RESUMEN
To evaluate incidence of and risk factors for respiratory bacterial colonization and infections within 30 days from lung transplantation (LT). We retrospectively analyzed microbiological and clinical data from 94 patients transplanted for indications other than cystic fibrosis, focusing on the occurrence of bacterial respiratory colonization or infection during 1 month of follow-up after LT. Thirty-three percent of patients developed lower respiratory bacterial colonization. Bilateral LT and chronic heart diseases were independently associated to a higher risk of overall bacterial colonization. Peptic diseases conferred a higher risk of multi-drug resistant (MDR) colonization, while longer duration of aerosol prophylaxis was associated with a lower risk. Overall, 35% of lung recipients developed bacterial pneumonia. COPD (when compared to idiopathic pulmonary fibrosis, IPF) and higher BMI were associated to a lower risk of bacterial infection. A higher risk of MDR infection was observed in IPF and in patients with pre-transplant colonization and infections. The risk of post-LT respiratory infections could be stratified by considering several factors (indication for LT, type of LT, presence of certain comorbidities, and microbiologic assessment before LT). A wider use of early nebulized therapies could be useful to prevent MDR colonization, thus potentially lowering infectious risk.
Asunto(s)
Bacterias/crecimiento & desarrollo , Trasplante de Pulmón/efectos adversos , Neumonía Bacteriana/etiología , Complicaciones Posoperatorias/etiología , Infecciones del Sistema Respiratorio/etiología , Infecciones del Sistema Respiratorio/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/epidemiología , Neumonía Bacteriana/microbiología , Complicaciones Posoperatorias/microbiología , Infecciones del Sistema Respiratorio/epidemiología , Estudios Retrospectivos , Receptores de Trasplantes/estadística & datos numéricosRESUMEN
The old, red stars that constitute the bulges of galaxies, and the massive black holes at their centres, are the relics of a period in cosmic history when galaxies formed stars at remarkable rates and active galactic nuclei (AGN) shone brightly as a result of accretion onto black holes. It is widely suspected, but unproved, that the tight correlation between the mass of the black hole and the mass of the stellar bulge results from the AGN quenching the surrounding star formation as it approaches its peak luminosity. X-rays trace emission from AGN unambiguously, whereas powerful star-forming galaxies are usually dust-obscured and are brightest at infrared and submillimetre wavelengths. Here we report submillimetre and X-ray observations that show that rapid star formation was common in the host galaxies of AGN when the Universe was 2-6 billion years old, but that the most vigorous star formation is not observed around black holes above an X-ray luminosity of 10(44) ergs per second. This suppression of star formation in the host galaxy of a powerful AGN is a key prediction of models in which the AGN drives an outflow, expelling the interstellar medium of its host and transforming the galaxy's properties in a brief period of cosmic time.
RESUMEN
The extragalactic background light at far-infrared wavelengths comes from optically faint, dusty, star-forming galaxies in the Universe with star formation rates of a few hundred solar masses per year. These faint, submillimetre galaxies are challenging to study individually because of the relatively poor spatial resolution of far-infrared telescopes. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations. A previous attempt at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model. Here we report excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350 and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter haloes with a minimum mass, M(min), such that log(10)[M(min)/M(â)] = 11.5(+0.7)(-0.2) at 350 µm, where M(â) is the solar mass. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the Universe, and is lower than that predicted by semi-analytical models for galaxy formation.
RESUMEN
HLA-B*18:108 has two nucleotide changes from B*18:01:01:02 at nt 430 where A â G and nt 431 where G â A.
Asunto(s)
Alelos , Exones/genética , Sitios Genéticos , Antígenos HLA-B/genética , Intrones/genética , Análisis de Secuencia de ADN , Secuencia de Aminoácidos , Secuencia de Bases , Femenino , Antígenos HLA-B/química , Humanos , Datos de Secuencia Molecular , Alineación de SecuenciaRESUMEN
The new HLA DRB1*01:54 differs from DRB1*01:02:01 by one nucleotide at exon 2.
Asunto(s)
Alelos , Cadenas HLA-DRB1/genética , Prueba de Histocompatibilidad , Análisis de Secuencia de ADN , Secuencia de Bases , Exones/genética , Humanos , Datos de Secuencia Molecular , Alineación de SecuenciaRESUMEN
A newly identified allele, named HLA-DRB1*13:154, differs from DRB1*13:13 by the single nucleotide substitution 227T-A at codon 47 in exon 2.
Asunto(s)
Alelos , Cadenas HLA-DRB1/genética , Polimorfismo de Nucleótido Simple , Secuencia de Bases , Trasplante de Médula Ósea , Exones , Prueba de Histocompatibilidad , Humanos , Datos de Secuencia Molecular , Alineación de Secuencia , Análisis de Secuencia de ADN , Donantes de TejidosRESUMEN
Chronic prostatitis (CP) is one of the most common male urogenital diseases and a significant public health problem in industrialised countries. It is associated with a low quality of life and significant expense. Given the poor results achieved with antibiotics, scientific interest has turned to the use of natural substances with a known activity on prostate function. The aim of our study was to evaluate the effect of a new dietary supplement containing lycopene, epigallocatechin gallate, ellagic acid, selenium and zinc on semen parameters and on leucocyte concentration in seminal fluid and expressed prostate secretion (EPS) in patients with CP without infection [National Institute of Health (NIH) Category IIIA], in comparison with a control group with the same condition who did not undergo any treatment during the study period. Our data showed a statistically significant reduction in inflammatory parameters (leucocytes in seminal fluid and EPS) and a statistically significant improvement in progressive sperm motility and sperm morphology in patients treated with the supplement in comparison with the untreated group. Improvements were also seen in the pain score of the NIH-Chronic Prostatitis Symptom Index (CPSI), confirming that the reduced inflammation also resulted in a reduction in pain.
Asunto(s)
Suplementos Dietéticos , Dolor Pélvico/terapia , Semen , Adulto , Enfermedad Crónica , Femenino , Humanos , MasculinoRESUMEN
The role of two estrogen-mimicking compounds in regulating osteoblast activities were examined. Previously, our attention was focused on benzyl butyl phthalate (BBP) and di-n-butyl phthalate (DBP) since previous works showed that they enter the cytoplasm, bioaccumulate, modify actin cytoarchitecture and exert mitogenic effects involving microfilament disruption, and nuclear actin and lamin A regulation in Py1a rat osteoblasts. In this study we showed that BBP and DBP cause DNA base lesions both in MT3T3-E1 osteoblasts and in mouse primary calvarial osteoblasts (COBs). In addition, treatment with the above effectors caused an increase of p53 and phospho-p53 (ser-15 and ser-20) as well as an increase of apoptotic proteins with consequent decrease of cell viability. Moreover, treatment with phthalates did not modified p53 and phospho-p53 expression in Py1a rat osteoblasts. It is of relevance that in p53 knockdown mouse osteoblasts a proliferative effect of phthalates, similar to that observed in rat Py1a osteoblasts, was found. In conclusion, our data demonstrated that phthalates induce osteoblast apoptosis, which is, at least in part, mediated by p53 activation, suggesting that the proliferative effects could be due to p53 missing activation or p53 mutation.
Asunto(s)
Dibutil Ftalato/farmacología , Osteoblastos/efectos de los fármacos , Ácidos Ftálicos/farmacología , Plastificantes/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Supervivencia Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Procesamiento de Imagen Asistido por Computador , Ratones , Microscopía Confocal , Microscopía Inmunoelectrónica , Osteoblastos/metabolismo , Proteínas Proto-Oncogénicas c-myc/efectos de los fármacos , RatasRESUMEN
The N-methyl-D-aspartate receptor (NMDA-R) has been inter alia implicated in synaptic plasticity, brain development and emotional processes. The NMDA-R is a multiprotein complex composed of NR1, NR2 and/or NR3 subunits. We generated NR2C-2B mutant mice in which an insertion of NR2B cDNA into the gene locus of the NR2C gene replaced NR2C by NR2B expression throughout the brain. This NR2C-2B mutant was used to examine whether an NMDA-R subunit exchange in juvenile mice would affect emotional behaviors and acetylcholine (ACh), dopamine (DA) and serotonin (5-HT) content in the frontal cortex (FC) and brain structures, which are part of the brain defense system, such as the periaqueductal grey matter (PAG). Juvenile, 1-month-old NR2C-2B mice showed increased open arm avoidance in the elevated plus-maze and increased fear-induced immobility. In terms of brain neurochemistry, NR2C-2B mice showed an increase in 5-HT levels in the FC at the age of 2 months. A correlational analysis revealed that mice with low open arms avoidance had high levels of ACh in the PAG but reduced 5-HT levels in the FC. Animals which showed high levels of fear-induced immobility also had high levels of 5-HT in the FC. These results suggest that the replacement of subunit NR2C by NR2B in juvenile mice increases anxiety- and fear-related behaviors possibly due to changes in FC-5-HT and PAG-ACh levels.
Asunto(s)
Lóbulo Frontal/metabolismo , Pérdida de Tono Postural/fisiología , Desempeño Psicomotor/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Serotonina/metabolismo , Acetilcolina/metabolismo , Factores de Edad , Animales , Reacción de Prevención/fisiología , Dopamina/metabolismo , Emociones/fisiología , Conducta Exploratoria/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Sustancia Gris Periacueductal/metabolismo , Subunidades de Proteína/metabolismo , ARN Mensajero/análisis , Receptores de N-Metil-D-Aspartato/genética , Estadísticas no ParamétricasRESUMEN
N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a sensitive functional marker in heart disease, including left ventricular hypertrophy (LVH) secondary to valvular aortic stenosis (AS). We evaluated the association between NT-proBNP changes, oxidative stress, energy status and severity of LVH in patients with AS. Ten patients undergoing aortic valve replacement for AS were studied. Plasma NT-proBNP concentrations were performed by electroluminescence immunoassay 15min after the induction of anesthesia (t0), before aortic cross-clamping (t1), before clamp removal (t2), 15min after myocardial reperfusion (t3), and 24h after surgery (t4). Heart biopsies were obtained and high energy phosphates (ATP, ADP, AMP) were analyzed by capillary electrophoresis (CE). In plasma samples from the coronary sinus, nitrate plus nitrite (NOx) concentrations were also analyzed by CE. Echocardiographic measurements were acquired and correlations between biochemical markers and severity of AS were assessed. NT-proBNP peaked significantly at t4 (p<0.001). A linear correlation between NT-proBNP values measured at t0 and t4 was found (R(2)=0.89; p<0.001). A negative correlation between NT-proBNP production and phosphorylation potential (ATP/ADP ratio) was observed (R(2)=0.62; p<0.01). NOx values positively correlated with NT-proBNP levels (p<0.01). NT-proBNP inversely correlated with aortic valvular area (r=81, p<0.01), positively correlated with mean (r=0.82, p<0.01) and maximum left ventricle-to-aortic gradients (r=0.80, p<0.01), and with left ventricular mass (r=0.69, p<0.01). NT-proBNP is a useful marker of LVH and severity of AS. It may complement echocardiographic evaluation of patients with AS in identifying the optimum time for surgery.
Asunto(s)
Estenosis de la Válvula Aórtica/fisiopatología , Cardiomiopatía Hipertrófica/fisiopatología , Hipertrofia Ventricular Izquierda/fisiopatología , Daño por Reperfusión Miocárdica/fisiopatología , Péptido Natriurético Encefálico/sangre , Estrés Oxidativo , Fragmentos de Péptidos/sangre , Adenosina Difosfato/metabolismo , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/cirugía , Biomarcadores/sangre , Electroforesis Capilar , Metabolismo Energético , Circulación Extracorporea , Femenino , Paro Cardíaco Inducido , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Hipertrofia Ventricular Izquierda/metabolismo , Inmunoensayo , Mediciones Luminiscentes , Masculino , Nitratos/sangre , Nitritos/sangre , Fosforilación , Índice de Severidad de la EnfermedadRESUMEN
Eight male cattle were given a combined dose containing 20 mg/kg oxytetracycline and 0.5 mg/kg diclofenac intramuscularly. Blood samples were drawn at different times until 168 h after administration. Two experimental animals were slaughtered by humane means at weekly intervals up to 28 days after administration. Samples of muscle, injection zone tissue, liver, kidney and fat were obtained. Oxytetracycline and diclofenac concentrations were determined by high performance liquid chromatography. Kinetic analysis was performed by linear regression using the CSTRIP programme. Plasma oxytetracycline concentration showed a maximum (Cmax) of 3.89 +/- 1.48 microg/ml and a prolonged elimination half-life (T1/2beta: 47.73 +/- 18.33 h). The diclofenac plasma profile showed high Cmax (577.62 +/- 238.40 ng/ml), and its T1/2beta was also prolonged (30.48 +/- 9.42 h). Oxytetracycline concentrations were measurable in liver and adipose tissue until day 21 after administration, but all tissue samples were negative for diclofenac at 21 days. The long elimination half-life of diclofenac was an unexpected finding; its T1/2beta in humans is 1.1 h.
Asunto(s)
Antibacterianos/farmacocinética , Antiinflamatorios no Esteroideos/farmacocinética , Bovinos/metabolismo , Diclofenaco/farmacocinética , Oxitetraciclina/farmacocinética , Animales , Antibacterianos/sangre , Antiinflamatorios no Esteroideos/sangre , Área Bajo la Curva , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/veterinaria , Diclofenaco/sangre , Semivida , Inyecciones Intramusculares/veterinaria , Modelos Lineales , Masculino , Especificidad de Órganos , Oxitetraciclina/sangre , Distribución TisularRESUMEN
In Italy in the last ten years tetanus incidence has been considerably decreased. It is a result first of the application of national laws that make compulsory the tetanus vaccine for some workers' group and for the population in general, and on the other hand for the working class as a consequence of D.Lgs 626/94. It was carried out by the U.O.O.M.L. of Garbagnate an activity of sanitary surveillance towards the working class with a tetanus biological risk (i.g. builder, metalworker, cleaning staff policemen, health visitors, cooks, etc.). During this activity it was considered the possibility of a tetanus vaccine cycle for those people that couldn't provide any certification about previous tetanus vaccine. The justification for this propose is to reduce the risk of side effects due to iperimmunization in case of close vaccinations and the safety and low cost of the tritation test of antibody anti-tetanus toxin method. Therefore it was decided to determine the personal condition of tetanus immunization for all those people without a valid certification. It resulted that 38% of people subject to sanitary surveillance were not protected and 55 years people resulted to be the group with highest risk. This result was also confirmed by the Ministry of Health that considers older population the highest risk group. It becomes clear that the vaccination for working purposes protects the population in general too. In conclusion we firmly think the procedure we followed completely accomplish the general principle of healthcare for infectious risk on the application of the tit. VIII of D.Lgs. 626/94.
Asunto(s)
Anticuerpos Antibacterianos/sangre , Enfermedades Profesionales/prevención & control , Salud Laboral , Medicina del Trabajo , Toxoide Tetánico , Tétanos/prevención & control , Vacunación , Adulto , Humanos , Persona de Mediana Edad , Rol del Médico , Vigilancia de la Población , Toxoide Tetánico/inmunologíaRESUMEN
It is known that glutamatergic and cholinergic systems interact functionally at the level of the cholinergic basal forebrain. The N-methyl-d-aspartate receptor (NMDA-R) is a multiprotein complex composed of NR1, NR2 and/or NR3 subunits. The subunit composition of NMDA-R of cholinergic cells in the nucleus basalis has not yet been investigated. Here, by means of choline acetyl transferase and NR2B or NR2C double staining, we demonstrate that mice express both the NR2C and NR2B subunits in nucleus basalis cholinergic cells. We generated NR2C-2B mutant mice in which an insertion of NR2B cDNA into the gene locus of the NR2C gene replaced NR2C by NR2B expression throughout the brain. This NR2C-2B mutant was used to examine whether a subunit exchange in cholinergic neurons would affect acetylcholine (ACh) content in several brain structures. We found increased ACh levels in the frontal cortex and amygdala in the brains of NR2C-2B mutant mice. Brain ACh has been implicated in neuroplasticity, novelty-induced arousal and encoding of novel stimuli. We therefore assessed behavioral habituation to novel environments and objects as well as object recognition in NR2C-2B subunit exchange mice. The behavioral analysis did not indicate any gross behavioral alteration in the mutant mice compared with the wildtype mice. Our results show that the NR2C by NR2B subunit exchange in mice affects ACh content in two target areas of the nucleus basalis.
Asunto(s)
Acetilcolina/metabolismo , Amígdala del Cerebelo/metabolismo , Fibras Colinérgicas/metabolismo , Habituación Psicofisiológica/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Telencéfalo/metabolismo , Animales , Lóbulo Frontal/metabolismo , Masculino , Ratones , Ratones Mutantes Neurológicos , Ratones Transgénicos , Subunidades de Proteína/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Telencéfalo/citologíaRESUMEN
A partial NaCl replacement by KCl and sodium tripolyphosphate on low-fat meat sausages formulated with fish oil was studied using a mixture design. Thermal behavior by modulated differential scanning calorimetry, physicochemical, and textural properties were determined; afterwards they were mathematically modeled as a function of salts content. The thermo-rheological behavior of the different formulations was also studied in a control-stress rheometer. The optimal sodium reduction was found employing a desirability function approach. This formulation was experimentally validated and employed for microstructure analysis by environmental scanning microscopy. The results obtained in this work revealed that partial sodium replacement affected the matrix microstructure, but this change had no impact on sensory acceptability. In comparison with US and Argentinean commercial sausages, our product has 58% and 70% less Na(+) respectively.
Asunto(s)
Aceites de Pescado , Manipulación de Alimentos/métodos , Productos de la Carne/análisis , Polifosfatos , Cloruro de Potasio , Cloruro de Sodio Dietético , Sodio/análisis , Color , Comportamiento del Consumidor , Dieta con Restricción de Grasas , Dieta Hiposódica , Emulsiones , Humanos , Reología , GustoRESUMEN
We examined the effect of PGs, particularly PGF2alpha, on basic fibroblast growth factor-2 (FGF-2) messenger RNA (mRNA) and protein in the rat osteoblastic cell line Py1a and in fetal rat calvariae. Py1a cells expressed multiple FGF-2 mRNA transcripts. PGF2alpha dose-dependently increased the 6-kb transcript at 6 h. The selective PGF2alpha agonist, fluprostenol (Flup), was more potent than PGF2alpha. Phorbol myristate acetate (10(-6) M) also increased a 6-kb mRNA at 6 h. By immunofluorescence microscopy, Flup increased perinuclear staining for FGF-2 protein at 6 h and nuclear labeling at 24 h. Immunogold labeling of calvariae revealed that treatment with Flup for 3 h caused a transition of FGF expression from matrix to cells and an increase in cytoplasmic labeling for FGF-2 protein in periosteal cells and in osteoblasts. After treatment with Flup for 24 h, nuclear labeling was marked in periosteal cells and in osteoblasts, and a further increase in cytoplasmic labeling for FGF-2 was noted in osteocytes, periosteal cells, and osteoblasts. We conclude that PGs can increase FGF-2 mRNA and protein in bone cells. Because the effect of Flup was mimicked by phorbol myristate acetate, we hypothesize that PGs' regulation of FGF-2 is mediated by a PGF2alpha-selective receptor acting through protein kinase C. Hence, effects of PGs on bone remodeling may be mediated, in part, by endogenous FGF-2.
Asunto(s)
Huesos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Prostaglandinas/fisiología , Animales , Huesos/efectos de los fármacos , Huesos/ultraestructura , Células Cultivadas , Dinoprost/farmacología , Factor 2 de Crecimiento de Fibroblastos/genética , Regulación de la Expresión Génica/efectos de los fármacos , Luteolíticos/farmacología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/ultraestructura , Prostaglandinas F Sintéticas/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Two aerobic bacterial strains, a chlorophenol-degrading bacterium characterized in this work as a Ralstonia sp. LD35 on the basis of the sequence of the gene encoding for 16S ribosomal RNA, and Pseudomonas putida DSM 1868, capable of metabolizing 4-methoxybenzoic acid, were tested for their capacity to degrade monocyclic aromatic acids responsible for the toxicity of olive mill wastewaters (OMWs). Both strains possess interesting and complementary degradation capabilities in resting cell conditions: Ralstonia sp. LD35 was found to metabolize 4-hydroxybenzoic, 4-hydroxyphenylacetic, 3,4-dihydroxycinnamic and cinnamic acid, whereas DSM 1868 was capable of metabolizing 4-hydroxy-3-methoxybenzoic, 3,4-dimethoxybenzoic and 4-hydroxy-3,5-dimethoxybenzoic acid, as well as 4-hydroxybenzoic and 4-hydroxyphenylacetic acid. The kinetic parameters describing the growth of the two strains on the same compounds were determined in growing-cell batch conditions, and showed that both strains presented high affinity and high specific growth rates towards all assayed substrates. In addition, the two strains were capable of growing on and extensively biodegrading a mixture of monocyclic aromatic acids commonly found at high concentrations in OMWs, and of growing on a 20% dilution of a natural OMW. All these features make the two strains attractive candidates for the development of a biotechnological process for the biodegradation of aromatic compounds found in OMWs.
Asunto(s)
Betaproteobacteria/metabolismo , Hidrocarburos Aromáticos/metabolismo , Aceites de Plantas , Pseudomonas putida/metabolismo , Eliminación de Residuos Líquidos , Betaproteobacteria/clasificación , Betaproteobacteria/crecimiento & desarrollo , Biodegradación Ambiental , Biotecnología/métodos , Medios de Cultivo , Residuos Industriales , Aceite de Oliva , Pseudomonas putida/crecimiento & desarrolloRESUMEN
Pyrocatechase activity was studied in the Pseudomonas sp. CPE2 strain, which is capable of growing on 2-chlorobenzoic and 2,5-dichlorobenzoic acid, giving rise to catechol and 4-chlorocatechol, respectively, as intermediate metabolites. The CPE2 crude extract was found to metabolize both catechol and 4-chlorocatechol. Enzymatic as well as phenotypic studies performed both on this strain and on a mutant strain lacking the chlorocatechol-degrading genes were consistent with the presence of two catechol-cleaving enzymes, one active mainly against catechol (pyrocatechase I) and the other with broader substrate specificity (pyrocatechase II). The latter enzyme also appeared to be induced when CPE2 cells were grown on 2-chlorobenzoic acid, thus contributing to catechol metabolism, in addition to pyrocatechase I. Despite the presence of a large plasmid in CPE2 cells, the chlorocatechol-degrading genes, highly homologous to the clc operon, were located on the chromosome. The selection at relatively high frequency of mutant strains with altered growth capabilities and which lacked the chlorocatechol-degrading genes suggests a transposon-like character for these catabolic genes in the CPE2 strain.
Asunto(s)
Catecoles/metabolismo , Clorobenzoatos/metabolismo , Dioxigenasas , Oxigenasas/metabolismo , Pseudomonas/metabolismo , Biodegradación Ambiental , Southern Blotting , Catecol 1,2-Dioxigenasa , Cromatografía Líquida de Alta Presión , Conjugación Genética , ADN Bacteriano/química , Electroforesis en Gel de Agar , Mutación , Oxigenasas/genética , Plásmidos , Pseudomonas/genética , Ácido Sórbico/análogos & derivados , Ácido Sórbico/análisis , Especificidad por SustratoRESUMEN
The intracellular distribution of lectin receptor sites was studied in the rat Pyla osteoblasts using immunofluorescence at the confocal microscopy level. This immortalized cell line was found to represent a satisfactory model to study the occurrence and distribution of sugar moieties. Our data showed distinct affinity patterns of lectins recognizing different terminal or internal sugar residues. For some lectins, the binding patterns appeared to be cell cycle-independent, whereas for PNA the cell cycle greatly influenced the nuclear binding. By combining lectin affinity with sialidase degradation and alcoholic saponification the sialic acid acceptor sugars and derivatives were also visualized. In particular, glycoconjugates with sialic acids linked to beta-galactose, and mainly C4 acetylated, were located in the cytoplasm, while glycoconjugates characterized by sialic acids linked to alpha-N-acetylgalactosamine, and devoid of acetyl groups at C4, were almost exclusively found in the nucleus. The comparison of lectin affinities, with and without prior glycosidase digestions, allowed us to gain further insight into the chemical composition of glycoconjugates that act as the lectin receptor sites that appeared to belong to O- and N-linked glycoconjugates. The use of additional enzymatic treatments were useful to better establish the localization of nuclear receptor sites and results were compared with previous studies about endogenous and exogenous lectins in an attempt to reconcile the association of lectins and sugars within the nucleus and their possible involvement in modulation of cell proliferation and/or response to chemical signals. The above digestions also provided information about the cytoplasmic binding patterns.
Asunto(s)
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Osteoblastos/metabolismo , Receptores Mitogénicos/metabolismo , Sulfato de Amonio , Animales , Células Cultivadas , Colagenasas , Remoción de Radical Alquila , Desoxirribonucleasas , Hidrólisis , Lectinas , Microscopía Confocal , Neuraminidasa/química , Osteoblastos/ultraestructura , Ratas , Ribonucleasas , Fijación del Tejido , beta-GalactosidasaRESUMEN
The regional distribution and relative occurrence of phthalates were studied immunohistochemically by confocal laser scanning microscopy in the alimentary tract of the green frog, Rana esculenta, using an antibody against o-phthalate esters. Many positive sites indicating the basal presence of phthalate esters were identified. The immunoreactive cells were located in the gastric glands of the stomach and in the intestinal epithelium regions with variable frequencies. The regional distribution of phathalate-accumulating cells resembled that of fish and demonstrated that these endocrine disruptors not only enter via the alimentary canal, but also bioaccumulate inside cells specialized in secretion as well as absorption functions.