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1.
J Synchrotron Radiat ; 30(Pt 1): 251-257, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36601944

RESUMEN

A compact spectrometer for medium-resolution resonant and non-resonant X-ray emission spectroscopy in von Hámos geometry is described. The main motivation for the design and construction of the spectrometer is to allow for acquisition of non-resonant X-ray emission spectra while measuring non-resonant X-ray Raman scattering spectra at beamline ID20 of the European Synchrotron Radiation Facility. Technical details are provided and the performance and possible use of the spectrometer are demonstrated by presenting results of several X-ray spectroscopic methods on various compounds.

2.
Occup Med (Lond) ; 70(9): 672-679, 2020 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-33269398

RESUMEN

BACKGROUND: Healthcare workers (HCWs) are commonly infected by SARS-CoV-2 and represent one of the most vulnerable groups. Adequate prevention strategies are necessary to guarantee HCWs' safety, as well as to prevent dissemination of the infection among patients. AIMS: To describe a case series of SARS-CoV-2-positive HCWs in a large public healthcare organization in Milan (Italy) during the most devastating weeks of the epidemic and analyse the sources, symptoms and duration of SARS-CoV-2 infection. METHODS: This study included 172 SARS-CoV-2-positive HCWs who were infected between the 25th of February and the 7th of April 2020. A nasopharyngeal swab (NPS) and RT-PCR were used to indicate. RESULTS: Initially, the most common sources of infection were other positive HCWs (49%). Medical doctors and nursing assistants were most frequently infected, with infection rates of 53/1000 and 50/1000, respectively. COVID-19 departments were less affected than internal medicine, surgery, intensive care, or emergency room. The most commonly reported symptom was mild cough, while loss of smell (anosmia) and loss of taste (ageusia) were reported as moderate and severe by 30-40% of HCWs. The time necessary for 50% of workers to recover from the infection was 23 days, while it took 41 days for 95% of HCWs to become virus-free. CONCLUSIONS: HCWs are commonly infected due to close contacts with other positive HCWs, and non-COVID departments were most affected. Most HCWs were asymptomatic or subclinical but contact tracing and testing of asymptomatic HCWs help identify and isolate infected workers.


Asunto(s)
Prueba de COVID-19/estadística & datos numéricos , COVID-19/diagnóstico , Personal de Salud/estadística & datos numéricos , Fuerza Laboral en Salud/estadística & datos numéricos , Exposición Profesional/estadística & datos numéricos , SARS-CoV-2/aislamiento & purificación , Adulto , COVID-19/epidemiología , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Factores de Riesgo
3.
J Tissue Eng Regen Med ; 11(8): 2204-2216, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-26756879

RESUMEN

Motivated by the success of using graphene oxide (GO) as a nanofiller of composites, there is a drive to search for this new kind of carbon material as a bioactive component in ceramic materials. In the present study, biomineralized GO was prepared by two different approaches, represented by in situ sol-gel synthesis and biomimetic treatment. It was found that in the biocomposites obtained by the sol-gel approach, the spindle-like hydroxyapatite nanoparticles, with a diameter of ca. 5 ± 0.37 nm and a length of ca. 70 ± 2.5 nm, were presented randomly and strongly on the surface. The oxygen-containing functional groups, such as hydroxyl and carbonyl, present on the basal plane and edges of the GO sheets, play an important role in anchoring calcium ions, as demonstrated by FT-IR and TEM investigations. A different result was obtained for biocomposites after biomimetic treatment: an amorphous calcium phosphate on GO sheet was observed after 5 days of treatment. These different approaches resulted in a diverse effect on the proliferation and differentiation of osteogenic mesenchymal stem cells. In fact, in biocomposites prepared by the sol-gel approach the expression of an early marker of osteogenic differentiation, ALP, increases with the amount of GO in the first days of cell culture. Meanwhile, biomimetic materials sustain cell viability and proliferation, even if the expression of alkaline phosphatase activity in a basal medium is delayed. These findings may provide new prospects for utilizing GO-based hydroxyapatite biocomposites in bone repair, bone augmentation and coating of biomedical implants and broaden the application of GO sheets in biological areas. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Huesos/metabolismo , Diferenciación Celular , Durapatita/química , Grafito/química , Células Madre Mesenquimatosas/metabolismo , Nanopartículas/química , Ingeniería de Tejidos , Huesos/citología , Humanos , Ensayo de Materiales , Células Madre Mesenquimatosas/citología
4.
Mol Cell Biochem ; 418(1-2): 49-57, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27295094

RESUMEN

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) is known to suppress NF-kB activity by interfering with its pathways. The aim of this study was to investigate the ability of 1,25(OH)2D3 in reducing the reactivation of the HIV virus J-LAT cells, an established model of latently infected cells, which were treated with TNFalpha (100 ng/ml) for 2 h with or without 24 h 1,25(OH)2D3 (100 nM) pretreatment. Reactivation of HIV RNA in J-LAT was evaluated in terms of green fluorescent protein (GFP) expression. The same experimental setting was repeated on T cells from HIV-infected patients. Treatment with TNFalpha was associated with a 16 % increase in GFP+ cells and a five-fold increase in unspliced HIV RNA expression (p < 0.04). Pretreatment of J-LAT cells with 1,25(OH)2D3 for 24 h followed by TNFalpha (100 ng/ml) for 2 h reduced the percentage of GFP+ cells by 8 %; moreover, a 2.4-fold decrease in unspliced HIV RNA expression was observed (p < 0.002). In T cells from patients, treatment with TNFalpha significantly increased unspliced HIV RNA expression (sixfold increase, p < 0.02), whereas prestimulation with 1,25(OH)2D3 reduced its expression (2.5-fold decrease, p < 0.02) compared to controls.1,25(OH)2D3 is able to reduce the ability of TNFalpha to upregulate the transcription of HIV RNA from latently infected cells. These data provide further understanding of the pathogenic mechanisms regulating viral reactivation from latent reservoirs, along with new insight in viral internalization.


Asunto(s)
Colecalciferol/farmacología , Regulación Viral de la Expresión Génica/efectos de los fármacos , Infecciones por VIH/metabolismo , VIH-1/fisiología , Factor de Necrosis Tumoral alfa/metabolismo , Activación Viral/efectos de los fármacos , Línea Celular , Humanos , ARN Viral/biosíntesis
5.
Appl Radiat Isot ; 106: 116-20, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26315099

RESUMEN

In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of alanine pellets. Monte Carlo (MC) simulations of both response of alanine and Gd-added alanine pellets with FLUKA code were performed and a good agreement was achieved for pure alanine dosimeters. For Gd2O3-alanine deviations between MC simulations and experimental data were observed and discussed.


Asunto(s)
Alanina/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Gadolinio/química , Dosificación Radioterapéutica , Humanos
6.
Eye (Lond) ; 29(10): 1347-52, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26183283

RESUMEN

PURPOSE: To investigate the long-term effect of phacoemulsification on intraocular pressure (IOP) in trabeculectomized eyes and to identify the factors affecting the IOP changes. METHODS: In consecutive patients with previous trabeculectomy (TE) who underwent uncomplicated clear cornea phacoemulsification we evaluated intraocular pressure, need of antiglaucomatous medical therapy or glaucoma surgery, and length of glaucoma control without therapy. Glaucoma therapy was prescribed in the presence of IOP >18 mm Hg or worsening of the visual field. A group of trabeculectomized eyes that did not receive cataract surgery was retrospectively selected as a control. Multivariate analysis was used to test factors related to final outcome of the treatment. RESULTS: One hundred and eight eyes with previous TE that received phacoemulsification and 108 controls were included in the study. Phacoemulsification was performed 60±21 months after TE. After a mean follow-up of 66±28 months, mean IOP was significantly increased in the cataract surgery group (by 1.7±4.3 mm Hg) and in the control group (by 2.3±4.3 mm Hg)(both P<0.001); in two groups, respectively, 31 eyes (28.7%) and 17 eyes (15.7%) had received glaucoma therapy (chi-square P=0.030). Factors related to success (no need of therapy) were use of mitomycin-C (MMC) in previous TE (P<0.001), longer time from TE to cataract surgery (P=0.007), higher preoperative bleb score (P=0.021), and lower baseline IOP (P=0.042). CONCLUSIONS: Cataract surgery reduces the function of filtering bleb in some eyes. Factors related to low rate of failure are the previous use of MMC during TE, longer time from TE to cataract surgery, and good preoperative aspect of the bleb.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Presión Intraocular/fisiología , Implantación de Lentes Intraoculares , Facoemulsificación , Malla Trabecular/fisiopatología , Trabeculectomía , Anciano , Antihipertensivos/uso terapéutico , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Campos Visuales/fisiología
7.
Radiat Prot Dosimetry ; 161(1-4): 398-402, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24591730

RESUMEN

The radiation therapy carried out by means of heavy charged particles (such as carbon ions) and neutrons is rapidly becoming widespread worldwide. The success of these radiation therapies relies on the high density of energy released by these particles or by secondary particles produced after primary interaction with matter. The biological damages produced by ionising radiations in tissues and cells depend more properly on the energy released per unit pathlength, which is the linear energy transfer and which determines the radiation quality. To improve the therapy effectiveness, it is necessary to grasp the mechanisms of free radical production and distribution after irradiation with these particles when compared with the photon beams. In this work some preliminary results on the analysis of the spatial distributions of the free radicals produced after exposure of ammonium tartrate crystals to various radiation beams ((60)Co gamma photons and thermal neutrons) were reported. Electron spin resonance analyses were performed by the electron spin echo technique, which allows the determination of local spin concentrations and by double electron-electron resonance technique, which is able to measure the spatial distance distribution (range 1.5-8 nm) among pairs of radicals in solids. The results of these analyses are discussed on the basis of the different distributions of free radicals produced by the two different radiation beams used.


Asunto(s)
Radiometría/instrumentación , Radiometría/métodos , Tartratos/química , Carbono/uso terapéutico , Radioisótopos de Cobalto/química , Cristalización , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Radicales Libres , Rayos gamma , Iones Pesados , Magnetismo , Neutrones , Fotones , Radiación Ionizante
8.
Eye (Lond) ; 28(1): 53-7, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24158022

RESUMEN

PURPOSE: To investigate the success (glaucoma control) of latanoprost therapy of primary congenital glaucoma (PCG) and factors affecting the long-term outcome. METHODS: Patients with PCG treated with latanoprost were re-examined. At study visit and from clinical charts, we evaluated: intraocular pressure, length of glaucoma control with latanoprost, need of further medication or glaucoma surgery, systemic and topical side effects. Multivariate analysis was used to test factors related to the final outcome of the treatment. RESULTS: Eighty-one eyes of 44 patients with PCG, and 42 eyes of 29 patients with previous glaucoma surgery, had received latanoprost therapy. In the first group, a success (glaucoma control by latanoprost therapy) was found in 24 eyes (29.6%), whereas 57 eyes (70.4%) had received surgery (45 eyes (55.6%) in the first year); among the eyes with previous surgery, a success was found in 12 eyes (28.6%), 13 eyes (31%) required an additional therapy, and 17 eyes (40.5%) had received further glaucoma surgery. No patient discontinued the treatment because of side effects. Factors related to the failure of the latanoprost treatment were: the high score of severity of glaucoma (P=0.014) and low age at PCG presentation (P=0.042). CONCLUSIONS: Long-term treatment with latanoprost is effective in about 30% of the eyes; factors related to failure were severe glaucomatous alterations, and young age at PCG presentation.


Asunto(s)
Antihipertensivos/uso terapéutico , Glaucoma/congénito , Glaucoma/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Prostaglandinas F Sintéticas/uso terapéutico , Antihipertensivos/efectos adversos , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Latanoprost , Masculino , Prostaglandinas F Sintéticas/efectos adversos , Estudios Retrospectivos , Tonometría Ocular , Resultado del Tratamiento
9.
Arq. bras. cardiol ; 101(2,supl.3): 1-221, ago. 2013. ilus, tab
Artículo en Portugués | LILACS | ID: lil-685382
10.
J Eur Acad Dermatol Venereol ; 27(7): 919-21, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22324638

RESUMEN

BACKGROUND: The differential diagnosis between Reed nevi and melanoma becomes more difficult if the lesion to analyse presents a small size, with a diameter of 6 mm or smaller. Many studies have reported various dermoscopic features of Reed nevi during their growth phases. In early stages of evolution, the lesions generally show a characteristic globular appearance typically found in childhood, followed by the so-called starburst pattern. OBJECTIVE: The aim of the study was to identify the main dermoscopic features in small Reed nevi (<6 mm in size). METHODS: Using a computerized skin-imaging database for melanoma prevention surgery at the Department of Dermatology of the University of Florence, 15 Reed nevi were selected among 103 small (<6 mm) melanocytic lesions consecutively excised. Images of small Reed nevi, independently blinded to histopathological diagnosis, were administered to a dermatologist expert in dermoscopy, who separately examined the clinical and the dermatoscopic images of small Reed nevi and evaluated their clinical and dermoscopic parameters. RESULTS: Analysis of the main dermoscopic patterns showed that 40% had a reticular pattern, 20% had a starburst pattern, 6.5% had a globular pattern, 6.5% had a homogeneous pattern and 27% had an atypical pattern. CONCLUSION: We propose that small, early-stage Reed nevus are not characterized by an evolution of growth patterns to a phenotype typical of larger lesions. We assume that the patterns are distributed in a linear manner between age groups, may all be present at the outset and thus are independent from the various stages of nevus development.


Asunto(s)
Dermoscopía , Nevo Pigmentado/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Adulto Joven
12.
Br J Dermatol ; 166(6): 1357-8; author reply 1358-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22098425
13.
J Steroid Biochem Mol Biol ; 127(1-2): 139-46, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21397020

RESUMEN

Food is likely to be one of the most important routes of human exposure to endocrine disrupting compounds (EDCs). In the present study, we evaluated the total estrogenic activity of fruits and vegetables, which was calculated using the human breast cancer cell line (MCF-7 BUS) proliferation assay (E-screen), in relation to pesticide residues. We analysed 44 food samples, 30 fruits and 14 vegetables. Of these samples, 10 did not contain any pesticide residues. The other 34 samples contained from 1 to 7 pesticide residues in concentrations ranging from 0.03 to 1.91 ppm. Estrogenic activity was detected in the 59% of samples tested. The positive controls used were 17-ß-estradiol (E2), the phytoestrogen genistein and the pesticide endosulfan. The average value of estradiol equivalency quantity (EEQ) for all positive samples was 0.15±0.32 µg/100g. A low correlation was found between the concentration of pesticide residues and the EEQ values (Spearman correlation r=0.376 and p=0.012). Using values obtained from the literature, we compared the estrogenic activity of food samples with the intrinsic content of phytoestrogens, but we found no correlations. Our results also suggested that the calculated intake of dietary EDCs might represent a concentration comparable to the normal endogenous estrogen concentration in human blood.


Asunto(s)
Bioensayo/métodos , Disruptores Endocrinos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Verduras/química , Línea Celular Tumoral , Femenino , Humanos
14.
Radiat Prot Dosimetry ; 147(4): 573-92, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21183550

RESUMEN

The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements.


Asunto(s)
Monitoreo de Radiación , Radiación Ionizante , Radiometría/métodos , Carga Corporal (Radioterapia) , Humanos , Dosis de Radiación , Estudios Retrospectivos , Medición de Riesgo
15.
Appl Radiat Isot ; 67(7-8 Suppl): S186-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19380235

RESUMEN

Monte Carlo numerical calculations of the response of alanine and ammonium tartrate ESR (electron spin resonance) dosimeters exposed to neutron fields with different energy spectra are reported. Results have been obtained for various gadolinium concentrations inside the dosimeters. Furthermore, in order to simulate the in-phantom response we have carried out calculations by varying the depth of the dosimeter. We have found that a large enhancement is obtained for thermal neutrons, because of the very high capture cross section of gadolinium to thermal neutrons. A good enhancement was obtained for epithermal neutrons, whereas the sensitivity improvement in the case of fast neutron irradiation is poor. Furthermore, the simulations carried out by varying the depth suggests that an appreciable sensitivity to thermal and epithermal neutrons could be observed for in-phantom measurements in the 2-3 cm depth range. These results can provide useful insight for future experiments with epithermal neutron beams (such as those used in neutron capture therapy) and for future applications in neutron capture therapy dosimetry.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/estadística & datos numéricos , Gadolinio/uso terapéutico , Terapia por Captura de Neutrón/estadística & datos numéricos , Radiometría/estadística & datos numéricos , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Alanina , Neutrones Rápidos/uso terapéutico , Humanos , Método de Montecarlo , Fantasmas de Imagen/estadística & datos numéricos , Tartratos
16.
Br J Ophthalmol ; 92(12): 1666-70, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18782799

RESUMEN

AIM: To evaluate the long-term efficacy and safety of trabeculectomy with or without low-dosage Mitomycin-C (MMC) in primary open-angle glaucoma (POAG). METHODS: 114 patients affected by POAG, participating in a randomised clinical trial from 1995 to 1998, were re-examined and their chart reviewed. Patients had undergone in one eye a trabeculectomy with intraoperative application (2 min) of MMC (0.2 mg/ml) or balanced saline solution (BSS), and, if indicated, postoperative laser suture lysis, bleb needling and/or digital massage. Intraocular pressure (IOP), medical therapy, visual field, further glaucoma surgery, cataract surgery and complication rate (leakage, cataract progression, hypotony, blebitis, endophthalmitis) were evaluated. RESULTS: 67 eyes had received MMC and 47 BSS. MMC-treated eyes had a lower mean IOP (13.33+/-3.35 vs 14.72+/-2.19 mm Hg, p = 0.014); in this group, an higher percentage of eyes had IOP < or = 18 mm Hg (73.1% vs 51.1%, p = 0.027) and IOP < or = 14 mm Hg (56.7% vs 31.9%, p = 0.015); a lower rate had further glaucoma surgery (9% vs 25.5%, p = 0.040), and visual-field damage progression (21.1% vs 48.6%, p = 0.009). No difference was seen in the complication rate: one MMC-treated eye developed blebitis. CONCLUSIONS: In POAG low-dose MMC with intensified postoperative management improved the outcome of the trabeculectomy with a low incidence of complications.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Glaucoma de Ángulo Abierto , Mitomicina/administración & dosificación , Trabeculectomía/métodos , Anciano , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Glaucoma de Ángulo Abierto/cirugía , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Modelos de Riesgos Proporcionales , Resultado del Tratamiento , Agudeza Visual/fisiología , Campos Visuales
17.
Br J Ophthalmol ; 92(11): 1479-82, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18782804

RESUMEN

AIM: To investigate the effect of 360 degrees laser retinopexy on the incidence of retinal detachment (RD) after silicone oil removal. METHODS: In a prospective, randomised clinical trial, 303 patients (303 eyes) affected with primary (n = 211) or recurring (n = 92) rhegmatogenous RD treated by vitrectomy with silicone oil (1000 cSt) and endolaser photocoagulation of retinal breaks were randomised to receive 360 degrees laser retinopexy or not. After at least 4 months, in eyes with a fully attached retina, the silicone oil was removed. The incidence of RD after silicone oil removal was evaluated. RESULTS: 151 eyes received 360 degrees laser retinopexy (completed intraoperatively in 93 eyes and postoperatively in 58 eyes, in nine of them after cataract extraction); 152 eyes served as controls. Silicone oil was removed from 139 laser-treated eyes (92.05%) and 129 controls (84.87%; NS). In the first group, 12 eyes (8.63%) developed an RD posterior to laser treatment (including the macula), three eyes (2.16%) had a localised posterior RD (treated by laser), and 14 (10.07%) had an RD anterior to the laser treatment. In the control group, RD occurred in 27 eyes (20.93%; p = 0.007). CONCLUSIONS: 360 degrees laser retinopexy reduces the incidence of RD after silicone oil removal; it should be completed intraoperatively.


Asunto(s)
Coagulación con Láser/métodos , Desprendimiento de Retina/prevención & control , Perforaciones de la Retina/prevención & control , Aceites de Silicona/uso terapéutico , Adulto , Anciano , Drenaje/métodos , Femenino , Humanos , Coagulación con Láser/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Desprendimiento de Retina/etiología , Desprendimiento de Retina/cirugía , Perforaciones de la Retina/cirugía , Aceites de Silicona/efectos adversos , Resultado del Tratamiento , Agudeza Visual/fisiología , Vitrectomía/efectos adversos , Vitrectomía/métodos
18.
Lung Cancer ; 56(1): 25-33, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17175059

RESUMEN

Interleukin-8 (IL-8; CXCL8) is a cytokine of the CXC chemokine family that is involved in neutrophil recruitment and activation. In addition, IL-8 has been implicated in a wide variety of other processes, including angiogenesis and metastasis in lung cancer. Lung adenocarcinoma and muco-epidermoid carcinoma cells produce substantial amounts of IL-8, and express both CXCR1 and CXCR2 IL-8 receptors. We hypothesized that IL-8 stimulates proliferation of non-small cell lung cancer cells, involving transactivation of the epidermal growth factor receptor (EGFR). The EGFR plays a central role in regulating cell proliferation and it has been therefore implicated in lung cancer. Both EGFR ligands and transactivation of the receptor may lead to downstream signalling events, including mitogen-activated protein kinase (MAPK) activation. Transactivation of the EGFR has been shown to occur in response to ligands of various G-protein coupled receptors (GPCRs) and involves metalloproteinase-mediated release of membrane bound EGFR ligands. The aim of the present study was to investigate the effect of IL-8 on proliferation of lung adenocarcinoma and muco-epidermoid carcinoma cells, and to explore the mechanisms leading to this proliferation in two different non-small cell lung cancer cell lines (A549 and NCI-H292). In both NSCLC cell lines, we observed that IL-8 stimulates epithelial cell proliferation in a dose-dependent manner. The ability of IL-8 to increase cell proliferation was blocked both by an inhibitor of EGFR tyrosine kinase, by a specific anti-EGFR blocking antibody and by a panmetalloproteinase inhibitor. Similar results were obtained using the GPCR inhibitor pertussis toxin. Inhibition of the MAPK p42/44 (ERK1/2) also blocked the mitogenic effect of IL-8, while a p38 MAPK inhibitor did not affect IL-8-induced cell proliferation. These results suggest that IL-8 increases cell proliferation in NSCLC cell lines via transactivation of the EGFR and that this mechanism involves metalloproteinase activity.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Receptores ErbB/metabolismo , Interleucina-8/farmacología , Neoplasias Pulmonares/metabolismo , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Luminiscencia , Neoplasias Pulmonares/patología , Metaloproteasas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal , Activación Transcripcional , Células Tumorales Cultivadas
20.
Colorectal Dis ; 5(4): 304-10, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12814406

RESUMEN

An international working party with experience in the performance of an alternative haemorrhoid operation through the use of the circular stapler was convened for the purpose of developing a consensus as to the criteria for undertaking this procedure. The agenda consisted of first, naming the operation; second, the indications and contra-indications for its performance; and third, the preferred surgical technique. Among the recommendations for individuals who plan to embark on this surgery are that experience with anorectal surgery and an understanding of anorectal anatomy are requisites; experience with circular stapling devices is essential; and the surgeon must attend a formal course which should include lectures, videos, the application of the instrument in models, and observation of the operation as performed by a surgeon recognized by his or her peers-leading ultimately to undertaking the procedure while being observed by an experienced surgeon. Following satisfactory completion of the above, independent responsibility should be determined by an individual's department of surgery.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Hemorroides/cirugía , Grapado Quirúrgico , Humanos , Grapado Quirúrgico/métodos
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