[Face-to-face education to optimize knowledge in patients initiating oral anticoagulant treatment (OAT)]. / Intervención educativa individualizada (IEI) cara a cara para optimizar el conocimiento de pacientes que inician tratamiento anticoagulante oral (TAO).

BACKGROUND: Insufficient knowledge of patients about oral anticoagulants that they have been prescribed is recognized as a risk factor for adverse effects. Education of patients under oral anticoagulation may improve quality and control of anticoagulant treatment; limitations of educational interventions include lack of assessment of patients' knowledge. Our goal was to determine the effect of an individualized educational intervention on knowledge of patients who recently started treatment with oral anticoagulants, to assess patients' knowledge, and to analyze factors associated with knowledge acquisition. METHODS: In 49 consecutive patients attending a thrombosis clinic who initiated or re-initiated oral anticoagulant treatment, knowledge about the treatment was assessed by means of a validated questionnaire, before an individualized, face-to-face educational intervention, and at least four weeks after. Educational intervention started after the questionnaire had been answered by patients for the first time. RESULTS: Knowledge level increased by about 50%; the improvement was higher in patients with more years in school. DISCUSSION: Timely acquisition of knowledge about oral anticoagulant drugs is optimized with interventions provided earlier during the patients' treatment. Assessment of knowledge should be performed and instruction should be adapted to patient characteristics such as level of education and availability to receive education.

Pulsatile diastolic increase and systolic decrease in arterial blood pressure: their mechanism of production and physiological role.

The diastolic pulsatile increase in arterial blood pressure is shown to occur earlier in the aorta than in other arteries. It is thus not a reflection of the systolic pressure wave, as has been generally assumed, but an independent pressure wave produced by the sequential contraction of the arterial tree. Conversely, a systolic pulsatile decrease in the rate of blood pressure rise is also produced by an active relaxation of the arterial tree. Simultaneously with the pulsatile changes in arterial blood pressure, there are corresponding changes in arterial blood flow. All these cyclic changes are reflex responses to decreasing diastolic and increasing systolic baroreceptor firing rates, respectively. The two reflexes contribute, together with the known compliance of the large arteries and the great arteriolar blood flow resistance, to the steadiness of capillary blood flow throughout the systolic and the much longer-lasting diastolic phases of the cardiac cycle.

Differential effects of esculetin and daphnetin on in vitro cell proliferation and in vivo estrogenicity.

Esculetin (6,7-dihydroxycoumarin) and daphnetin (7,8-dihydroxycoumarin) are secondary metabolites of plants used in folk medicine. These compounds have showed great antiproliferative activity in several tumor cell lines and have been proposed as potential anticancer agents. However, the estrogenic potential of these two compounds has to date not been reported. The present study compared esculetin and daphnetin on the inhibition of cell proliferation and cell cycle progression of the MCF-7 estrogen-responsive human carcinoma cell line. In vivo and in vitro estrogenic activity for both compounds was also evaluated. Esculetin inhibited cell proliferation after 72 h exposure (IC50=193 ± 6.6 µM), while daphnetin evidenced inhibiting effects starting at 24-h exposure (72 h, IC50=73 ± 4.1 µM). Both effects showed changes in cyclin D1 gene expression. In non-estrogenic conditions (E-screening assay), esculetin produced biphasic response on proliferation of the MCF-7 cells; at 10(-8)-10(-6)M, concentrations induced proliferative effects as EC50=4.07 × 10(-9)M (E(2)=2.91 × 10(-12)M); at higher concentrations (10(-5)-10(-4)M), cell proliferation was inhibited. Relative proliferative effect at E(2) was 52% (E(2)=100), relative proliferative potency was 0.072 (E(2)=100). Additionally, esculetin tested in vivo showed estrogenic effects at 50-100mg/kg doses; relative uterotrophic effect at E(2) was 37%, with relative uterotrophic potency registered at 0.003. In contrast, daphnetin did not induce estrogenic effects in vitro or with in vivo models. The low estrogenic activity of esculetin could prove useful in postmenopausal therapy but not as a safe antitumor agent in estrogen-dependent tumors. Daphnetin-based antiproliferative selectivity with MCF-7 cells showed that daphnetin is a promising antitumoral agent also acting on estrogen dependent tumors.

Reflections on the mode of functioning of endocrine systems.

The concept of hormones as chemical messengers that transmit information from one organ to other organs by way of circulating blood has implications that have not been made explicit. In this paper the concept is analyzed and is shown to be inconsistent with many observations. The previously proposed concepts of hormone multifunctionalities, hormonal multisignal messages, and the conversion of hormones into other hormones are shown to clarify conflicting observations as well as the congruous mode of functioning of endocrine systems with multifunctional hormones. A strategy is proposed for identifying the compositions and functions of the diverse multisignal messages conveyed by any hormone. The information so obtained could be useful for the development of more selective hormonal therapies.

Lung carcinomas decrease the number of monocytes/macrophages (CD14+ cells) that produce TNF-alpha.

The role that inflammation plays in cancer is puzzling. In peripheral blood, TNF-alpha-producing monocytes (CD14+ cells) were compared among patients with lung cancer, patients with tuberculosis and healthy donors; also, in pleural effusion TNF-alpha-producing CD14+ cells were compared between tuberculous patients and lung cancer patients. To analyze the level of the cellular alteration in TNF-alpha production, an experimental model was set up. TNF-alpha-producing CD14+ cells in peripheral blood from lung cancer patients were significantly lower than those from healthy donors. In pleural effusion, TNF-alpha-producing CD14+ cells were significantly lower in lung cancer patients than in tuberculous patients. Based on the results obtained from an experimental model, we suggest that this phenomenon was attributed to a reduced expression of TNF-alpha transcript. These findings provide evidence that lung carcinomas reduce TNF-alpha production by macrophages, possibly by inducing in these cells an M2 phenotype, which favor tumor progression.

Effector, memory and naïve CD8+ T cells in peripheral blood and pleural effusion from lung adenocarcinoma patients.

The proportions of naïve, memory and effector CD8+ T cells in peripheral blood and pleural effusion from lung adenocarcinoma patients were studied. CD8+ T subsets were identified by using a combination of the following antibodies: anti-CD45RA, anti-CD45RO, anti-CD27 and anti-CD28, as well as antibodies to other markers. Fas-positive cells were determined in each CD8+ T subset. Also, the intracellular cytokine patterns of CD4+ and CD8+ lymphocytes from pleural effusion were analysed. In naïve, memory and effector CD8+ T subsets no significant differences were observed in peripheral blood between healthy donors and cancer patients. In contrast, a high proportion of cells with memory phenotype (CD45RA-CD45RO+CD27+CD28+) and a low proportion of cells with effector phenotype (CD45RA+CD45RO-CD27-CD28-) were found in pleural effusion with respect to peripheral blood (P<0.001). The altered proportions of CD8+ T subsets in pleural effusion were not mediated by type 2 cytokines produced by CD4+ or CD8+ lymphocytes. In the effector CD8+ T subset, from peripheral blood as well as from pleural effusion, a low percentage of perforin-expressing cells was observed compared to granzyme A-expressing cells. Additionally, a high percentage of naïve CD8+ T cells expressing Fas was found. Our data suggest that: (i) terminal-differentiation process of CD8+ T cells is blocked, and (ii) early Fas-expression in CD8+ T cells, which was reflected even in peripheral blood, may lead to apoptosis of naïve cells when they reach the effector stage. All these processes may contribute to the inadequate antitumour immune response found in lung carcinoma patients.

Effects of single administration of diethylstilbestrol on murine langerhans cells.

Diethylstilbestrol (DES) is a synthetic compound with potent estrogenic actions useful in the treatment of prostate carcinoma despite the fact that it can also induce some forms of neoplasia. Both effects are thought to be related to its estrogenic actions and very little attention has been focused on the possible effect of DES on the immune response. Skin is the largest organ of the body and constitutes the first line of defense against xenobiotics. The Skin Immune System (SIS) has become the center of attention of research for the development of new therapeutic approaches for neoplasic diseases. Langerhans cells (LC), as an element of SIS, are "professional" antigen presenting cells resident in the skin that participate in the immune response associated with tolerance and acquired immunity to antigens. Hence in this work we studied the effect of DES on LC of murine skin as a model to analyze the possible effect of DES on the immune response. Male CD-1 mice (20 to 35 g body weight) were treated topically (TO) or subcutaneously (SC) with DES (10 and 100 mg/kg, dissolved in ethanol) and sacrificed at 12, 84 and 228 hr. LC were quantified in the ear skin of mice using both an enzymatic histochemical technique to demonstrate ATP-ase activity; and an indirect immunohistochemical assay for detecting class II molecules of the major histocompatibility complex (MHC-II). DES induced a significant time- and dose- dependent reduction in the number of LC (P < 0.05). Data presented here suggest that estrogens may exert a modulatory action on LC.

Hormone multifunctionalities: a theory of endocrine signaling, command and control.

A theory is presented outlining how organisms can function and benefit from multifunctionality of hormones in order to enhance greatly the information-carrying potential of endocrine signaling. Hormones are produced continuously as micropulses, and intermittently as larger pulses. It is generally believed that micropulses generate fluctuating basal hormone concentrations, which may consistently elicit particular responses among diverse variables. Evidence is discussed suggesting that in contrast to the hormone micropulses, the larger endogenous hormone pulses may elicit responses which may differ from one pulse to another and may therefore serve different physiological functions. In this paper we postulate that an endogenous hormone pulse is a specific form of a multisignal message that serves a certain physiological function. Different pulses of a hormone may be signals of diverse multisignal messages that serve different functions. A multisignal message may elicit congruous responses by selectively enhancing some actions and suppressing other actions of the component signals. Various roles of signals of multisignal messages are discussed, as well as processes that may be involved in the diversity and selectivity of actions of different pulses of a hormone. Hormones also are converted into other hormones; we analyze how precursor and derived hormones may function independently of each other, and how precursor hormones may give rise to permissive effects. Mechanisms involved in therapeutic and adverse effects of hormone administrations are analyzed, and a strategy is suggested for developing more selective hormonal therapies.

Apoptosis and cell cycle disturbances induced by coumarin and 7-hydroxycoumarin on human lung carcinoma cell lines.

Coumarin and 7-hydroxycoumarin have anti-tumour actions in vitro and in vivo. There are no previous reports on the cytostatic and apoptotic actions of coumarin and 7-hydroxycoumarin in non-small cell lung carcinoma (NSCLC) cell lines. Here we report on: (1) the inhibition of cell proliferation, (2) the phase in which cell cycle arrest occurs, and (3) the induction of apoptosis. Inhibition of cell proliferation was determined by 3H-thymidine incorporation. The effects on cell cycle phases were determined at 100 microg/ml of coumarin or 7-hydroxycoumarin using propidium iodide and flow cytometry. Higher concentrations were used to study apoptosis, detected by: (1) morphological cell changes, (2) subG1 peak detection and (3) Annexin-V assay. Peripheral blood mononuclear cells (PBMC) stimulated with phytohemagglutinin were used as controls. The actions of these compounds depended on drug concentrations and on histological cell type. Coumarin and 7-hydroxycoumarin inhibited cell growth by inducing cell cycle arrest in the G1 phase in all the lung carcinoma cell lines. Apoptosis required large concentrations of the coumarin compounds and was observed in adenocarcinomas. Apoptosis was not associated with intra-nucleosomal DNA fragmentation. Apoptosis was not observed in squamous lung carcinoma cell lines, but an increase in G1 cell cycle arrest was detected. In PBMC, only large concentrations of the coumarin compounds elicited a cystostatic action. Coumarins in combination with other anti-neoplastic drugs might increase the effectiveness of NSCLC treatments.

Lack of correlation between growth inhibition by TGF-beta and the percentage of cells expressing type II TGF-beta receptor in human non-small cell lung carcinoma cell lines.

To determine the mechanisms involved in the evasion from TGF-beta growth regulation in the small cell lung carcinoma (SCLC) cell lines and the non-small cell lung carcinoma (NSCLC) cell lines, we studied: (a) production of TGF-beta1 and TGF-beta2; (b) percentage of cells expressing TGF-beta RII; (c) responsiveness of the tumour cell lines to exogenous TGF-beta1 or TGF-beta2; and (d) presence of mRNA transcripts of the three TGF-beta isoforms and of the TGF-beta RII. Our results indicate that the SCLC cell lines do not synthesize the isoforms TGF-beta1 and TGF-beta2 nor the TGF-beta RII, thus avoiding inhibitory autocrine and paracrine TGF-beta actions. However, NSCLC cell lines express not only TGF-beta1, TGF-beta2 and TGF-beta RII mRNA transcripts, but also synthesize both isoforms and the TGF-beta RII. Although approximately 50% of the cells from the studied cell lines expressed the TGF-beta RII, different cell lines varied greatly in the sensitivity to the inhibitory action of TGF-beta. This could result from alterations in: (i) the structure of TGF-beta RII; (ii) the phosphorylation motif of TGF-beta RI; (iii) the molecules involved in the intracellular signalling pathway of TGF-beta; and (iv) cell cycle regulation.

Efecto en el ciclo celular de líneas de adenocarcinoma pulmonar por cumarina y 7-hidroxicumarina / Effects of cumarine and 7-hydroxicumarine on the cell cycle of pulmonary adenocarcinoma cell lines

Introducción: Las cumarinas son compuestos ampliamente distribuidos en la naturaleza. En el humano el principal metabolito de la cumarina es la 7-hidroxicumarina. Estos compuestos presentan actividad antitumoral in vitro e in vivo. Previamente reportamos que la cumarina y la 7-hidroxicumarina ejercen actividad citostática en líneas de adenocarcinoma; sin embargo, se desconocen los aspectos relacionados a la fase del ciclo celular en la que estos compuestos pueden actuar.Objetivo: Determinar el efecto de la cumarina y la 7-hidroxicumarina en la transición del ciclo celular en líneas de adenocarcinoma pulmonar.Material y métodos: Tres líneas de adenocarcinoma pulmonar (SK-LU-1, 1.3.15 y 3A5A) y células mononucleares de individuos sanos estimuladas con fitohemaglutinina, se incubaron por 24h y 40h respectivamente, con 100 µg/mL de cumarina o 7-hidroxicumarina. Las perturbaciones en el ciclo celular se evaluaron por medio de la determinación de contenido de DNA por citometría de flujo.Resultados: Posterior al tratamiento, las líneas celulares presentaron acumulación significativa de células en la fase G0/G1, disminuyendo proporcionalmente la población de células en la fase S. En cambio, las células mononucleares no presentaron cambios significativos después del tratamiento.Conclusiones: Estos resultados demuestran que los compuestos cumarínicos causan un arresto de las células tumorales en la fase G0/G1. El conocimiento de las perturbaciones en el ciclo celular, inducidas por estos productos, puede facilitar la elaboración de esquemas de tratamiento mediante combinaciones con otros fármacos que arresten en distinta(s) fase(s) del ciclo. Además, esta metodología permite evaluar la susceptibilidad de las células tumorales a los agentes quimioterapéuticos.

Ciclo celular y sus anormalidades en el cáncer de pulmón / Cell cycle and its abnormalities in lung cancer

En esta revisión se describen los eventos celulares que ocurren normalmente en cada fase del ciclo celular. Se explica el papel de las proteínas que promueven la progresión del ciclo celular y las que lo detienen. En el cáncer de pulmón, los tipos de genes que presentan mutaciones con mayor frecuencia son: 1) los oncogenes c-ras y c-myc, 2) los genes supresores de tumores, RB y p53, y 3) el gen de la proteína inhibidora de Cdk p16. Las proteínas codificadas por estos genes mutados sufren cambios funcionales, lo que origina la pérdida del control del ciclo celular. La acumulación gradual de errores en genes conducen a tumores malignos

Integrinas y moléculas asociadas a integrinas: blancos para el desarrollo de terapias antimetastásicas / Integrins and integrin-associated molecules: targets for the development of antimetastasic therapies

Las integrinas son receptores que median la adhesión celular y regulan la formación de complejos de señalización. Se requieren modificaciones en la expresión de integrinas durante las siguientes etapas de la generación de metástasis: a) angiogénesis intratumoral; b) desprendimiento del tumor primario; c) interacción de células tumorales con plaquetas; d) adhesión al endotelio vascular y e) proliferación. Existe, también, correlación entre la capacidad invasiva y la expresión alterada de algunas proteínas que se agregan en los sitios de adhesión focal, como la cinasa de adhesión focal (FAK), CD82, CD9 o CD63. Tanto el bloqueo de integrinas (utilizando anticuerpos o péptidos que contienen la secuencia RGD) como modificaciones inducidas en la expresión de moléculas asociadas a integrinas pueden inhibir la formación de metástasis. El descubrimiento y caracterización de moléculas que regulen la capacidad adherente de la células tumorales conducirá al desarrollo de tarapias antimetastásicas. En la búsqueda de inhibidores de la diseminación tumoral, las integrinas y algunas moléculas asociadas a integrinas son importantes blancos farmacológicos