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BACKGROUND: Motivational interviewing led by nurses has been demonstrated to be effective in reducing alcohol consumption among university students. However, most of these professionals feel that they lack the competence necessary for motivational interviewing due to a lack of formal training in the nursing curriculum. OBJECTIVES: To design, implement and evaluate a motivational interviewing training course for alcohol misuse in an undergraduate nursing curriculum and to explore students' experiences with this course. DESIGN: A mixed-methods study involving a descriptive comparative quantitative design and qualitative focus group interviews with nursing students. SETTINGS: An elective nursing course in a Spanish university. PARTICIPANTS: A total of 21 fourth-year nursing students. METHODS: The course was developed as a twelve-week, two-hour course. It comprised three modules covering the concepts, tools and skills associated with motivational interviewing for alcohol misuse. Quantitative and qualitative data were collected after the completion of the course to evaluate the training received by students; these data were categorized using Kirkpatrick's model. The quantitative results included students' satisfaction, knowledge, skills and attitudes, which were measured using an ad hoc questionnaire, a multiple-choice exam, and two rater-based assessments (the Peer Proficiency Assessment instrument and an evidence-based checklist). Qualitative focus groups were used to explore students' experiences of the entire programme. RESULTS: Students' satisfaction with the course was rated 9 out of 10, highlighting the usefulness and adequacy of the course content. The quantitative and qualitative results both indicated that all students acquired the knowledge necessary to perform motivational interviewing and significantly improved their motivational interviewing microskills. Only half of the students reached the level of proficiency in two of the three ratios calculated. The three main themes identified pertained to the learning atmosphere, module methodologies, and students' self-perceptions of competence. Finally, the students reported having transferred their learning to clinical practice. CONCLUSION: A course on motivational interviewing for alcohol misuse positively influences nursing students both personally and in terms of their future professional work by improving their knowledge, skills, attitudes and self-perceived competence.
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Alcoholismo , Bachillerato en Enfermería , Entrevista Motivacional , Estudiantes de Enfermería , Humanos , Entrevista Motivacional/métodos , Bachillerato en Enfermería/métodos , Alcoholismo/prevención & control , Aprendizaje , CurriculumRESUMEN
AIM: To explore nurses' knowledge, skills and personal attributes for competent health education practice and their association with potential influencing factors. BACKGROUND: Clinical nurses are expected to perform effective health education interventions, but they do not feel competent. The self-assessment of the health education competence and its conditional factors is paramount for professional development. DESIGN: A cross-sectional study. METHODS: A total of 458 clinical nurses from two health specialized centers in Spain participated in this study. Data were collected using the Nurse Health Education Competence Instrument and a second self-report questionnaire from January to February 2019. Descriptive statistics, t-test, analysis of variance, Pearson's and Spearman's correlation and multiple linear regression were used to analyse the data. The STROBE guideline was used RESULTS: The mean scores of the knowledge (70.10 ± 15.11), skills (92.14 ± 15.18) and personal attributes scales (32.32 ± 5.89) were found to be low to moderate. The main influencing factors for the health education implementation were lack of education and training (71.4%), lack of time (67.5%) and high workload (67.3%). Nurses with higher educational level and perceived self-efficacy for competently providing health education, more extensive professional experience and previous training in health education rated higher in knowledge, skills and personal attributes. Age and years of experience were negatively correlated with knowledge scores, but positively with the rest of domains of the competence and self-efficacy. The regression models for the overall health education competence's domains were significant (p < 0.001) with R2 values ranging from 28.0% to 49.3%. Self-efficacy, previous health education training and working in intensive care units were found to be significant in all cognitive, psychomotor and attitudinal scales. CONCLUSION: Clinical nurses reported on some skills and personal attributes for health education practice, but they seem to lack health education knowledge necessary for a competent practice. This study suggested that effective education and training and supportive organizational cultures are key to enhance nurses' health education competence. Identifying nurses' educational needs on the main domains of the competence and its intrinsic/extrinsic influential factors may assist in both planning and organizing tailored training strategies and in promoting appropriate environments to support a high-quality health education practice TWEETABLE ABSTRACT: Nurses' knowledge, skills and attitudes about health education competence are low to moderate. Training and organizational support are key.
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Competencia Clínica , Enfermeras y Enfermeros , Estudios Transversales , Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Humanos , Encuestas y CuestionariosAsunto(s)
Fármacos Anti-VIH/efectos adversos , Síndrome de Fanconi/inducido químicamente , Infecciones por VIH/complicaciones , Rabdomiólisis/inducido químicamente , Tenofovir/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Sulfato de Atazanavir/uso terapéutico , Quimioterapia Combinada , Fluidoterapia , Tasa de Filtración Glomerular/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Nevirapina/uso terapéutico , Rabdomiólisis/terapia , Tenofovir/uso terapéuticoRESUMEN
Introducción: El Trastorno Dismórfico Corporal es un trastorno propio de la adolescencia, poco conocido y poco tenido en cuenta en la clínica diaria con niños y adolescentes, lo que demora el diagnóstico y empeora el pronóstico. Métodos: Se realizó una revisión sistemática práctica para el clínico infanto-juvenil, con una búsqueda electrónica en las principales bases de datos junto a una búsqueda manual en revistas y tratados especializados. Resultados: El trastorno es muy común, con prevalencias del 1,7 al 2,5%. Dos terceras partes de los casos se inician en la adolescencia y una edad de inicio más temprana se asocia a mayor probabilidad de comorbilidad a lo largo de la evolución y a un mayor riesgo suicida. Se trata de un trastorno del espectro obsesivo-compulsivo que implica preocupaciones persistentes por uno o más defectos físicos percibidos y que no son observables por otras personas, así como comportamientos compulsivos en respuesta a dichas preocupaciones. La vergüenza y el miedo al rechazo promueven que el adolescente no explique sus síntomas y es muy habitual la demora de años en el diagnóstico, que si llega a establecerse, lo hace por lo general en la edad adulta. El curso es crónico y en caso de no diagnosticarse, el pronóstico será pobre con frecuente aislamiento social y deterioro funcional. Un diagnóstico correcto y a tiempo mejorará mucho la evolución, tratándose de un trastorno que responde bien a los tratamientos tanto farmacológicos como psicológicos. Conclusión: Conocer el trastorno dismórfico corporal es muy importante para diagnosticarlo a tiempo en el adolescente, lo cual mejorará el pronóstico de forma clara
Introduction: Body Dysmorphic Disorder is a disorder of adolescence, not enough known and not always taken into account by child and adolescent clinicians, which delays diagnosis and worsens its prognosis. Methods: We aimed to carry out a practical systematic review for clinicians working with adolescents, by means of an electronic search using the main databases, along with a manual search in journals and specialized textbooks. Results: The disorder is very common, with prevalences of 1.7 to 2.5%. Two thirds of cases begin in adolescence and an earlier age of onset is more likely to be associated with comorbidity throughout the course of the disease and with an increased suicide risk. It is a disorder of the obsessive-compulsive spectrum that involves persistent concerns about one or more perceived physical defects that are not observable by others, as well as compulsive behaviors in response to those concerns. The shame and the fear of rejection prevent adolescents from explaining their symptoms and a delay of several years to diagnosis is very usual, with most of the diagnoses established in adult age, if they are ever reached. The course is chronic and if not diagnosed, the prognosis will be very poor, with frequent social isolation and functional deterioration. A correct diagnosis at an appropriate time will greatly improve clinical course as it is a disorder that responds well to both pharmacological and psychological treatments. Conclusion: Adequate knowledge of Body Dysmorphic Disorder in the adolescent is very important to diagnose it in time, which will improve prognosis very considerably
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Humanos , Adolescente , Trastorno Dismórfico Corporal/epidemiología , Trastorno Dismórfico Corporal/psicología , Conducta del Adolescente/psicología , Terapia Cognitivo-Conductual/métodos , Psicoterapia , Trastorno Dismórfico Corporal/etiología , Antipsicóticos/administración & dosificación , PsicofarmacologíaRESUMEN
La educación para la salud (EpS) en el paciente trasplantado y su familia es fundamental dada la importancia de promover un adecuado autocuidado en esta nueva etapa de la vida. La unidad de cuidados intensivos ofrece múltiples oportunidades a la enfermera para la promoción activa de la salud ya que en esta se puede iniciar el proceso educativo donde la interacción enfermera-paciente-familia es constante. La EpS eficaz del paciente trasplantado engloba tres dimensiones: los conocimientos -información relacionada con el autocuidado para llevar a cabo un estilo de vida saludable y para reducir la ansiedad del paciente y familia; las habilidades relacionadas con el poder y saber hacer, donde adquiere importancia la familia; y por último, las actitudes-ambivalentes, vivenciadas por el paciente trasplantado. El objetivo del trabajo es conocer el nivel de desarrollo de la EpS en una Unidad de Cuidados Intensivos para los pacientes críticos trasplantados y sus familias. Para ello, se desarrolla una revisión bibliográfica no sistemática en Pubmed y CINHAL. Como conclusiones, se destaca que el desempeño de la competencia enfermera de EpS en una Unidad de Cuidados Intensivos es importante para promover estilos de vida adecuados a las necesidades cognitivas, afectivas y psicomotoras del paciente trasplantado. Su puesta en práctica conlleva efectos positivos en los resultados clínicos del paciente, en la disminución de la morbimortalidad, costes y recursos sanitarios
Health Education (HE) is extremely important in transplant patients and their families in order to promote suitable self-care in this new stage of life. Intensive Care Units offer various opportunities by nurses in order to improve their Health Education. This process could start in this unit where the interaction between nurse and family is constant. The HE of transplant patient includes three dimensions: Knowledge: information about self-care in order to have a healthy way of life, and getting some information on how to reduce anxiety in patients and their families; Skills: as regards the abilities to properly apply the Health Education, where the families are really important; and finally Attitudes: ambivalent attitudes that are experienced by transplant patients. The objective is to describe the level of development of HE for critical transplant patients and their families from Intensive Care Units. A non-systematic literature review was performed in Pubmed and CINHAL data bases. In conclusion, it is emphasised that the skill of the HE nurse in an Intensive Care Units is important to promote lifestyles appropriate to the cognitive, affective, and psychomotor needs of transplant patients. Its implementation entails positive effects on clinical outcomes of the patient, decreased morbidity and mortality, costs, and health resources
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Humanos , Trasplante de Órganos/enfermería , Autocuidado/métodos , Cuidados Críticos/métodos , Cuidados Críticos/métodos , Educación en Salud/métodos , Educación del Paciente como Asunto/métodos , Relaciones Profesional-FamiliaRESUMEN
Health Education (HE) is extremely important in transplant patients and their families in order to promote suitable self-care in this new stage of life. Intensive Care Units offer various opportunities by nurses in order to improve their Health Education. This process could start in this unit where the interaction between nurse and family is constant. The HE of transplant patient includes three dimensions: Knowledge: information about self-care in order to have a healthy way of life, and getting some information on how to reduce anxiety in patients and their families; Skills: as regards the abilities to properly apply the Health Education, where the families are really important; and finally Attitudes: ambivalent attitudes that are experienced by transplant patients. The objective is to describe the level of development of HE for critical transplant patients and their families from Intensive Care Units. A non-systematic literature review was performed in Pubmed and CINHAL data bases. In conclusion, it is emphasised that the skill of the HE nurse in an Intensive Care Units is important to promote lifestyles appropriate to the cognitive, affective, and psychomotor needs of transplant patients. Its implementation entails positive effects on clinical outcomes of the patient, decreased morbidity and mortality, costs, and health resources.
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Educación en Salud , Unidades de Cuidados Intensivos , Salud de la Familia , Humanos , AutocuidadoRESUMEN
The authors report a compact and highly selective tunable filter using a Fabry-Perot resonator combining a bottom micromachined 3-pair-InP/air-gap Bragg reflector with a top photonic crystal slab mirror. It is based on the coupling between radiated vertical cavity modes and waveguided modes of the photonic crystal. The full-width at half maximum (FWHM) of the resonance, as measured by microreflectivity experiments, is close to 1.5nm (around 1.55 microm). The presence of the photonic crystal slab mirror results in a very compact resonator, with a limited number of layers. The demonstrator was tuned over a 20nm range for a 4V tuning voltage, the FWHM being kept below 2.5nm. Bending of membranes is a critical issue, and better results (FWHM=0.5nm) should be obtained on the same structure if this technological point is fixed.
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This paper presents a comprehensive theory and experimental characterisation of the modulation of the fluorescence intensity by the construction of optical interferences on oxidised silicon substrates used for DNA microarrays. The model predicts a 90-fold variation of the fluorescence signal depending on the oxide thickness. For a Cy3 dye, the signal is maximal for a 90 nm oxide thickness corresponding to a 7.5-fold enhancement with respect to a standard glass substrate. For experimental validation of the model, we have prepared Si/SiO2 substrates with different parallel steps of decreasing oxide thicknesses on the same sample using a buffered oxide etch (BOE) etching process after thermal oxidation. The SiO2 surface has been functionalized by a silane monolayer before in situ synthesis of L185 oligonucleotide probes. After hybridisation with complementary targets, the variations of the fluorescence intensity versus oxide thickness are in very good accordance with the theoretical model. The experimental comparison against a glass substrate shows a 10-fold enhancement of the detection sensitivity. Our results demonstrate that a Si/SiO2 substrate is an attractive alternative to standard glass slides for the realisation of fluorescence DNA microarrays whenever detection sensitivity is an important issue.
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Materiales Biocompatibles Revestidos/química , Diseño Asistido por Computadora , Modelos Químicos , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Dióxido de Silicio/química , Silicio/química , Espectrometría de Fluorescencia/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Fluorescencia/métodosRESUMEN
The introduction of exogenous wild-type p53 into human cancer cells bearing p53 mutation does not necessarily result in inhibition of tumor growth. We have demonstrated this in MDA-MB468 breast cancer cells which are hemizygous for p53 mutation and also in KM12SM colorectal carcinoma cells which are heterozygous for p53 mutation. The wtp53 transfectants decreased three- to four-fold the number of colonies compared with controls. Most wtp53-expressing cells died by apoptosis at early passages, but some cells were able to form colonies and their proliferation rate was similar to control transfectants. This reversion was observed in three of the six MDA-MB-468 clones selected. When MDA-wtp53 transfectants were implanted orthotopically in nude mice only one clone showed prolonged tumor latency. No differences were found in either tumor proliferation or apoptosis in tumors. Integration and expression of exogenous wtp53 was assessed in early and late passages in vitro, and in tumors growing in vivo. Consistently, we found mutations in the exogenous wtp53 gene of MDA-MB468 transfectants. Excision of the exogenous gene was an alternative to abrogate the wtp53 function that was extremely efficient in KM12 cells, although they maintained resistance to geneticin. These results were corroborated by the functional assay in yeast. In conclusion, wtp53 is inactivated in these cancer cells by different mechanisms. The presence of mutated p53 may confer genome instability and mutator ability, which allows cells to escape the effects of the exogenous wtp53 and contributes to the failure of wtp53 gene therapy.
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Neoplasias de la Mama/terapia , Neoplasias Colorrectales/terapia , Genes p53 , Terapia Genética/métodos , Transfección/métodos , Animales , Apoptosis/genética , Neoplasias de la Mama/genética , Neoplasias Colorrectales/genética , Expresión Génica , Humanos , Ratones , Ratones Desnudos , Mutación , Insuficiencia del Tratamiento , Células Tumorales CultivadasRESUMEN
Previous studies indicated that mouse transformed keratinocytes undergo an epithelial-fibroblastic conversion when cultured in the presence of TGF-beta1. This conversion is associated in vivo with a squamous-spindle carcinoma transition. We derived epithelioid (A6, FPA6) and spindle (B5) clonal cell variants from a squamous carcinoma cell line (PDV) after treatment with TGF-beta1. FPA6 cells were isolated from the ascites fluid of an A6-tumor-bearing mouse. FPA6 and A6 cell lines produced in nude mice mixed carcinomas with a squamous and poorly differentiated component. Both cell lines coexpressed keratins and vimentin and synthesized E-cadherin protein, although FPA6 cells cultured at early passages (FPA6-ep) had reduced levels of E-cadherin mRNA and increased synthesis of keratin K8, a marker of malignant progression. Immunofluorescence analysis revealed that FPA6-ep cells exhibited a disorganized cytoskeleton with keratins forming focal juxtanuclear aggregates and loss of F-actin stress fibers and cortical bundles, and E-cadherin was localized in the cytoplasm out of cell-cell contact areas. Sporadic cells in A6 and PDV cultures also presented those anomalous keratin structures, suggesting that FPA6 cells originated from a subpopulation of A6 tumor cells that metastasized into the peritoneal cavity. The analysis of the spontaneous and experimental metastatic potentials of the cell lines showed that epithelioid and fibroblastic cell variants had acquired metastatic abilities compared to PDV which was nonmetastatic. The FPA6-ep cell line exhibited a highly aggressive behavior, killing the animals at about 17 days after intravenous injection of the cells into athymic mice. The phenotype of FPA6-ep cells was unstable and reverted at later passages in which the normal organization of keratin and F-actin in filaments and the localization of E-cadherin at cell-cell contacts were restored. This phenotypic reversion occurred concomitantly with a reduction of the experimental metastatic potential of FPA6 cells.
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Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Transformación Celular Neoplásica/patología , Citoesqueleto/patología , Factor de Crecimiento Transformador beta/farmacología , Animales , Carcinoma de Células Escamosas/ultraestructura , Diferenciación Celular , División Celular , Transformación Celular Neoplásica/ultraestructura , Células Epiteliales/patología , Fibroblastos/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas de Neoplasias/biosíntesis , Fenotipo , Células Tumorales CultivadasRESUMEN
To assess the role of gelatinases in mouse skin tumor progression and their link to the expression of E-cadherin (E-CD), the cell-cell adhesion protein, we used the highly metastatic squamous HaCa4 cell line and several HaCa4-derived clones obtained by transfection of the mouse E-CD cDNA. Expression of matrix metalloproteinase-9 (MMP-9) mRNA and protein activity were present in E-CD (-) HaCa4 and control clones in culture, but they were strongly diminished in E-CD (+) clones (E24 and E62) at subconfluence. To explore the suppressive effect of the cell-cell contacts mediated by E-CD on MMP-9 expression, we introduced a plasmid encoding mouse E-CD antisense cDNA into the E24 cell clone. The transfectant P1-clones obtained with reduced or absent E-CD expression showed increased levels of MMP-9 gelatinase, motility in vitro, and metastatic potential in vivo. Expression of MMP-9 in the various cell clones was also negatively modulated by cell density, but this effect was much stronger in E-CD (+) cells, despite the fact that all of the cell clones analyzed maintained the expression of P-cadherin and made cell-cell contacts at high cell density. Our results indicate that in this cell system, the E-CD-mediated cell-cell contacts are involved in the down-regulation of MMP-9 expression. Thus, the loss of E-CD triggers a migratory and invasive phenotype in mouse squamous carcinoma cells.
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Cadherinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Colagenasas/metabolismo , Neoplasias Cutáneas/metabolismo , Animales , Elementos sin Sentido (Genética)/genética , Elementos sin Sentido (Genética)/farmacología , Cadherinas/genética , Carcinoma de Células Escamosas/patología , Recuento de Células , Movimiento Celular/efectos de los fármacos , Colagenasas/genética , ADN Complementario/genética , Epidermis/metabolismo , Epidermis/patología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Masculino , Metaloproteinasa 9 de la Matriz , Ratones , Ratones Endogámicos BALB C , Invasividad Neoplásica/fisiopatología , Fenotipo , Regiones Promotoras Genéticas/genética , ARN Mensajero/metabolismo , Neoplasias Cutáneas/patología , Células Tumorales CultivadasRESUMEN
To study whether sucrose administration acts on lipid mobilization during prolonged exercise, we used subcutaneous abdominal adipose tissue microdialysis in eight well-trained subjects submitted at random to two 100-min exercises (50% maximal aerobic power) on separate days. After 50 min of exercise, the subjects ingested either a sucrose solution (0.75 g/kg body wt) or water. By using a microdialysis probe, dialysate was obtained every 10 min from the subjects at rest, during exercise, and during a 30-min recovery period. During exercise without sucrose, plasma and dialysate glycerol increased significantly. With sucrose, the response was significantly lower for dialysate glycerol (P < 0.05). Plasma free fatty acid level was lower after sucrose than after water ingestion (P < 0.05). With water ingestion, plasma catecholamines increased significantly, whereas insulin fell (P < 0.05). With sucrose ingestion, the epinephrine response was blunted, whereas the insulin level was significantly increased. In conclusion, the use of adipose tissue microdialysis directly supports a lower lipid mobilization during exercise when sucrose is supplied, which confirms that the availability of carbohydrate influences lipid mobilization.
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Tejido Adiposo/metabolismo , Carbohidratos/farmacología , Lipólisis/fisiología , Esfuerzo Físico/fisiología , Adulto , Glucemia/metabolismo , Catecolaminas/sangre , Ácidos Grasos/sangre , Glicerol/sangre , Humanos , Insulina/sangre , Ácido Láctico/sangre , Movilización Lipídica/fisiología , Masculino , Microdiálisis/métodos , Persona de Mediana Edad , Sacarosa/farmacologíaRESUMEN
We have developed a novel procedure called Targeted RNA AP-PCR (TRAP-PCR) to quantitatively measure specific mRNA expression. The target mRNA is reverse transcribed using a specific primer and PCR is performed under low stringency conditions to generate a rich fingerprint-type band pattern. In this situation multiple sequences are coamplified with the targeted sequence. The amplification is carried out in a competitive fashion and is, in consequence, quantitative. We have applied this technique to determine Gelatinase A (Gel A) mRNA expression in the MXT mouse mammary carcinoma system. TRAP-PCR analysis using primers for Gel A produced a reproducible fingerprint including one major band whose identity was confirmed to be Gel A cDNA. Highly metastatic MXT subclones show an increased Gel A expression. Results were confirmed by Northern blot and protein activity (gelatin zymography). TRAP-PCR is a simple, sensitive and specific technique to comparatively quantify mRNA expression and requires less template than conventional methods.
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Gelatinasas/genética , Neoplasias Mamarias Experimentales/genética , Metaloendopeptidasas/genética , Reacción en Cadena de la Polimerasa/métodos , Animales , Northern Blotting , Femenino , Neoplasias Mamarias Experimentales/secundario , Metaloproteinasa 2 de la Matriz , Ratones , Invasividad Neoplásica , ARN Mensajero/metabolismo , Sensibilidad y Especificidad , Células Tumorales CultivadasRESUMEN
We have developed a novel murine mammary tumor system with variants representing different stages of tumor progression. The MXT-s parental cell line was established from a urethane-induced and hormone-sensitive mammary tumor. MXT-s parental cells are highly tumorigenic but poorly metastatic. MXT clones and variants were selected by either in vitro or in vivo procedures, and they differ in metastatic ability and 17 beta-estradiol dependency for tumor growth. The MXT-c1.1 and MXT-B2 cell lines produced lung metastasis after intravenous injection into 100% of syngenic mice, but only MXT-c1.1 cells were highly metastatic from intramammary tumors. The fingerprints obtained by arbitrarily primed-polymerase chain reaction demonstrated that the metastatic variants and clones had a common genetic background and resulted from clonal selection from the parental cell line. We studied whether the matrix metalloproteinase (MMP) profile is correlated with tumor progression and metastatic ability in the MXT tumor system. Gelatinases A and B were assayed in the cells, both by enzyme activity and mRNA expression. Gelatinase A was expressed in MXT-c1.1 cells, whereas MXT-B2 cells did not express either MMP. In contrast, the mammary fat pad tumors expressed both gelatinases. Membrane Type 1-MMP transcripts were also detected in MXT cells and tumors. Because the mRNA levels of gelatinase. A were low in MXT-B2 tumors, we suggested that exogenous gelatinase A bound the cell membranes of MXT-B2 cells in vivo. Indirect evidence was obtained in vitro by treatment of MXT-B2 cells with NIH/3T3 fibroblast-conditioned medium. After this treatment, we detected a gelatinolytic activity at M(r) 68,000 in the cell-membrane extract of MXT-B2 cells and an increase in migratory ability through type IV collagen matrices. On the other hand, Ha-ras gene dosage correlated positively with metastatic ability but not with either gelatinase A or gelatinase B expression. No significant differences were observed in the expression of stromelysin-1 and tissue inhibitors of MMP. Thus, in the MXT tumor system, the expression of gelatinase A or its cell association and Ha-ras gene dosage independently contribute to the metastatic phenotype.
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Gelatinasas/metabolismo , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Metaloendopeptidasas/metabolismo , Animales , División Celular/fisiología , Membrana Celular/enzimología , Células Clonales , Embrión de Mamíferos , Femenino , Gelatinasas/farmacología , Neoplasias Mamarias Experimentales/genética , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 3 de la Matriz/biosíntesis , Metaloendopeptidasas/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones SCID , Metástasis de la Neoplasia , ARN Mensajero/metabolismo , Células Tumorales Cultivadas , Vimentina/biosíntesis , Proteínas ras/metabolismoRESUMEN
Eight pairs of obese female monozygotic twins were subjected to a 4-week, very-low-calorie diet (VLCD) that induced a decrease in mean body mass index from 32.9 +/- 1.1 to 29.7 +/- 1.1 kg/m2. Infusion of the beta-adrenergic agonist, isoproterenol, induced an increase in plasma levels of nonesterified fatty acids and glycerol that was more pronounced during than before VLCD. sc fat biopsies were obtained before and during VLCD to study adipocyte lipolysis. beta-adrenergic sensitivity was moderately improved during VLCD. Basal and stimulated lipolyses, and hormone-sensitive lipase activity and protein levels were increased during VLCD. Before VLCD, intrapair resemblance was found for basal and stimulated lipolysis rates. In response to the treatment, intrapair resemblance was observed for basal lipolysis and for lipolysis stimulated with agents acting on plasma membrane receptors. These results suggest that the increase of basal lipolysis during VLCD is caused by an increase of hormone-sensitive lipase expression. They support the notion that the genotype may play a role in regulating the changes of adipose tissue lipolysis rates observed during VLCD.
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Tejido Adiposo/metabolismo , Dieta Reductora , Lipólisis , Obesidad/metabolismo , Esterol Esterasa/metabolismo , Gemelos Monocigóticos , Adrenérgicos/farmacología , Agonistas Adrenérgicos beta/farmacología , Adulto , Ingestión de Energía , Epinefrina/farmacología , Femenino , Humanos , Isoproterenol/farmacología , Persona de Mediana Edad , Obesidad/dietoterapiaRESUMEN
BACKGROUND: During spaceflight, changes in the cardiovascular system and in pulmonary mechanics take place but no apparent impairment of respiratory function occurs. However, little is known about the first hours in microgravity. HYPOTHESIS: The changes occurring at the same time in the cardiovascular and pulmonary systems could interact and lead to a transient impairment of blood gases at the onset of microgravity. METHODS: Cardiovascular and respiratory changes were studied during 6 degrees head-down tilt (HDT), a now well-known method for simulation of microgravity. After a baseline standing position, 10 men were exposed to 4 h of 6 degrees HDT. Hemodynamic parameters were measured by thoracic electrical bioimpedance. Ventilatory parameters were studied by spirographic measurements and mass spectrometer analysis of expired gases. Arterial blood parameters were analyzed by specific electrodes. RESULTS: Immediately after tilting, stroke volume and cardiac output increased, as measured by thoracic bio-impedance, while heart rate and thoracic fluid index decreased. Blood gas analysis showed hypercapnia, acidosis and a tendency to hypoxia. These changes were related to hypoventilation shown by the decrease in minute ventilation. After usually less than 30 min, all the parameters reached a steady state. Return to the standing position provoked reverse variations with orthostatic intolerance in 4 subjects. CONCLUSION: Marked changes in both the cardiovascular and respiratory systems occur within the first minutes of HDT (i.e., transition to simulated microgravity).
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Inclinación de Cabeza/fisiología , Hemodinámica/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Ventilación Pulmonar/fisiología , Simulación de Ingravidez/efectos adversos , Adulto , Análisis de los Gases de la Sangre , Humanos , Masculino , Factores de TiempoRESUMEN
The HaCa4 cell line, derived from a mouse skin carcinoma induced by Harvey murine sarcoma virus, is highly tumorigenic when injected into nude mice and produces multiple metastases in the lungs. HaCa4 cells express high levels of viral Ha-ras oncogene products, anomalously synthesize the embryonic/simple epithelial keratin K8, and have lost the expression of the cell-cell adhesion receptor E-cadherin (E-CD). E-CD(+) cell clones (E62 and E24), obtained by transfection of an exogenous E-CD cDNA into HaCa4 cells, had a decreased ability to migrate through type IV collagen matrices. However, the E-CD (+) E62 clone remained as metastatic as the parental cell line, whereas the E24 clone, which does not take up the exogenous cDNA but spontaneously switches on the endogenous E-CD gene, suppressed the metastatic phenotype although it maintained its tumorigenicity. E24 cells had fivefold to sixfold lower levels of viral Ha-ras mRNA and p21 protein than the other cell lines. In addition, they did not synthesize K8 but rather switched on keratin K19. The comparison of E-CD proteins synthesized by E62 and E24 cell lines revealed no structural or functional differences because both localized at cell-cell contacts and associated with alpha-catenin, beta-catenin, and plakoglobin. Furthermore, E-CD was still expressed in metastatic lung nodules produced by E62 cells. These results suggest that suppression of the metastatic phenotype in E24 cells occurs independently of E-CD expression and correlates with decreased levels of the oncogenic ras p21 protein.
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Cadherinas/biosíntesis , Genes ras , Metástasis de la Neoplasia/genética , Proteínas Proto-Oncogénicas p21(ras)/biosíntesis , Neoplasias Cutáneas/patología , Animales , Northern Blotting , Línea Celular , Quimiotaxis , ADN Complementario , Electroforesis en Gel de Poliacrilamida , Expresión Génica , Virus del Sarcoma Murino de Harvey , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/biosíntesis , Proteínas de Filamentos Intermediarios/aislamiento & purificación , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Metionina/metabolismo , Ratones , Ratones Desnudos , Fenotipo , ARN Mensajero/biosíntesis , Proteínas Recombinantes/biosíntesis , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Transfección , Células Tumorales CultivadasRESUMEN
Matrigel, a reconstituted extract of basement membrane, enhances the growth of different human cancer cell lines when transplanted into nude mice. Here that stimulation was confirmed in the BALB/c murine mammary-tumor cell line M3MC, as well as in human colon (SW948) and mammary (MDA-MB-468) carcinoma cell lines transplanted in nude and SCID mice, respectively. Subcutaneous and intra-mammary fat-pad inoculations of Matrigel alone generated an angiogenic response which was macroscopically evident by day 9. Histological analysis of the local host reaction occurring at the site of injection revealed an early peripheral fibroblast response, followed by mononuclear cell infiltration, solid and hollow fibroblast cords projections from the edge to the center of the Matrigel plug, and finally capillary ingrowths. Conditioned media obtained from the gels generated in vivo, acted as very strong chemoattractants for mouse lung capillary endothelial cells, stimulating their motility between 38 and 82 times with respect to the control. Our results suggest an important role of host cells recruited by Matrigel, which could favor angiogenesis of the area and thus facilitate the growth of tumor cells co-inoculated with the basement membrane extract.
Asunto(s)
Colágeno/toxicidad , Laminina/toxicidad , Neoplasias Experimentales/irrigación sanguínea , Neoplasias/irrigación sanguínea , Neovascularización Patológica , Proteoglicanos/toxicidad , Adenocarcinoma/irrigación sanguínea , Adenocarcinoma/enzimología , Adenocarcinoma/patología , Animales , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , División Celular/efectos de los fármacos , Quimiotaxis/efectos de los fármacos , Colágeno/metabolismo , Colagenasas/metabolismo , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Combinación de Medicamentos , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Femenino , Humanos , Neoplasias Mamarias Experimentales/irrigación sanguínea , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Metaloproteinasa 9 de la Matriz , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias/enzimología , Neoplasias/patología , Neoplasias Experimentales/enzimología , Neoplasias Experimentales/patología , Estimulación Química , Células Tumorales CultivadasRESUMEN
GH deficiency impairs lipid metabolism in adults, but little is known about the direct effect of GH on adipose tissue in humans. First, the in vitro response of fat cells to GH in five GH-deficient adults was studied; second, it was investigated whether 6-month recombinant human GH (rhGH) administration modifies this response. Biopsies of fat were obtained from the periumbilical region before and after rhGH administration. The response of the collagenase-isolated fat cells to various concentrations of GH was assessed by glycerol release, measured by bioluminescence. Before treatment, GH induced a lipolytic activity from the adipocytes, which became significantly higher after 6 months of treatment. Thus, this study provides evidence for an intrinsic lipolytic activity of GH in GH-deficient adults and for its improvement after long term rhGH administration.