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1.
Allergy ; 72(3): 473-482, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27624865

RESUMEN

RATIONALE: Genetic polymorphisms in the asthma susceptibility gene, urokinase plasminogen activator receptor (uPAR/PLAUR) have been associated with lung function decline and uPAR blood levels in asthma subjects. Preliminary studies have identified uPAR elevation in asthma; however, a definitive study regarding which clinical features of asthma uPAR may be driving is currently lacking. OBJECTIVES: We aimed to comprehensively determine the uPAR expression profile in asthma and control subjects utilizing bronchial biopsies and serum, and to relate uPAR expression to asthma clinical features. METHODS: uPAR levels were determined in control (n = 9) and asthmatic (n = 27) bronchial biopsies using immunohistochemistry, with a semi-quantitative score defining intensity in multiple cell types. Soluble-cleaved (sc) uPAR levels were determined in serum through ELISA in UK (cases n = 129; controls n = 39) and Dutch (cases n = 514; controls n = 96) cohorts. MEASUREMENTS AND MAIN RESULTS: In bronchial tissue, uPAR was elevated in inflammatory cells in the lamina propria (P = 0.0019), bronchial epithelial (P = 0.0002) and airway smooth muscle cells (P = 0.0352) of patients with asthma, with uPAR levels correlated between the cell types. No correlation with disease severity or asthma clinical features was identified. scuPAR serum levels were elevated in patients with asthma (1.5-fold; P = 0.0008), and we identified an association between high uPAR serum levels and severe, nonatopic disease. CONCLUSIONS: This study provides novel data that elevated airway and blood uPAR is a feature of asthma and that blood uPAR is particularly related to severe, nonatopic asthma. The findings warrant further investigation and may provide a therapeutic opportunity for this refractory population.


Asunto(s)
Asma/diagnóstico , Asma/metabolismo , Receptores del Activador de Plasminógeno Tipo Uroquinasa/metabolismo , Mucosa Respiratoria/metabolismo , Asma/sangre , Asma/etiología , Biomarcadores , Biopsia , Bronquios/metabolismo , Bronquios/patología , Estudios de Casos y Controles , Femenino , Expresión Génica , Humanos , Hipersensibilidad Inmediata/genética , Hipersensibilidad Inmediata/metabolismo , Hipersensibilidad Inmediata/patología , Inmunohistoquímica , Masculino , Fenotipo , Receptores del Activador de Plasminógeno Tipo Uroquinasa/sangre , Receptores del Activador de Plasminógeno Tipo Uroquinasa/genética , Pruebas de Función Respiratoria , Mucosa Respiratoria/inmunología , Índice de Severidad de la Enfermedad
2.
J Pharmacol Exp Ther ; 334(1): 137-46, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20400469

RESUMEN

Incorporation of the alpha5 nicotinic acetylcholine receptor (nAChR) subunit can greatly influence nAChR function without altering receptor number. Although few animal studies have assessed the role of the alpha5 nAChR in nicotine-mediated behaviors, recent evidence suggests an association between polymorphisms in the alpha5 nAChR gene and nicotine dependence phenotypes in humans. Thus, additional studies are imperative to elucidate the role and function of the alpha5 nAChR subunit in nicotine dependence. Using alpha5(-/-) mice, the current study aimed to examine the role of alpha5 nAChRs in the initial pharmacological effects of nicotine, nicotine reward using the conditioned place preference model, and the discriminative effects of nicotine using a two-lever drug discrimination model. (86)Rb(+) efflux and (125)I-epibatidine binding assays were conducted to examine the effect of alpha5 nAChR subunit deletion on expression and activity of functional nAChRs. Results show that alpha5(-/-) mice are less sensitive to the initial effects of nicotine in antinociception, locomotor activity, and hypothermia measures and that the alpha5 nAChR is involved in nicotine reward. Alternatively, alpha5(-/-) mice did not differ from wild-type littermates in sensitivity to the discriminative stimulus effects of nicotine. Furthermore, deletion of the alpha5 nAChR subunit resulted in a statistically significant decrease in function in the thalamus and hindbrain, but the decreases noted in spinal cord were not statistically significant. Receptor number was unaltered in all areas tested. Taken together, results of the study suggest that alpha5 nAChRs are involved in nicotine-mediated behaviors relevant to development of nicotine dependence.


Asunto(s)
Conducta Animal/efectos de los fármacos , Nicotina/farmacología , Receptores Nicotínicos/fisiología , Analgésicos Opioides/farmacología , Animales , Temperatura Corporal , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Relación Dosis-Respuesta a Droga , Hipotermia/inducido químicamente , Hipotermia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Morfina/farmacología , Actividad Motora/efectos de los fármacos , Agonistas Nicotínicos/farmacología , Dolor/metabolismo , Umbral del Dolor/efectos de los fármacos , Unión Proteica , Receptores Nicotínicos/genética , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
3.
Br J Dermatol ; 160(1): 183-5, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19016695

RESUMEN

BACKGROUND: Staphylococcal colonization of the skin is commonly observed in subjects with atopic dermatitis (AD) and correlates with disease severity. Little is known about whether the degree of T-helper 2 (Th2) polarity in these subjects can also affect the frequency of bacterial colonization in this disease. OBJECTIVES: To determine if there is a correlation between markers of Th2 polarity [serum total IgE, eosinophilia and presence of another atopic disease (allergic rhinitis)] and skin colonization with Staphylococcus aureus in subjects with AD. METHODS: A retrospective chart review was performed of an academic dermatology clinic focused on the treatment of AD with a single provider. RESULTS: Staphylococcus aureus colonization was more commonly observed in subjects with AD who had peripheral eosinophilia, elevated serum IgE levels, and/or a history of or active allergic rhinitis. CONCLUSIONS: Results suggest that Th2 polarity may enhance subjects' risk for bacterial colonization.


Asunto(s)
Dermatitis Atópica/inmunología , Piel/microbiología , Infecciones Cutáneas Estafilocócicas/inmunología , Células Th2/inmunología , Adulto , Biomarcadores/sangre , Polaridad Celular , Dermatitis Atópica/microbiología , Eosinofilia/inmunología , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Infecciones Cutáneas Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación
4.
Science ; 203(4385): 1109-10, 1979 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-17776046

RESUMEN

The mesopelagic shrimp Sergestes similis emits ventrally directed bioluminescence that closely matches the intensity of downward-directed illumination and is able to rapidly modify its light output to match changes in background intensity. Masking experiments show that the photoreceptors involved are the compound eyes or adjacent tissues. Light emission originates from modified portions of the hepatopancreas and is similar to oceanic light in angular distribution and spectral characteristics. Normally oriented animals respond minimally to upward-directed light.

5.
J Natl Cancer Inst ; 93(8): 597-604, 2001 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-11309436

RESUMEN

BACKGROUND: Intravesical chemotherapy (i.e., placement of the drug directly in the bladder) with mitomycin C is beneficial for patients with superficial bladder cancer who are at high risk of recurrence, but standard therapy is empirically based and patient response rates have been variable, in part because of inadequate drug delivery. We carried out a prospective, two-arm, randomized, multi-institutional phase III trial to test whether enhancing the drug's concentration in urine would improve its efficacy. METHODS: Patients with histologically proven transitional cell carcinoma and at high risk for recurrence were eligible for the trial. Patients in the optimized-treatment arm (n = 119) received a 40-mg dose of mitomycin C, pharmacokinetic manipulations to increase drug concentration by decreasing urine volume, and urine alkalinization to stabilize the drug. Patients in the standard-treatment arm (n = 111) received a 20-mg dose without pharmacokinetic manipulations or urine alkalinization. Both treatments were given weekly for 6 weeks. Primary endpoints were recurrence and time to recurrence. Treatment outcome was examined by use of Kaplan-Meier analysis with log-rank tests. Statistical tests were two-sided. RESULTS: Patients in the two arms did not differ in demographics or history of intravesical therapy. Dysuria occurred more frequently in the optimized arm but did not lead to more frequent treatment termination. In an intent-to-treat analysis, patients in the optimized arm showed a longer median time to recurrence (29.1 months; 95% confidence interval [CI] = 14.0 to 44.2 months) and a greater recurrence-free fraction (41.0%; 95% CI = 30.9% to 51.1%) at 5 years than patients in the standard arm (11.8 months; 95% CI = 7.2 to 16.4 months) and 24.6% (95% CI = 14.9% to 34.3%) (P =.005, log-rank test for time to recurrence). Improvements were found in all risk groups defined by tumor stage, grade, focality, and recurrence. CONCLUSIONS: This study identified a pharmacologically optimized intravesical mitomycin C treatment with statistically significantly enhanced efficacy.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Carcinoma de Células Transicionales/tratamiento farmacológico , Mitomicina/administración & dosificación , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Administración Intravesical , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitomicina/efectos adversos , Recurrencia Local de Neoplasia/prevención & control , Estudios Prospectivos , Factores de Riesgo
6.
Respir Res ; 6: 151, 2005 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-16372907

RESUMEN

BACKGROUND: Irreversible airflow obstruction in Chronic Obstructive Pulmonary Disease (COPD) is thought to result from airway remodelling associated with aberrant inflammation. Patients who experience frequent episodes of acute deterioration in symptoms and lung function, termed exacerbations, experience a faster decline in their lung function, and thus over time greater disease severity However the mechanisms by which these episodes may contribute to decreased lung function are poorly understood. This study has prospectively examined changes in sputum levels of inflammatory cells, MMP-9 and TIMP-1 during exacerbations comparing with paired samples taken prior to exacerbation. METHODS: Nineteen COPD patients ((median, [IQR]) age 69 [63 to 74], forced expiratory volume in one second (FEV1) 1.0 [0.9 to 1.2], FEV1% predicted 37.6 [27.3 to 46.2]) provided sputa at exacerbation. Of these, 12 were paired with a samples collected when the patient was stable, a median 4 months [2 to 8 months] beforehand. RESULTS: MMP-9 levels increased from 10.5 microg/g [1.2 to 21.1] prior to exacerbation to 17.1 microg/g [9.3 to 48.7] during exacerbation (P < 0.01). TIMP-1 levels decreased from 3.5 microg/g [0.6 to 7.8] to 1.5 microg/g [0.3 to 4.9] (P = 0.16). MMP-9/TIMP-1 Molar ratio significantly increased from 0.6 [0.2 to 1.1] to 3.6 [2.0 to 25.3] (P < 0.05). Neutrophil, eosinophil and lymphocyte counts all showed significant increase during exacerbation compared to before (P < 0.05). Macrophage numbers remained level. MMP-9 levels during exacerbation showed highly significant correlation with both neutrophil and lymphocyte counts (Rho = 0.7, P < 0.01). CONCLUSION: During exacerbation, increased inflammatory burden coincides with an imbalance of the proteinase MMP-9 and its cognate inhibitor TIMP-1. This may suggest a pathway connecting frequent exacerbations with lung function decline.


Asunto(s)
Recuento de Leucocitos , Metaloproteinasa 9 de la Matriz/análisis , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Esputo/citología , Esputo/inmunología , Inhibidor Tisular de Metaloproteinasa-1/análisis , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
J Leukoc Biol ; 55(1): 13-23, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7506746

RESUMEN

These studies examine the distribution of single-cell responses in basophil preparations in the context of four events that may be associated with early activation by anti-immunoglobulin E (IgE) antibody and the bacterial peptide fMet-Leu-Phe (fMLP). In general, we measured the single-cell response distributions after challenge with a concentration of stimulus that resulted in an optimal response and compared this with the distribution that occurred after challenge with suboptimal concentrations of the same stimulus. The elevation in cytosolic calcium, as detected in Fura-2-labeled basophils, after challenge with anti-IgE or fMLP showed graded characteristics in that the distributions were unimodal under conditions of optimal or suboptimal challenge with little skewing from a normal distribution. Similarly, the up-regulation of the cell surface adhesion molecule CD11b, as determined by flow cytometry, showed graded unimodal increases after challenge with anti-IgE antibody at optimal and suboptimal concentrations. In addition, stimulation of basophils led to increased F-actin polymerization. After challenge with an optimal concentration of anti-IgE antibody, the F-actin content of basophils increased to a maximum between 10 and 15 min and returned to near prechallenge levels by 60 min. There was a close correlation between the maximum increase in F-actin content and histamine release regardless of the stimulus; anti-IgE antibody, fMLP, and phorbol ester (PMA) responses lay on the same regression line. The single-cell F-actin polymerization distributions were also unimodal and graded according to the magnitude of the histamine release response. During measurements of the calcium response under the microscope we noted that basophils underwent significant changes in morphology after challenge with any stimulus. These changes were related to both degranulation and nondegranulation events and could be quantitated by a series of image-processing algorithms, which are presented. The kinetics of the morphological change, measured as a change in cell perimeter, paralleled degranulation. Single-cell distributions of the morphologic changes were also unimodal under conditions of both optimal and suboptimal stimulation. Therefore, no evidence of all-or-nothing responses could be observed in the context of these four early activation events. In general, the response distributions resembled normal distributions at both optimal and suboptimal levels of stimulation, which indicated that single basophils responded in a graded manner.


Asunto(s)
Basófilos/fisiología , Calcio/metabolismo , Degranulación de la Célula , Liberación de Histamina , Humanos , Inmunoglobulina E/inmunología , N-Formilmetionina Leucil-Fenilalanina/farmacología , Acetato de Tetradecanoilforbol/farmacología
8.
J Leukoc Biol ; 45(6): 558-71, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2470847

RESUMEN

We have examined the release of histamine and LTC4 from purified human basophils challenged with several different stimuli, both physiological and nonphysiological. Basophils (n = 16) challenged with 0.1 micrograms/ml anti-IgE released 38 +/- 4% of their available histamine and 39 +/- 12 ng LTC4/10(6) basophils within 15-30 min. F-Met peptide (n = 8) caused the release of 54 +/- 8% histamine and 42 +/- 25 ng LTC4/10(6) basophils within a period of 2-5 min. C5a caused the release of 22 +/- 3% histamine from selected donors but failed to initiate any LTC4 release unless combined with D2O or 5 mM extracellular calcium. The two nonphysiological stimuli A23187 and TPA caused extensive histamine release, 67 +/- 8 and 82 +/- 11%, respectively, and while A23187 initiated a large and rapid release of leukotriene, TPA failed to release any LTC4 even when combined with D2O or 2-5 mM extracellular calcium. Increased concentrations of extracellular calcium enhanced anti-IgE and f-Met peptide induced release of LTC4 but inhibited the A23187 induced release of leukotriene. A single peak of immunoreactive leukotriene C4 that comigrated with the authentic standard was identified using HPLC followed by radioimmunoassay. No LTD4 or LTE4 could be detected. Purified human basophils incubated with 0.2 microM [3H]AA incorporated 290 pmol/10(6) cells, or 32 +/- 5% of the available label within 60 min. The [3H]AA was taken principally into the phospholipids (73 +/- 5%), with 20 +/- 3% as neutral lipid, and only 5 +/- 2% remaining as the free acid. Three phospholipid subclasses, phosphatidylcholine, PC (24 +/- 2%), phosphatidylinositol, PI (22 +/- 1%), and phosphatidylethanolamine, PE (15 +/- 3%), accounted for the majority of the incorporated [3H]AA while the remainder of the phospholipids accounted for less than 5% of the total cpm. HPLC analysis of the lipid mediators released during stimulation with 0.1 micrograms/ml anti-IgE revealed [3H]LTC4 (2.4 +/- 1.0%), [3H]5HETE (1.0 +/- 0.1%), unmetabolized [3H]AA (91 +/- 2%), and an unidentified peak (3.4 +/- 1.4%). The unknown metabolite eluted with the prostaglandins, was inhibited by indomethacin, and appeared to have a relatively high specific activity. It may thus represent an artifact of the labeling procedure rather than a novel basophil-derived prostaglandin.


Asunto(s)
Ácidos Araquidónicos/metabolismo , Basófilos/metabolismo , Calcio/farmacología , Complemento C5/farmacología , Complemento C5a , Deuterio/farmacología , Liberación de Histamina/efectos de los fármacos , Humanos , Inmunoglobulina E/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacología , SRS-A/metabolismo , Transducción de Señal , Acetato de Tetradecanoilforbol/farmacología
9.
J Immunol Methods ; 166(1): 93-102, 1993 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-7693824

RESUMEN

Studies of human lung mast cells have usually focused on histamine release, although the enzymes stored in the granules may also contribute to the pathophysiology of the allergic response. We have used a simple colorimetric assay for tryptase to follow the release of proteolytic enzymes from human lung mast cells in vitro. Either human lung mast cell supernatants or authentic mast cell tryptase were mixed with benzoyl-DL-arginine-p-nitroaniline and incubated for up to 72 h at 37 degrees C. The appearance of nitroaniline was then measured at 410 nm in an ELISA plate reader. Cells were sonicated in H2O to measure total tryptase and histamine. Human lung mast cells contained the equivalent of 11.2 +/- 0.7 pg tryptase per cell and 3.2 +/- 0.3 pg of histamine. The amount of tryptase measured colorimetrically correlated with the level of tryptase measured by radioimmunoassay (Pharmacia), r = 0.92, P < 0.01. The inhibition profile of the proteolytic enzyme measured by the cleavage of BAPNA, was found to be identical to that of authentic lung mast cell tryptase. Over 90% of the maximum tryptase release was complete within 15 min whilst histamine release occurred within 5 min. In cells stimulated with 10 micrograms/ml anti-IgE we found a strong correlation between the release of tryptase and histamine, r = 0.95, P < 0.005. Finally, investigations with various pharmacological agents have supported our initial hypothesis that tryptase would mimic histamine release and provide an alternative marker for mast cell activation. In summary, we have utilised a simple enzymic assay as an indicator of human lung mast cell degranulation. In washed lung mast cells this assay appears be specific for granule tryptase and release of this activity into the supernatants of challenged cells correlates well with the presence of histamine. This assay offers several advantages over current methods of measuring mediator release from human lung mast cells in vitro and should provide an inexpensive and sensitive technique for following mast cell degranulation.


Asunto(s)
Colorimetría/métodos , Pulmón/enzimología , Mastocitos/enzimología , Serina Endopeptidasas/análisis , Serina Endopeptidasas/metabolismo , Benzoquinonas , Benzoilarginina-Nitroanilida , Degranulación de la Célula/efectos de los fármacos , Quimasas , Cinamatos/farmacología , Gránulos Citoplasmáticos/enzimología , Genisteína , Liberación de Histamina , Humanos , Técnicas Inmunológicas , Técnicas In Vitro , Isoflavonas/farmacología , Lactamas Macrocíclicas , Pulmón/citología , Pulmón/fisiología , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Quinonas/farmacología , Rifabutina/análogos & derivados , Sensibilidad y Especificidad , Inhibidores de Tripsina/farmacología , Triptasas
10.
J Immunol Methods ; 105(1): 107-10, 1987 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-2824619

RESUMEN

We have refined a rapid single-step Percoll technique to obtain a basophil-enriched mononuclear cell fraction suitable for further purification. Greater than 75% of the total blood basophils were recovered from a blood-Percoll interface at a purity of between 5 and 23%. The contaminating cells were principally lymphocytes with a smaller (20-25%) percentage of monocytes. Further purification using the penicillin affinity column led to the recovery of between 28 and 64% of the total blood basophils at purities ranging from 52 to 92%, a substantial improvement over our earlier protocol. There was also a marked increase in the recovery of basophils from the affinity column over our previous technique, which lead to a moderate (5-10%) increase in overall recovery.


Asunto(s)
Basófilos , Separación Celular/métodos , Humanos , Leucocitos Mononucleares , Povidona , Dióxido de Silicio
11.
Br J Pharmacol ; 99(2): 350-4, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2328399

RESUMEN

1. The relationship between the anti-inflammatory activity of the bee venom peptide 401 in the carrageenin-induced oedema of the rat hind paw and its mast cell degranulating activity has been reinvestigated. 2. Mast cell degranulation caused by compound 48/80 (10 mg kg-1) or by allergen challenge in rats sensitized to Nippostrongylus brasiliensis also suppressed rat hind paw oedema in the same test. 3. The anti-inflammatory activities of peptide 401 and compound 48/80 were partially suppressed by pretreatment of rats with mepyramine and methysergide, at doses (2.5 mg kg-1) that completely suppressed skin reactions to these mast cell-derived amines. Pretreatment of rats with compound 48/80 also suppressed the apparent anti-inflammatory actions of peptide 401 and of compound 48/80. 4. Injection of peptide 401 together with carrageenin increased the inflammatory response in the rat hind paw. 5. The anti-inflammatory activity of peptide 401 and of compound 48/80 in the carrageenin-induced swelling of the rat hind paw arises from mast cell degranulation in vivo.


Asunto(s)
Antiinflamatorios no Esteroideos , Venenos de Abeja/farmacología , Mastocitos/efectos de los fármacos , Péptidos/farmacología , p-Metoxi-N-metilfenetilamina/farmacología , Alérgenos/farmacología , Animales , Carragenina , Cimetidina/farmacología , Gránulos Citoplasmáticos/efectos de los fármacos , Edema/inducido químicamente , Edema/tratamiento farmacológico , Técnicas In Vitro , Irritantes , Masculino , Metisergida/farmacología , Nippostrongylus/inmunología , Pirilamina/farmacología , Ratas , Ratas Endogámicas
12.
Br J Pharmacol ; 119(2): 446-53, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8886433

RESUMEN

1. Okadaic acid, a cell permeant inhibitor of protein serine/threonine phosphatases (PPs), attenuated the IgE-mediated release of the pre-formed mediator, histamine from human basophils in a time- and dose-dependent manner. Optimal inhibition (77 +/- 4%, P < 0.0001) of histamine release was observed following a 2 h incubation with 1 microM okadaic acid. 2. Okadaic acid and two analogues of okadaic acid were also studied and were found to inhibit the IgE-dependent release of histamine. Concentrations required to inhibit release by 50% (IC50) were 0.6 microM for okadaic acid and 7.5 microM for okadaol, whereas okadaone was inactive. 3. The structurally-unrelated PP inhibitor, calyculin A, also inhibited IgE-dependent histamine release from basophils dose-dependently and was approximately six fold more potent than okadaic acid. 4. The IgE-mediated generation of sulphopeptidoleukotrienes (sLT) from basophils was inhibited by okadaic acid and related analogues with the following rank order of potency; okadaic acid (approx. IC50 0.3 microM) > okadaol (3 microM) > okadaone (inactive). 5. Okadaic acid, okadaol and okadaone (all at 3 microM) inhibited the IgE-mediated generation of the cytokine interleukin 4 (IL4) from human basophils by 67 +/- 9% (P < 0.002), 48 +/- 14% (P < 0.05) and 8 +/- 7% (P = 0.31), respectively. 6. Extracts of purified human basophils liberated 32P from radiolabelled glycogen phosphorylase and this PP activity was inhibited by 17 +/- 3% (P < 0.0005) by a low (2 nM) concentration of okadaic acid and was inhibited by 96 +/- 1% (P < 0.0001) by a higher (5 microM) concentration of okadaic acid. Because a low (2 nM) concentration of okadaic acid inhibits PP2A selectively whereas a higher (5 microM) concentration inhibits both PP1 and PP2A, these findings suggest that both PP1 and PP2A are present in basophils. 7. In total these data suggest that PPs are resident in human basophils and that PPs may be important in the regulation of basophil function.


Asunto(s)
Basófilos/efectos de los fármacos , Basófilos/fisiología , Inhibidores Enzimáticos/farmacología , Ácido Ocadaico/farmacología , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Basófilos/enzimología , Células Cultivadas , Liberación de Histamina/efectos de los fármacos , Humanos , Inmunoglobulina E/farmacología , Cinética , Toxinas Marinas , Oxazoles/farmacología , Monoéster Fosfórico Hidrolasas/metabolismo
13.
Biochem Pharmacol ; 41(2): 293-300, 1991 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1703413

RESUMEN

We have used the bradykinin analog, [DArg0-Hyp3-DPhe7]-bradykinin, as a model stimulus with which to examine peptide-induced mediator release from human skin mast cells (SMC) and to compare it with IgE-mediated release from the same cells. The bradykinin analog was an effective histamine secretagogue, inducing a comparable maximal level of release to that observed for anti-IgE. By contrast to anti-IgE, however, [DArg0-Hyp3-DPhe7]-bradykinin did not stimulate marked release of prostaglandin D2 (PGD2) from these cells. In experiments where cells were exposed to both stimuli simultaneously, histamine release was additive, while PGD2 release was the same as that observed for anti-IgE alone. The kinetics of [DArg0-Hyp3-DPhe7]-bradykinin-stimulated histamine release were rapid, with 50% of maximal release being achieved within 30 sec, compared to 2-3 min for anti-IgE. Interestingly, when both stimuli were applied simultaneously, the kinetics of release were intermediate between those of either stimulus alone. Studies of the signal transduction pathways that may be involved in [DArg0-Hyp3-DPhe7]-bradykinin-induced histamine release revealed striking differences to results obtained with anti-IgE. While agents that increase intracellular cyclic AMP have a pronounced inhibitory effect on IgE-mediated release, forskolin, isobutylmethylxanthine and isoproterenol were all totally ineffective at inhibiting histamine release induced by the bradykinin analog. Similarly, staurosporine, a relatively selective inhibitor of protein kinase C, and the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA) an activator of this enzyme, both have pronounced effects on IgE-mediated histamine release from SMC but were completely inactive with regard to [DArg0-Hyp3-DPhe7]-bradykinin-stimulated release. SMC stimulated with this peptide showed characteristic changes in intracellular free calcium levels, as assessed by digital video microscopy. This response differs from that induced by anti-IgE in that it had a more rapd onset, achieved a lower peak, and decayed much more rapidly. Analysis at the single cell level showed that cells that responded in this fashion upon exposure to the bradykinin analog were capable of showing an additional response upon subsequent exposure to anti-IgE. We conclude that histamine release from SMC in response to [DArg0-Hyp3-DPhe7]-bradykinin occurs via a completely different mechanism from that in response to IgE-mediated stimuli. Peptide-induced release is rapid and is not susceptible to pharmacologic manipulation of intracellular cyclic AMP or protein kinase C but utilizes a rapid transient shift in intracellular calcium concentrations as part of its signal transduction pathway.


Asunto(s)
Bradiquinina/análogos & derivados , Histamina/metabolismo , Mastocitos/metabolismo , Piel/metabolismo , Anticuerpos Antiidiotipos/farmacología , Bradiquinina/farmacología , Calcio/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Inmunoglobulina E/inmunología , Inmunoglobulina E/farmacología , Mastocitos/efectos de los fármacos , Proteína Quinasa C/metabolismo , Transducción de Señal/efectos de los fármacos , Piel/efectos de los fármacos , Sustancia P/farmacología
14.
Biochem Pharmacol ; 36(19): 3195-9, 1987 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2444228

RESUMEN

We investigated the release of the 5-lipoxygenase derivatives of arachidonic acid (AA) in purified human basophils and compared them with similar results obtained in the human lung mast cell. We have shown that purified basophils (average purity = 51 +/- 6%) challenged with 0.1 microgram/ml anti-IgE released histamine (35 +/- 9%), and LTC4 (32 +/- 10 ng/10(6) cells) but failed to release measurable quantities of immunoreactive LTB4. In contrast, the non-specific stimulus, A23187, caused the release of histamine and both LTC4 (279 +/- 95 ng/10(6) cells) and LTB4 (148 +/- 41 ng/10(6) cells). Closer analysis of the data revealed an inverse relationship between the levels of LTB4 released and the purity of the basophils, strongly suggesting that the contaminating monocytes were responsible for LTB4 synthesis. Purified human lung mast cells have been shown to release 6 ng of immunoreactive LTB4/10(6) cells, indicating that basophils release significantly less LTB4 following an IgE-mediated challenge. In a series of experiments using highly purified basophils prelabeled with [3H]AA, we demonstrated that exposure to 0.1 microgram/ml anti-IgE led to the release of [3H]LTC4, with no detectable [3H]LTB4, whereas exposure to 1.0 micrograms/ml A23187 caused the release of [3H]LTC4 and smaller quantities of [3H]LTB4, [3H]LTD4, and [3H]LTE4. We failed to detect any [3H]LTB4 in the cell pellet following challenge with either anti-IgE or A23187, indicating that LTB4 was not synthesized and retained within the cell pellet. Finally, we found that exogenously added [3H]LTB4 was not metabolized, either by basophils alone or by basophils stimulated with anti-IgE (0.1 microgram/ml).


Asunto(s)
Basófilos/metabolismo , Leucotrieno B4/biosíntesis , Calcimicina/farmacología , Liberación de Histamina , Humanos , Inmunoglobulina E/inmunología , SRS-A/biosíntesis
15.
Biochem Pharmacol ; 38(2): 227-33, 1989 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-2464345

RESUMEN

Kinins are potent proinflammatory peptides that induce histamine release from rodent mast cells. We examined the ability of bradykinin, lysylbradykinin and a series of kinin analogs to cause histamine release from human basophils, human lung mast cells and human skin mast cells. At concentrations ranging from 0.1 microM to 1 mM, bradykinin failed to cause histamine release from any of the human histamine-containing cells studied. Lysylbradykinin was also without effect on basophils and lung mast cells, but was a weak secretagogue for human skin mast cells, inducing 5.5 +/- 3% (mean +/- SD) of total cellular histamine release at a concentration of 10(-5) M. Similarly, when sixteen recently developed bradykinin antagonists were examined, these compounds had no effect on basophils or lung mast cells but all sixteen induced dose-dependent histamine release from skin mast cells. The release process was temperature dependent and, at a concentration of 10(-5) M, the antagonists induced 8-27% histamine release. Although preincubation of cells with 10(-3) M bradykinin or des(Arg9) bradykinin significantly inhibited antagonist-induced histamine release, the requirement for such high concentrations of these peptides to cause inhibition suggested that histamine release is not mediated by either B1 or B2 kinin receptors. To understand further the mechanism of histamine release, we examined a series of bradykinin analogs with single amino acid substitutions in the bradykinin sequence. Replacement of proline7 in the bradykinin sequence with D-phenylalanine is the essential change used to convert kinin analogs into antagonists, and 10(-5) M [DPhe7]-bradykinin induced 8-10% histamine release. Other analogs, devoid of antagonist activity, however, such as [DPhe6]-bradykinin and [LPhe7]-bradykinin were able to induce equivalent levels of histamine release. The ability to induce histamine release appears to be related, at least in part, to aromaticity, since [DTrp6]-bradykinin and [DTrp7]-bradykinin induced greater amounts of histamine release than equivalent [DPhe]-analogs, causing approximately 20% histamine release at 10(-5) M. By contrast, [DAla7]-bradykinin was an ineffective stimulus. In summary, a single amino acid substitution can convert bradykinin into a secretagogue for human skin mast cells. The ability of kinin analogs to induce histamine release from skin mast cells, but not lung mast cells or basophils, emphasizes the heterogeneity of human histamine-containing cells.


Asunto(s)
Bradiquinina/análogos & derivados , Liberación de Histamina/efectos de los fármacos , Basófilos/efectos de los fármacos , Bradiquinina/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Mastocitos/efectos de los fármacos , Receptores de Bradiquinina , Receptores de Neurotransmisores/efectos de los fármacos , Fenómenos Fisiológicos de la Piel , Relación Estructura-Actividad , Temperatura
16.
Neurosci Lett ; 47(1): 41-5, 1984 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-6462528

RESUMEN

Nerve growth factor (NGF) affects the development of sympathetic neurons in neonatal rodents and, at very much lower levels, stimulates fibre growth from certain neurones in culture. At levels comparable to those used in culture and found in mammalian sera, NGF has recently been shown to suppress the hindpaw oedema induced in adult rats by injection of carrageenin. On a weight basis, NGF is ten times more active in this test than dexamethasone, and a thousand times more active than the non-steroidal anti-inflammatory drug, indomethacin. It is equally effective given locally and systemically.


Asunto(s)
Antiinflamatorios/uso terapéutico , Edema/tratamiento farmacológico , Factores de Crecimiento Nervioso/uso terapéutico , Animales , Carragenina , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Miembro Posterior , Masculino , Ratas , Ratas Endogámicas
17.
Urol Clin North Am ; 18(1): 25-33, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1992572

RESUMEN

Prostate cancer is the most common type of cancer in men. Despite increased public awareness and new screening methods, a significant proportion of men continue to present with metastatic disease. Most men will respond initially to hormonal intervention; however, given time, the majority will have recurrences of hormonally unresponsive tumor on which present therapies have little impact. Research continues to identify new cellular and molecular aspects of prostate cancer with implications as possible sites of therapeutic intervention.


Asunto(s)
Neoplasias de la Próstata/tratamiento farmacológico , Animales , Antineoplásicos/uso terapéutico , Sustancias de Crecimiento/metabolismo , Sustancias de Crecimiento/fisiología , Humanos , Masculino , Oncogenes/fisiología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/fisiopatología
18.
Respir Med ; 89(4): 279-84, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7597267

RESUMEN

The efficiency (dust collection and recirculation) of a conventional upright vacuum cleaner with a prototype vacuum bag (I) with pore size of 0.1 micron was compared with a standard vacuum cleaner bag (II), in the homes of 11 atopic asthmatic subjects with a known allergy to house dust mite. Four filter vacuum cleaners were assessed in pairs-the Vax 2000 with the Vorwerk VK121 ET340 (in 10 homes), and the Nilfisk GS90 'Allergy Vac' with the Bosch maxima 43 (in nine homes). All of the selected homes were vacuumed throughout (carpets and soft furnishings) for a 15 min period with each of the cleaners, and air was sampled simultaneously at 21 min-1 (Casella personal sampler). The weight of dust retrieved was recorded, and a sample of sieved dust (2 g) and the air filters were extracted to determine the concentrations of the major allergen, Der pI, by ELISA (ALK). No significant difference was observed in either total weight of dust, or airborne and dust concentrations of Der pI between using the conventional cleaner with vacuum bags I, or vacuum bags II. The Vax and the Vorwerk filter vacuum cleaners produced no measurable airborne Der pI concentrations during use in any of the 10 homes tested, whilst the Nilfisk produced airborne Der pI in two, and the Bosch in one of the nine homes tested. The Vorwerk retrieved significantly more dust from the floors than the Vax (P < 0.002). There was no significant difference in dust retrieval between the Nilfisk and the Bosch. All of the filter vacuum cleaners investigated produced lower concentrations of airborne Der pI, compared to the conventional cleaner with or without a special dust bag. However, the amount of dust and concentration/amount of Der pI that these cleaners actually retrieved, varied and the Vorwerk appeared most effective overall.


Asunto(s)
Contaminación del Aire Interior/análisis , Alérgenos/análisis , Polvo/análisis , Artículos Domésticos/instrumentación , Ácaros/inmunología , Animales , Asma/prevención & control , Ensayo de Inmunoadsorción Enzimática , Filtración , Humanos
19.
J R Soc Med ; 78(1): 35-8, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3968669

RESUMEN

A detailed analysis of the occupancy of a new recovery room in a small district general hospital was undertaken during the initial three months of its use. The main problems were found to be irregular workload, consistently high patient occupancy over lunchtime, and difficulty in matching traditional nursing shifts to periods of heavy workload.


Asunto(s)
Ocupación de Camas , Sala de Recuperación , Hospitales de Distrito , Hospitales Generales , Humanos , Personal de Enfermería en Hospital/organización & administración , Admisión y Programación de Personal , Sala de Recuperación/organización & administración , Escocia , Recursos Humanos
20.
Psychol Rep ; 85(1): 163-9, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10575982

RESUMEN

This study examined personality characteristics of Mexican-American male batterers. 60 Mexican-American male batterers (M = 33.6 yr.) in the court system in South Texas took the MCMI-III and their MCMI-III scores were compared with the scores of a community sample of 45 Mexican-American individuals (M = 30.4 yr.). The batterers frequently scored higher than the nonbatterers on the Avoidant and Passive-Aggressive scales, while nonbatterers frequently scored higher on the Histrionic scale. The batterers scored significantly higher on 18 out of 24 MCMI-III scales, while nonbatterers scored significantly higher on two scales.


Asunto(s)
Violencia Doméstica/etnología , Violencia Doméstica/psicología , Hispánicos o Latinos/psicología , Adulto , Cultura , Humanos , Masculino , México/etnología , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/etnología , Inventario de Personalidad , Estados Unidos
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