RESUMEN
The isoflavones daidzein and genistein are natural compounds which have anti-inflammatory and photoprotective activities, and may be effective in the repair of ultraviolet (UV)-induced photodamage. In this study, an alcoholic solution of aglycone isoflavones with a genistein:daidzein ratio of 1:4 [Rottapharm (RPH)-aglycone] was examined for its effects on the repair of DNA damage induced by a single dose of UVB irradiation (20 mJ/cm(2)). For this purpose, human skin cells were first UVB-irradiated and then treated with RPH-aglycone. Comet assay analysis was used to estimate the UVB-induced DNA damage at different time points after treatment by measuring the tail moment parameter. We found that treatment with 10 µmol/L RPH-aglycone solution resulted in a significantly reduced tail moment at 1h after treatment, and 34-35% enhancement of damage repair at 4 h after treatment. These results suggest that isoflavone aglycones are protective against UVB-induced DNA damage.
Asunto(s)
Anticarcinógenos/farmacología , Daño del ADN/efectos de los fármacos , Células Epidérmicas , Células Epiteliales , Genisteína/farmacología , Isoflavonas/farmacología , Rayos Ultravioleta/efectos adversos , Células Cultivadas , Ensayo Cometa , Células Epiteliales/efectos de los fármacos , Células Epiteliales/efectos de la radiación , Humanos , Envejecimiento de la Piel/efectos de los fármacosRESUMEN
The presence of dysautonomia in diabetic neuropathy is correlated with impairment of vasomotor activity that drives blood microcirculation. Microcirculation, in turn, plays an important role in thermoregulation. In this work, we investigate the changes between two different physiological conditions of diabetic patients, induced by FREMS application, in the control of skin temperature, using a minimally invasive experiment. Skin is warmed up to a fixed temperature (44 °C) for a few minutes, then the heat source is turned off, letting the skin recover its physiological temperature. Both temperature and local blood flow, the latter measured with laser Doppler, are monitored during the experiment. A simple model of the cooling phase is used to evaluate the time constants involved in the process. Results indicate that significant differences exist in the model parameters between the two conditions.
Asunto(s)
Velocidad del Flujo Sanguíneo , Regulación de la Temperatura Corporal/fisiología , Diabetes Mellitus Tipo 2/sangre , Neuropatías Diabéticas/sangre , Microcirculación/fisiología , Flujo Sanguíneo Regional/fisiología , Anciano , Femenino , Hemodinámica , Humanos , Flujometría por Láser-Doppler , Masculino , Persona de Mediana Edad , Modelos Teóricos , Distribución Normal , Temperatura Cutánea , Temperatura , Factores de TiempoRESUMEN
AIM: Aim of the study was to assess systemic effects of a cycle of treatment with a topical formulation of l-T4 and escin (Somatoline®) in healthy women based on changes in bioavailability of FT4, FT3, rT3, and TSH. METHODS: This study enrolled 20 healthy adult women with body mass index <30, not exposed to iodine-containing products. The study called for 28 consecutive days of treatment with Somatoline® followed by a 14-day follow-up period. Blood samples for FT4, FT3 and TSH levels were drawn at baseline, 5 and 24 hours after the first application and thereafter on days 14, 28 and 42. Levels of rT3 were measured during the first 24 hours postapplication. RESULTS: Subject mean age was 40.1±8.0 years and BMI from 19.1 to 29.8. Levels of FT4 always remained within normal range and did not change in a clinically relevant way from baseline (11±1.2 pg/dL), with maximum mean change from pretreatment values of 0.4 pg/mL (P=0.87). Likewise, FT3 and TSH levels did not change significantly from baseline (3±0.4 pg/dL and 1.8 ±0.9 µU/mL, respectively). Levels of rT3 behaved in a similar way, with modest changes from baseline (P=0.29). Local tolerability was defined "excellent" for 19 out of 20 women (95%) and "moderate" in one subject who experienced the onset of folliculitis, for which causal correlation with the treatment was considered "possible". CONCLUSION: Used at the posology foreseen for the marketed formulation, Somatoline® does not affect plasma levels of FT4, FT3, rT3 and TSH, either in the short term or after 28 days.
Asunto(s)
Escina/farmacocinética , Tiroxina/farmacocinética , Administración Tópica , Adolescente , Adulto , Disponibilidad Biológica , Emulsiones , Escina/administración & dosificación , Escina/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Tiroxina/administración & dosificación , Tiroxina/metabolismo , Adulto JovenAsunto(s)
Ciclooxigenasa 2 , Queratinocitos , Línea Celular , Niacina , Niacinamida , Rayos UltravioletaRESUMEN
The COVID-19 pandemic has had and is having devastating effects on the health of the population, but also on the economic health of companies and their supply chains. The old paradigms of the commercial and industrial world have been inevitably disrupted: global supply chains have shifted from a system based on efficiency to one oriented towards resilience. To this regard, the present research paper aims at investigating how Supply Chain Resilience will evolve in the new paradigms of the post-COVID business era. In order to contribute to this investigation, a semi-structured questionnaire is developed, through a structured research approach. Future research lines will be based on conducting this questionnaire as a basis for a targeted survey, analysable through association rules.
RESUMEN
PURPOSE: With evolving evidence around the progression, assessment, and management of autosomal dominant polycystic kidney disease (ADPKD), care of the disease has become increasingly complex. Needs assessments in British Columbia (BC) described variability in knowledge and comfort with incorporating these new aspects of ADPKD care into clinical practice. Undercapture of early-stage ADPKD patients in existing renal databases was also identified as an unmet need. SOURCES OF INFORMATION: A multidisciplinary group of clinicians and patient partners with interest and expertise in ADPKD and/or multidisciplinary kidney care informed the project work. An existing provincial renal database was used to support the provincial ADPKD registry. METHODS: A formalized, comprehensive provincial ADPKD Network was created within the existing infrastructure of multidisciplinary kidney clinics (MDCs) in BC. The Network is coordinated provincially and implemented locally. It incorporates robust data collection, education, creation, and dissemination of dedicated clinical tools; collaboration between clinics and clinicians across the province; and ongoing evaluation and continuous quality improvement. KEY FINDINGS: Over the 5 years since its inception, the BC ADPKD Network has enabled increased and earlier identification of British Columbians living with ADPKD and a shift in practice toward increased and earlier enrollment of ADPKD patients into MDCs. A host of tailored ADPKD clinical tools have been created and implemented in all MDCs across the province to support existing MDC staff in the delivery of more standardized and specialized ADPKD care. A collaborative provincial clinician network founded on Local Clinical Champions has been established to support ongoing experience sharing between clinics. An evaluation framework has been established to evaluate outcomes and enable ongoing refinement of the Network. LIMITATIONS: The provincial ADPKD registry is undergoing enhancements to enable more comprehensive capture of APDKD-specific information such as total kidney volume and genetic results, but at present, this remains a limitation. It remains to be seen whether the activities of the ADPKD Network will improve long-term clinical outcomes and care experiences of patients living with ADPKD, and a long-term sustainability assessment of this model of care will be required. IMPLICATIONS: The structure, tools, and coordinated and collaborative clinician network established through this comprehensive provincial ADPKD Network may be valuable in addressing the variability and gaps in existing ADPKD care while allowing patients and families across BC to receive enhanced care locally, in their usual kidney care environments.
JUSTIFICATION: L'évolution des données entourant la progression, l'évaluation et la prise en charge de la polykystose autosomique dominante (ADPKD) complexifie de plus en plus son traitement. En Colombie-Britannique (C.-B.), une évaluation des besoins a décrit la variabilité des connaissances et le niveau de confort quant à l'intégration de ces nouveaux aspects des soins pour l'ADPKD dans la pratique clinique. La capture des patients atteints d'ADPKD à un stade précoce dans les bases de données rénales existantes a également été reconnue comme un besoin non satisfait. SOURCES: Les travaux ont été orientés par un groupe multidisciplinaire de cliniciens et de patients partenaires possédant une expertise dans le domaine de l'ADPKD ou dans les soins rénaux multidisciplinaires. Une base de données provinciale existante sur les maladies rénales a été utilisée en appui au registre provincial de l'ADPKD. MÉTHODOLOGIE: Un réseau provincial complet et structuré pour l'ADPKD a été créé au sein de l'infrastructure existante des cliniques rénales multidisciplinaires (CRM) de la Colombie-Britannique. Le réseau est coordonné à l'échelle provinciale et mis en Åuvre localement. Le réseau englobe une collecte rigoureuse des données, de l'éducation, la création et la diffusion d'outils cliniques dédiés, la collaboration entre les cliniques et les cliniciens de toute la province, de même que l'évaluation et l'amélioration continues de la qualité. PRINCIPAUX RÉSULTATS: Au cours des cinq années qui ont suivi sa création, le réseau ADPKD de la C.-B. a permis d'identifier en plus grand nombre et plus précocement les Britanno-Colombiens vivant avec l'ADPKD. On a également pu observer un virage dans la pratique vers une plus vaste et une plus précoce inclusion des patients atteints d'ADPKD dans les CRM. De plus, une foule d'outils cliniques sur mesure ont été créés et mis en Åuvre dans tous les CRM de la province afin d'appuyer le personnel des CRM existantes dans la prestation de soins normalisés et plus spécialisés pour l'ADPKD. Un réseau coopératif provincial de cliniciens, fondé sur les champions cliniques locaux, a été créé pour favoriser le partage continu de l'expérience entre les cliniques. Enfin, un cadre d'évaluation a été établi pour examiner les résultats et permettre l'amélioration continue du réseau. LIMITES: Le registre provincial de l'ADPKD fait présentement l'objet d'améliorations qui permettront une saisie plus complète de l'information spécifique à l'APDKD, notamment le volume rénal total et les résultats génétiques, mais à l'heure actuelle, ceci demeure une limite. Reste à voir si les activités du réseau ADPKD permettront d'améliorer les résultats cliniques à long terme et les expériences de soins des patients vivant avec l'ADPKD. Une évaluation à long terme de la durabilité de ce modèle de soins sera nécessaire. CONCLUSION: La structure, les outils et le réseau coordonné et collaboratif de cliniciens mis en place par le biais de ce réseau provincial sur l'APDKD peuvent être utiles pour rendre compte de la variabilité et combler les lacunes des soins existantes, tout en permettant aux patients et aux familles de la Colombie-Britannique de recevoir localement de meilleurs soins, soit dans leur milieu de soins rénaux habituel.
RESUMEN
Inducible cell adhesion molecule 110 (INCAM-110) is a 110-kD glycoprotein expressed on cytokine-activated human vascular endothelial cells. mAb blocking studies indicate that INCAM-110 and intercellular adhesion molecule 1 (ICAM-1) independently support the adhesion of lymphocytes to activated human umbilical vein endothelial cell monolayers. Anti-CD11a/CD18 antibodies with anti-INCAM-110 mAb E1/6 produce greater inhibition of lymphocyte adhesion than either reagent alone, suggesting that INCAM-110 and LFA-1 are not an obligate receptor-ligand pair. Blood monocytes, but not polymorphonuclear leukocytes, also appear to bind endothelial INCAM-110. Endothelial expression of INCAM-110 is upregulated at sites of inflammation, suggesting a role in the recruitment of mononuclear leukocytes.
Asunto(s)
Antígenos CD/inmunología , Antígenos de Diferenciación/inmunología , Moléculas de Adhesión Celular/fisiología , Adhesión Celular , Endotelio Vascular/fisiología , Linfocitos/inmunología , Receptores de Adhesión de Leucocito/inmunología , Anticuerpos Monoclonales , Antígenos CD11 , Antígenos CD18 , Moléculas de Adhesión Celular/biosíntesis , Moléculas de Adhesión Celular/inmunología , Línea Celular , Endotelio Vascular/inmunología , Femenino , Citometría de Flujo , Humanos , Hipersensibilidad Tardía , Técnicas para Inmunoenzimas , Inflamación , Embarazo , Valores de Referencia , Piel/inmunología , Venas Umbilicales , Molécula 1 de Adhesión Celular VascularRESUMEN
This investigation focused on the role played by cold-insoluble globulin (CIg, plasma fibronectin) in monocyte function. Surface-bound CIg mediated a concentration-dependent of human blood monocytes to gelatin-coated surfaces. CIg also mediated the binding of gelatin-coated particles such as latex beads or tanned erythrocytes to surface-bound human monocytes. However, CIg did not mediate particle ingestion. Subfractionated CIg that was highly enriched in monomeric forms (zone II CIg, mol wt 190,000-235,000) was less effective than were fractions enriched in dimeric forms (zone I CIg, mol wt 450,000) in promoting monocyte attachment. Binding of CIg to a gelatin or plastic surface occurred in the absence of divalent cations, but monocyte attachment to CIg-coated surfaces required divalent cations, Mg++ being much more effective than Ca++. Cation-dependent cell attachment was reversible in that bound cells could be released by treatment with EDTA. Serum-mediated binding of monocytes to gelatin-coated plastic dishes was a result of its content of CIg because the binding activity was abolished by removal of CIg from serum, and could be restored by readdition of purified CIg. Treatment of monocytes with trypsin abolished subsequent cell attachment to CIg-gelatin surfaces or particles. Expression of certain other known monocyte membrane receptors (Fc and C3b) was markedly enhanced as a result of CIg-monocyte interaction. These several observations indicate that monocytes bear membrane receptors (termed receptor cold-insoluble globulin) for surface-bound CIg.
Asunto(s)
Fibronectinas/metabolismo , Monocitos/metabolismo , Receptores de Superficie Celular/metabolismo , Cationes Bivalentes , Adhesión Celular , Colágeno/metabolismo , Gelatina , Humanos , Monocitos/fisiología , Fagocitosis , Unión Proteica , Receptores de FibronectinaRESUMEN
We used a murine mAb, H4/18, raised by immunization with IL-1-treated human umbilical vein endothelial cell cultures, to localize an endothelial activation antigen in induced human delayed hypersensitivity reactions (DHR) and in pathological tissues. We used streptococcus varidase to elicit DHR in human skin and we examined sequential skin biopsies with the immunoperoxidase technique. There was no staining for H4/18 binding antigen in normal endothelium of skin and other tissues; strong positive staining, localized to vascular endothelium, was seen at 16 and 23 h but disappeared by 6 d, when the DHR had faded. H4/18 binding antigen, also confined to endothelium, was detected in lymph nodes, skin, and other tissues exhibiting immune/inflammatory reactions. The studies indicate that H4/18 is a useful marker for activated endothelium in vivo and they support the relevance of in vitro studies on inducible endothelial cell functions.
Asunto(s)
Antígenos de Superficie/biosíntesis , Endotelio/inmunología , Animales , Anticuerpos Monoclonales , Antígenos/análisis , Antígenos/biosíntesis , Antígenos de Superficie/análisis , Factores de Coagulación Sanguínea/análisis , Factores de Coagulación Sanguínea/biosíntesis , Endotelio/patología , Humanos , Hipersensibilidad Tardía/inmunología , Linfadenopatía Inmunoblástica/inmunología , Linfadenopatía Inmunoblástica/patología , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Endogámicos BALB C , Piel/irrigación sanguínea , TromboplastinaRESUMEN
Human monocyte-derived interleukin 1 (IL-1) was found to be a potent inducer of procoagulant activity in cultured human vascular endothelium. IL-1-induced human umbilical vein endothelial cell procoagulant activity (HEC-PCA) was transiently expressed, manifest in intact cell monolayers, and required protein synthesis. Data obtained with coagulation factor-deficient plasma and a goat anti-human apoprotein III antiserum suggested that most, if not all, of IL-1-induced endothelial cell procoagulant activity is tissue factor-like. IL-1 induction of HEC-PCA may be important in the pathogenesis of intravascular coagulation in a variety of immunological and inflammatory conditions.
Asunto(s)
Endotelio/metabolismo , Interleucina-1/fisiología , Tromboplastina/biosíntesis , Coagulación Sanguínea , Membrana Celular/metabolismo , Células Cultivadas , Endotelio/citología , Humanos , Monocitos/inmunología , Tromboplastina/fisiología , Venas UmbilicalesRESUMEN
Hematogenous metastasis requires the arrest and extravasation of blood-borne tumor cells, possibly involving direct adhesive interactions with vascular endothelium. Cytokine activation of cultured human endothelium increases adhesion of melanoma and carcinoma cell lines. An inducible 110-kD endothelial cell surface glycoprotein, designated INCAM-110, appears to mediate adhesion of melanoma cells. In addition, an inducible endothelial receptor for neutrophils, ELAM-1, supports the adhesion of a human colon carcinoma cell line. Thus, activation of vascular endothelium in vivo that results in increased expression of INCAM-110 and ELAM-1 may promote tumor cell adhesion and affect the incidence and distribution of metastases.
Asunto(s)
Moléculas de Adhesión Celular/fisiología , Endotelio Vascular/citología , Melanoma/patología , Animales , Anticuerpos Monoclonales , Adhesión Celular/fisiología , Moléculas de Adhesión Celular/análisis , Neoplasias del Colon/patología , Endotelio Vascular/análisis , Endotelio Vascular/fisiología , Humanos , Melanoma Experimental/patología , Peso Molecular , Células Tumorales CultivadasRESUMEN
Focal adhesion of leukocytes to the blood vessel lining is a key step in inflammation and certain vascular disease processes. Endothelial leukocyte adhesion molecule-1 (ELAM-1), a cell surface glycoprotein expressed by cytokine-activated endothelium, mediates the adhesion of blood neutrophils. A full-length complementary DNA (cDNA) for ELAM-1 has now been isolated by transient expression in COS cells. Cells transfected with the ELAM-1 clone express a surface structure recognized by two ELAM-1 specific monoclonal antibodies (H4/18 and H18/7) and support the adhesion of isolated human neutrophils and the promyelocytic cell line HL-60. Expression of ELAM-1 transcripts in cultured human endothelial cells is induced by cytokines, reaching a maximum at 2 to 4 hours and decaying by 24 hours; cell surface expression of ELAM-1 protein parallels that of the mRNA. The primary sequence of ELAM-1 predicts an amino-terminal lectin-like domain, an EGF domain, and six tandem repetitive motifs (about 60 amino acids each) related to those found in complement regulatory proteins. A similar domain structure is also found in the MEL-14 lymphocyte cell surface homing receptor, and in granule-membrane protein 140, a membrane glycoprotein of platelet and endothelial secretory granules that can be rapidly mobilized (less than 5 minutes) to the cell surface by thrombin and other stimuli. Thus, ELAM-1 may be a member of a nascent gene family of cell surface molecules involved in the regulation of inflammatory and immunological events at the interface of vessel wall and blood.
Asunto(s)
Glicoproteínas de Membrana , Neutrófilos/fisiología , Secuencia de Aminoácidos , Secuencia de Bases , Adhesión Celular , ADN/genética , Selectina E , Endotelio Vascular/metabolismo , Regulación de la Expresión Génica , Humanos , Inmunoensayo , Interleucina-1/farmacología , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Proteínas Recombinantes , Homología de Secuencia de Ácido Nucleico , Transcripción Genética , Transfección , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Endothelial leukocyte adhesion molecule-1 (ELAM-1) is an endothelial cell adhesion molecule that allows myeloid cells to attach to the walls of blood vessels adjacent to sites of inflammation. ELAM-1 recognizes the sialyl-Lewis X (sialyl-Lex) determinant, NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc-, a granulocyte carbohydrate also found on the surface of some tumor cell lines. Binding of myeloid cells to soluble ELAM-1 is inhibited by a monoclonal antibody recognizing sialyl-Lex or by proteins bearing sialyl-Lex, some of which may participate in humoral regulation of myeloid cell adhesion. Stimulated granulocytes also release an inhibitor of ELAM-1 binding that can be selectively adsorbed by monoclonal antibody to sialyl-Lex.
Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Granulocitos/metabolismo , Antígeno Lewis X/metabolismo , Neoplasias/metabolismo , Líquido Amniótico/química , Anticuerpos Monoclonales/farmacología , Secuencia de Carbohidratos , Adhesión Celular/fisiología , Moléculas de Adhesión Celular/inmunología , Membrana Celular/metabolismo , Selectina E , Endotelio Vascular/metabolismo , Fucosa/metabolismo , Fucosiltransferasas/metabolismo , Técnicas de Inmunoadsorción , Interleucina-1/farmacología , Interleucina-8/farmacología , Antígeno Lewis X/química , Datos de Secuencia Molecular , Neuraminidasa/metabolismo , Oligosacáridos/química , Orosomucoide/metabolismo , Antígeno Sialil Lewis X , Células Tumorales CultivadasRESUMEN
Human B lymphocytes localize and differentiate within the microenvironment of lymphoid germinal centers. A frozen section binding assay was developed for the identification of those molecules involved in the adhesive interactions between B cells and lymphoid follicles. Activated human B cells and B cell lines were found to selectively adhere to germinal centers. The VLA-4 molecule on the lymphocyte and the adhesion molecule INCAM-110, expressed on follicular dendritic cells, supported this interaction. This cellular interaction model can be used for the study of how B cells differentiate.
Asunto(s)
Linfocitos B/inmunología , Moléculas de Adhesión Celular/inmunología , Receptores de Antígeno muy Tardío/inmunología , Anticuerpos Monoclonales , Antígenos CD/análisis , Linfocitos B/citología , Linfocitos B/ultraestructura , Adhesión Celular , Células Cultivadas , Humanos , Tonsila Palatina/citología , Tonsila Palatina/inmunología , Bazo/inmunología , Molécula 1 de Adhesión Celular VascularRESUMEN
Crohn's disease (CD) is associated with a higher type-1-helper T cell (Th1) cytokine expression, whereas ulcerative colitis (UC) appears to express a modified Th2 response. In addition to its classic role in calcium homeostasis, calcitriol, the hormonal active form of vitamin D, exerts immunoregulatory effects such as modulation of Th1/Th2 cytokines. Therefore, calcitriol administration could modify immune dysfunction in CD and UC. Nine patients with UC (M/F: 5/4; mean age 47 years, remission(R)/active(A) disease: 7/2), 8 patients with CD (M/F: 2/6; mean age 36, R/A 5/3) and 6 healthy controls (HC) (M/F: 3/3, mean age 4) were enrolled. Peripheral blood was collected after a drug-washout of 15 days and peripheral blood mononuclear cells were stimulated with mitogens alone or in the presence of physiological concentrations of calcitriol (100 pg/ml). Type 1 (IL-2, TNF-alpha, IFN-gamma) and type 2 (IL-10) cytokine production was assayed on supernatants by ELISA. Compared to HC, TNF-alpha production was significantly higher both in UC (p=0.0002) and CD (p=0.0001) patients, at baseline and after incubation with calcitriol (UC p=0.0003, CD p=0.0009). The effects of calcitriol incubation were: 1) reduced IFN-gamma (p=0.024) and increased IL-10 (p=0.06) production in UC patients; 2) reduced TNF-alpha production in CD (p=0.032); 3) no significant effects in HC. Calcitriol increased, albeit not significantly, IL-10 production in UC compared to CD patients (p=0.09). These results suggest an important modulatory role of vitamin D in the Th1/Th2 immune response. The observation that the effect of this modulation was different in CD compared to UC patients provides an interesting area of research into the pathogenesis and treatment of these inflammatory conditions.
Asunto(s)
Calcitriol/farmacología , Citocinas/sangre , Factores Inmunológicos/farmacología , Enfermedades Inflamatorias del Intestino/inmunología , Células TH1/inmunología , Células Th2/inmunología , Adulto , Anciano , Femenino , Humanos , Activación de Linfocitos , Masculino , Persona de Mediana EdadRESUMEN
This work is an attempt to apply classification tree methods to data regarding accidents in a medium-sized refinery, so as to identify the important relationships between the variables, which can be considered as decision-making rules when adopting any measures for improvement. The results obtained using the CART (Classification And Regression Trees) method proved to be the most precise and, in general, they are encouraging concerning the use of tree diagrams as preliminary explorative techniques for the assessment of the ergonomic, management and operational parameters which influence high accident risk situations. The Occupational Injury analysis carried out in this paper was planned as a dynamic process and can be repeated systematically. The CART technique, which considers a very wide set of objective and predictive variables, shows new cause-effect correlations in occupational safety which had never been previously described, highlighting possible injury risk groups and supporting decision-making in these areas. The use of classification trees must not, however, be seen as an attempt to supplant other techniques, but as a complementary method which can be integrated into traditional types of analysis.
Asunto(s)
Accidentes de Trabajo/estadística & datos numéricos , Industria Química , Árboles de Decisión , Ergonomía/métodos , Industria Procesadora y de Extracción , Salud Laboral , Accidentes de Trabajo/clasificación , Accidentes de Trabajo/prevención & control , Humanos , Italia , Petróleo , Análisis de Regresión , Estudios RetrospectivosRESUMEN
Activation of cultured human endothelial cells (HEC) by inflammatory stimuli, such as interleukin 1 (IL-1), tumor necrosis factor (TNF), and bacterial endotoxin (lipopolysaccharide, LPS), increases their surface adhesiveness for blood leukocytes and related cell lines. We now report that activated HEC also generate a soluble leukocyte adhesion inhibitor (LAI), which accumulates in conditioned media from IL-1-, TNF-, or LPS-treated, but not sham-treated, HEC cultures. LAI significantly inhibits the adhesion of PMN and monocytes to activated, but not unactivated, HEC. In contrast, LAI has no effect on the adhesion of lymphocytes, the promyelocytic cell line HL-60 or the monocyte-like cell line U937 to HEC monolayers. LAI appears to act directly on the leukocyte, but does not inhibit either agonist-induced responses in PMN (membrane depolarization, changes in cytosolic calcium concentration, superoxide production) or PMN attachment to serum-coated plastic surfaces. Endothelial generation of LAI is blocked by actinomycin D but not by aspirin or indomethacin. Preliminary biochemical characterization indicates that LAI is a soluble, protein-containing molecule that is heat- and acid-stable. Fractionation by HPLC gel filtration yields a single peak of LAI activity (14,000 less than Mr greater than 24,000). Thus, in addition to proadhesive cell surface changes, the endothelium may also actively contribute to the regulation of endothelial-leukocyte interactions at sites of inflammation in vivo through the production of soluble adhesion inhibitors such as LAI.
Asunto(s)
Antígenos de Superficie/antagonistas & inhibidores , Endotelio Vascular/metabolismo , Endotoxinas/farmacología , Técnicas Inmunológicas , Interleucina-1/farmacología , Prueba de Inhibición de Adhesión Leucocitaria , Factor de Necrosis Tumoral alfa/farmacología , Aspirina/farmacología , Moléculas de Adhesión Celular , Células Cultivadas , Medios de Cultivo/análisis , Endotelio Vascular/citología , Humanos , Potenciales de la Membrana/efectos de los fármacos , Monocitos/efectos de los fármacos , Monocitos/fisiología , Neutrófilos/efectos de los fármacos , Neutrófilos/fisiologíaRESUMEN
We examined the effects of human interleukin 1 (IL-1) on the production of fibrinolytic components by cultured human vascular endothelium. Conditioned media collected from IL-1-treated (5 U/ml, 24 h) monolayers exhibited decreased tissue-type plasminogen activator (tPA) activity and increased plasminogen activator inhibitor (PAI) activity, as assessed by fibrin and reverse fibrin-autography. Quantitative immunological assays revealed a 35% decrease in tPA antigen and a 360% increase in active PAI antigen, after incubation for 24 h with 0.6 U/ml IL-1. Maximal effects (approximately 50% decrease in tPA antigen; 400-800% increase in active PAI antigen) were observed with 2.5-5 U/ml IL-1. Changes in tPA and PAI reached a maximum at approximately 24 h and persisted for greater than 48 h. IL-1 induction of endothelial procoagulant activity was more rapid and transient, peaking by 6 h and subsiding by 24 h. Natural monocyte-derived IL-1 and two species of recombinant IL-1 had comparable effects. Heat and polymyxin-B treatments differentiated IL-1 actions from those of endotoxin, which promoted similar endothelial alterations. IL-1 effects on endothelial procoagulant and fibrinolytic activities may contribute to the generation and maintenance of fibrin in pathophysiological settings in vivo.
Asunto(s)
Endotelio/fisiología , Fibrinólisis , Interleucina-1/fisiología , Pruebas de Coagulación Sanguínea , Células Cultivadas , Endotelio/citología , Endotelio/metabolismo , Glicoproteínas/biosíntesis , Humanos , Cinética , Inactivadores Plasminogénicos , Proteínas Recombinantes/fisiología , Activador de Tejido Plasminógeno/biosíntesis , Venas UmbilicalesRESUMEN
A series of synthetic oligosaccharides based on sialyl Lewis x (sLex; Neu5Ac alpha 2-3Gal beta 1-4[Fuc alpha 1-3]GlcNAc) and sialyl Lewis a (sLea; Neu5Ac alpha 2-3Gal beta 1-3[Fuc alpha 1-4]GlcNAc) was used to study the binding interactions of selectins. E-selectin-immunoglobulin fusion protein (E-selectin-Ig) bound to immobilized bovine serum albumin (BSA)-neoglycoproteins containing sLex or sLea in a Ca(2+)-dependent manner. Solution-phase sLex tetrasaccharide blocked this interaction by 50% at a concentration of 750 +/- 20 microM (IC50). sLea was more effective (IC50 = 220 +/- 20 microM), while nonsialylated, nonfucosylated derivatives showed little or no activity at concentrations up to 1 mM. Attachment of an 8-methoxycarbonyloctyl aglycone in a beta linkage to the anomeric carbon of the GlcNAc of sLex or sLea increased their blocking activity nearly twofold. Finally, replacement of the 2-N-acetyl substituent of the GlcNAc by an azido or amino group resulted in substantial increases in activity, with the most potent inhibitor being amino substituted sLea, which was 36-fold more active (IC50 = 21 +/- 3 microM) than the reducing tetrasaccharide sLex. In contrast to results obtained with E-selectin-Ig, P-selectin-Ig binding to immobilized BSA-sLea was blocked modestly by most oligosaccharides at 1 mM, with no substantial differences among them. IC50 values of soluble oligosaccharides determined in competitive binding studies accurately predicted blocking of leukocyte adhesion to recombinant E-selectin-Ig and to cytokine-activated endothelium.