective effect, whereas inhibition of the Gardos channel by clotrimazole or nitrendipine had a marked protective effect. When Gardos channel inhibition (by either clotrimazole or nitrendipine) was combined with stabilization of the oxy-conformation of sickle haemoglobin (by the substituted benzaldehyde 12C79), an additive protective rheological effect was achieved with 60-78% reduction in clogging rate of 5 microns diameter pores when compared with no drug. Therapeutic use of anti-sickling compounds in combination may achieve increased efficacy with lower toxicity.


Asunto(s)
Anemia de Células Falciformes/sangre , Antidrepanocíticos/farmacología , Eritrocitos/efectos de los fármacos , Hemorreología/efectos de los fármacos , Benzaldehídos/farmacología , Calcio/antagonistas & inhibidores , Células Cultivadas , Clotrimazol/farmacología , Sinergismo Farmacológico , Deformación Eritrocítica/efectos de los fármacos , Índices de Eritrocitos/efectos de los fármacos , Humanos , Nitrendipino/farmacología , Oxidación-Reducción , Potasio/sangre , Canales de Potasio/efectos de los fármacos , Verapamilo/farmacología
11.
J Clin Pathol ; 47(2): 166-9, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7510726

RESUMEN

AIMS: To identify suitable acute phase proteins as objective markers of tissue ischaemia during painful vaso-occlusive crises in sickle cell disease. METHODS: The prodromal and established phases of 14 vaso-occlusive crises were studied longitudinally in 10 patients with sickle cell anaemia. Automated solid phase enzyme immunoassays were used to measure the fast responding acute phase proteins C-reactive protein and serum amyloid A protein. Slower responding glycoproteins (fibrinogen, orosomucoid, sialic acid and concanavalin-A binding) were measured in parallel. RESULTS: C-reactive protein and serum amyloid A protein increased early in crisis, sometimes within the early (prodromal) phase. Crises that resolved within 24 hours in hospital showed a minor and transient rise compared with crises that required treatment for four days or more. In eight crises treated by patients at home the acute phase response ranged from minor to a level consistent with extensive tissue ischaemia. CONCLUSIONS: Sensitive enzyme immunoassays for C-reactive protein and serum amyloid A protein are of potential value for monitoring the onset of tissue ischaemia in sickle cell crisis and for confirming subsequent resolution.


Asunto(s)
Proteínas de Fase Aguda/metabolismo , Anemia de Células Falciformes/complicaciones , Enfermedades Vasculares Periféricas/diagnóstico , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Humanos , Isquemia/sangre , Isquemia/diagnóstico , Estudios Longitudinales , Enfermedades Vasculares Periféricas/sangre , Enfermedades Vasculares Periféricas/etiología , Proteína Amiloide A Sérica/metabolismo
12.
Br J Pharmacol ; 106(4): 972-7, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1393295

RESUMEN

1. Selected Ca-channel antagonists were tested at 20 microM as inhibitors of Ca(2+)-uptake in human sickle red cells. Nitrendipine, fendiline, and bepridil (and its stereoisomers), were found to be as effective as methoxyverapamil (D-600) in inhibiting a fraction (25%) of Ca(2+)-uptake. In contrast cetiedil and Org 30701 were ineffective. 2. The drugs were subsequently tested as inhibitors of Ca(2+)-induced K+ efflux (Gardos) from sickle cells. They all showed inhibitory activity, with the order of efficacy nitrendipine greater than fendiline greater than bepridil greater than cetiedil greater than Org 30701. 3. With a 15 h programme of deoxygenation/reoxygenation cycles in a gas exchanger, it was shown that the inhibitors protected against cellular dehydration and loss of filterability in the order nitrendipine greater than fendiline greater than bepridil greater than cetiedil greater than Org 30701. However, significant stomatocytosis occurred at high concentrations of cetiedil, and bepridil (including its stereoisomers and analogues) impairing cell deformability. 4. It is concluded that Ca-antagonists may partially block both Ca(2+)-uptake and Ca(2+)-induced K+ efflux. The latter pathway is significant in contributing to sickle cell dehydration and nitrendipine is the most effective inhibitor of this route.


Asunto(s)
Anemia de Células Falciformes/sangre , Bloqueadores de los Canales de Calcio/farmacología , Calcio/farmacología , Eritrocitos Anormales/efectos de los fármacos , Azepinas/farmacología , Bepridil/farmacología , Calcio/sangre , Fendilina/farmacología , Humanos , Técnicas In Vitro , Nitrendipino/farmacología , Oxígeno/metabolismo , Canales de Potasio/efectos de los fármacos
13.
Br J Haematol ; 81(3): 419-23, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1390217

RESUMEN

Reversibly sickled cells from patients with homozygous sickle-cell disease were prepared by Percoll-Isopaque density gradient separation and subjected to 15 h of cyclical deoxygenation-reoxygenation in the presence of Ca. After 15 h the sickle cells became dehydrated, losing volume secondary to K efflux via the Ca-activated (Gardos) channel, and showed impaired filterability through 5 microns diameter pores. The substituted benzaldehydes 12C79 and 589C80, which stabilize the oxy-conformation of sickle haemoglobin, showed an additional protective effect at pharmacological concentration by maintaining the K concentration, mean cell volume, and deformability of sickle cells. Drugs that increase the oxygen affinity of sickle haemoglobin may be more effective than specific inhibitors of Ca entry or K efflux in preserving the cation homeostasis and deformability of sickle cells during sickling in vivo.


Asunto(s)
Anemia de Células Falciformes/sangre , Antidrepanocíticos/farmacología , Benzaldehídos/farmacología , Benzoatos/farmacología , Calcio/farmacología , Deshidratación/sangre , Eritrocitos Anormales/patología , Oxihemoglobinas/metabolismo , Anemia de Células Falciformes/metabolismo , Anemia de Células Falciformes/patología , Deshidratación/metabolismo , Deshidratación/prevención & control , Eritrocitos Anormales/efectos de los fármacos , Eritrocitos Anormales/metabolismo , Humanos , Oxihemoglobinas/efectos de los fármacos , Potasio/análisis , Potasio/metabolismo
14.
Radiol Clin North Am ; 30(2): 495-501, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1535869

RESUMEN

This article reviews the current legal environment in which radiologists practice medicine and some of the key problems radiologists may experience. Particular attention is given to the need for accurate communication, complete charting, and carefully performed procedures. Information is also provided about the requirements for informed consent. Recommendations are made for dealing with patient grievances and with patients' attorneys after a lawsuit has arisen.


Asunto(s)
Servicio de Urgencia en Hospital/legislación & jurisprudencia , Mala Praxis/legislación & jurisprudencia , Radiología/legislación & jurisprudencia , Comunicación , Errores Diagnósticos , Documentación , Humanos , Enfermedad Iatrogénica , Consentimiento Informado , Relaciones Médico-Paciente , Estados Unidos
15.
J Mal Vasc ; 16(1): 46-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2010707

RESUMEN

The water content of the human erythrocyte is a major determinant of its cytoplasmic viscosity and thus deformability. Loss of cell water may be either primary or secondary to loss of erythrocyte cations (K+). Several existing drugs (cetiedil citrate, pentoxifylline and piracetam) have recently been shown to inhibit K+ loss from erythrocytes and thus have the potential to prevent erythrocyte dehydration. Further studies of cation flux pathways in the erythrocyte membrane are of importance for the development of new drugs that maintain cell hydration.


Asunto(s)
Azepinas/uso terapéutico , Eritrocitos , Pentoxifilina/uso terapéutico , Piracetam/uso terapéutico , Desequilibrio Hidroelectrolítico/tratamiento farmacológico , Deformación Eritrocítica , Humanos , Reología
16.
J Clin Pathol ; 40(10): 1182-6, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3119675

RESUMEN

Erythrocytes from 14 patients with homozygous sickle cell anaemia were treated with the calcium ionophore A23187 to induce loss of cellular potassium and water. The dehydrated cells showed a decrease in filterability (loss of deformability) through pores of 5 micron diameter. Oxpentifylline and cetiedil citrate, which preserve erythrocyte cation and water content, had a significant (p less than 0.01) protective effect against loss of deformability at a concentration of 1 mumol/l. Oxpentifylline showed no adverse effect on the rheology, morphology, or haemolysis of sickle cells at concentrations up to 500 mumol/l. Drugs that act on the erythrocyte membrane to maintain cell hydration are of potential rheological benefit in sickle cell anaemia.


Asunto(s)
Anemia de Células Falciformes/sangre , Antidrepanocíticos/farmacología , Azepinas/farmacología , Eritrocitos Anormales/efectos de los fármacos , Pentoxifilina/farmacología , Teobromina/análogos & derivados , Calcimicina/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Deformación Eritrocítica/efectos de los fármacos , Humanos
17.
Eur J Clin Invest ; 17(4): 317-24, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3117569

RESUMEN

Problems arise in distinguishing skeletal from cardiac muscle trauma on the basis of serum enzyme tests following severe muscle exercise. The contributions of cardiac and skeletal sources have been assessed in eleven marathon runners by measuring pre- and post-race serum levels of cardiac-specific myofibrillar troponin-I together with total creatine kinase, creatine kinase-MB isoenzyme, myoglobin, myofibrillar tropomyosin and C-reactive protein. Total creatine kinase, creatine kinase-MB isoenzyme, tropomyosin and myoglobin were significantly elevated above pre-race levels in all runners between 1 h and 128 h post-race. Neither mean cardiac troponin-I nor C-reactive protein was elevated post-race. Nine out of sixty-three samples fulfilled conventional positive criteria for cardiac muscle damage on the basis of combined creatine kinase and creatine kinase-MB isoenzyme levels. Six runners had one or more positive samples. No samples had levels above twice the upper normal limit for either cardiac troponin-I or C-reactive protein. Correlation analysis of levels in each sample indicated skeletal and not cardiac muscle as the source of raised serum protein.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Lesiones Cardíacas/fisiopatología , Proteínas Musculares/metabolismo , Músculos/lesiones , Carrera , Proteína C-Reactiva/metabolismo , Creatina Quinasa/metabolismo , Humanos , Isoenzimas , Masculino , Proteínas Musculares/sangre , Músculos/metabolismo , Mioglobina/metabolismo , Tropomiosina/metabolismo , Troponina/metabolismo
18.
J Clin Pathol ; 39(7): 722-7, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3090107

RESUMEN

Erythrocyte deformability was studied in a total of 83 poorly controlled diabetics (mean blood glucose 12.2 mmol/l) who were divided into three groups, each with matched healthy controls. There was no appreciable difference between diabetics and matched controls regarding the filtration of erythrocytes through 3 micron diameter straight channel pores (25 diabetics) or tortuous channel pores (28 diabetics), or for the measurement of erythrocyte elongation over a range of osmolalities in the Ektacytometer (30 diabetics). When erythrocytes from 17 additional diabetics and 17 healthy controls were incubated for two hours at 37 degrees C in hyperglycaemic (50 mmol glucose/l) buffer, however, there was a considerable reduction in erythrocyte filterability for both diabetics and controls in parallel with an increase in erythrocyte sorbitol concentration. This loss of filterability was prevented by the addition of an aldose reductase inhibitor (Sorbinil). High glucose concentrations (congruent to 50 mmol/l) impair the filterability of erythrocytes through 3 micron pores, and the intracellular accumulation of sorbitol in poorly controlled outpatients is therefore unlikely to have a major adverse effect on erythrocyte rheology in diabetes mellitus.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Deformación Eritrocítica , Imidazolidinas , Sorbitol/sangre , Adulto , Anciano , Aldehído Reductasa/antagonistas & inhibidores , Deformación Eritrocítica/efectos de los fármacos , Femenino , Glucosa/farmacología , Humanos , Imidazoles/farmacología , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Concentración Osmolar
19.
J Clin Pathol ; 38(2): 135-9, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2857183

RESUMEN

A rheological study of 32 patients with peripheral occlusive arterial disease (POAD), compared with 32 matched healthy controls, has shown no loss of erythrocyte deformability as measured by filtration methods (using initial flow rate and positive pressure instruments, polycarbonate and silver membranes, and 3 microns and 5 microns diameter pores) or by viscometry (using laser visco-diffractometric and high shear rate viscosity methods). Erythrocyte ATP concentration in POAD was also normal. Patients with POAD showed a small (4 fl) increase in mean erythrocyte volume, associated with a raised serum gamma-glutamyl transpeptidase concentration, which correlated with erythrocyte filtration and viscometric measurements. Previous reports of impaired blood filterability in POAD probably reflect the effects of accompanying leucocytosis, plasma hyperfibrinogenaemia, or an increase in erythrocyte size, but not an intrinsic loss of erythrocyte deformability.


Asunto(s)
Arteriopatías Oclusivas/sangre , Deformación Eritrocítica , Adenosina Trifosfato/sangre , Anciano , Viscosidad Sanguínea , Índices de Eritrocitos , Femenino , Humanos , Masculino , Persona de Mediana Edad , gamma-Glutamiltransferasa/sangre
20.
J Clin Pathol ; 37(7): 821-5, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6430971

RESUMEN

Three rapid assay techniques (latex agglutination, laser nephelometry, and EMIT enzyme immunoassay) have been evaluated for serial monitoring of the serum C reactive protein (CRP) concentration in immunosuppressed patients with fever. Radial immunodiffusion assay was used as a reference method. Latex agglutination reliably distinguished between normal and raised serum CRP concentrations. Enzyme immunoassay also provided a result within minutes, showed particularly close correlation (r = 0.967) with the reference method, and was free from interference by lipaemic or icteric sera. In 27% of 55 episodes of fever studied serially in immunosuppressed patients, the enzyme immunoassay provided clinically useful information by indicating incomplete resolution of infection despite resolution of fever.


Asunto(s)
Infecciones Bacterianas/sangre , Proteína C-Reactiva/análisis , Tolerancia Inmunológica , Fiebre/sangre , Humanos , Inmunodifusión , Técnicas para Inmunoenzimas , Rayos Láser , Pruebas de Fijación de Látex , Nefelometría y Turbidimetría
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