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1.
Heliyon ; 10(8): e29356, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38644898

RESUMEN

Landfills play a key role as greenhouse gas (GHGs) emitters, and urgently need assessment and management plans development to swiftly reduce their climate impact. In this context, accurate emission measurements from landfills under different climate and management would reduce the uncertainty in emission accounting. In this study, more than one year of long-term high-frequency data of CO2 and CH4 fluxes were collected in two Italian landfills (Giugliano and Case Passerini) with contrasting management (gas recovery VS no management) using eddy covariance (EC), with the aim to i) investigate the relation between climate drivers and CO2 and CH4 fluxes at different time intervals and ii) to assess the overall GHG balances including the biogas extraction and energy recovery components. Results indicated a higher net atmospheric CO2 source (5.7 ± 5.3 g m2 d-1) at Giugliano compared to Case Passerini (2.4 ± 4.9 g m2 d-1) as well as one order of magnitude higher atmospheric CH4 fluxes (6.0 ± 5.7 g m2 d-1 and 0.7 ± 0.6 g m2 d-1 respectively). Statistical analysis highlighted that fluxes were mainly driven by thermal variables, followed by water availability, with their relative importance changing according to the time-interval considered. The rate of change in barometric pressure (dP/dt) influenced CH4 patterns and magnitude in the classes ranging from -1.25 to +1.25 Pa h-1, with reduction when dP/dt > 0 and increase when dP/dt < 0, whilst a clear pattern was not observed when all dP/dt classes were analyzed. When including management, the total atmospheric GHG balance computed for the two landfills of Giugliano and Case Passerini was 174 g m2 d-1 and 79 g m2 d-1 respectively, of which 168 g m2 d-1 and 20 g m2 d-1 constituted by CH4 fluxes.

2.
Plant Biol (Stuttg) ; 25(4): 518-528, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36942418

RESUMEN

Rising daily temperatures and water shortage are two of the major concerns in agriculture. In this work, we analysed the tolerance traits in a tomato line carrying a small region of the Solanum pennellii wild genome (IL12-4-SL) when grown under prolonged conditions of single and combined high temperature and water stress. When exposed to stress, IL12-4-SL showed higher heat tolerance than the cultivated line M82 at morphological, physiological, and biochemical levels. Moreover, under stress IL12-4-SL produced more flowers than M82, also characterized by higher pollen viability. In both lines, water stress negatively affected photosynthesis more than heat alone, whereas the combined stress did not further exacerbate the negative impacts of drought on this trait. Despite an observed decrease in carbon fixation, the quantum yield of PSII linear electron transport in IL12-4-SL was not affected by stress, thereby indicating that photochemical processes other than CO2 fixation acted to maintain the electron chain in oxidized state and prevent photodamage. The ability of IL12-4-SL to tolerate abiotic stress was also related to the intrinsic ability of this line to accumulate ascorbic acid. The data collected in this study clearly indicate improved tolerance to single and combined abiotic stress for IL12-4-SL, making this line a promising one for cultivation in a climate scenario characterized by frequent and long-lasting heatwaves and low rainfall.


Asunto(s)
Solanum lycopersicum , Solanum , Solanum lycopersicum/genética , Solanum/genética , Deshidratación , Estrés Fisiológico/genética , Interleucina-12
3.
Plant Biol (Stuttg) ; 24(1): 62-74, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34605594

RESUMEN

Climate change is increasing the frequency of high temperature shocks and water shortages, pointing to the need to develop novel tolerant varieties and to understand the mechanisms employed to withstand combined abiotic stresses. Two tomato genotypes, a heat-tolerant Solanum lycopersicum accession (LA3120) and a novel genotype (E42), previously selected as a stable yielding genotype under high temperatures, were exposed to single and combined water and heat stress. Plant functional traits, pollen viability and physiological (leaf gas exchange and chlorophyll a fluorescence emission measurements) and biochemical (antioxidant content and antioxidant enzyme activity) measurements were carried out. A Reduced Representation Sequencing approach allowed exploration of the genetic variability of both genotypes to identify candidate genes that could regulate stress responses. Both abiotic stresses had a severe impact on plant growth parameters and on the reproductive phase of development. Growth parameters and leaf gas exchange measurements revealed that the two genotypes used different physiological strategies to overcome individual and combined stresses, with E42 having a more efficient capacity to utilize the limiting water resources. Activation of antioxidant defence mechanisms seemed to be critical for both genotypes to counteract combined abiotic stresses. Candidate genes were identified that could explain the different physiological responses to stress observed in E42 compared with LA3120. Results here obtained have shown how new tomato genetic resources can be a valuable source of traits for adaptation to combined abiotic stresses and should be used in breeding programmes to improve stress tolerance in commercial varieties.


Asunto(s)
Solanum lycopersicum , Clorofila A , Genotipo , Respuesta al Choque Térmico/genética , Solanum lycopersicum/genética , Estrés Fisiológico/genética , Agua
4.
Plant Biol (Stuttg) ; 10(2): 194-201, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18304193

RESUMEN

We assessed the contribution of leaf movements to PSII photoprotection against high light and temperature in Robinia pseudoacacia. Gas exchange and chlorophyll a fluorescence measurements were performed during the day at 10:00, 12:00, 15:00 and 18:00 hours on leaves where paraheliotropic movements were restrained (restrained leaves, RL) and on control unrestrained leaves (UL). RL showed a strong decrease of net photosynthesis (A(n)), stomatal conductance (g(sH2O)), quantum yield of electron transport (PhiPSII), percentage of photosynthesis inhibited by O2 (IPO) and photochemical quenching (q(P)) in the course of the day, whereas, a significant increase in C(i)/C(a) and NPQ was observed. Contrary to RL, UL had higher photosynthetic performance that was maintained at elevated levels throughout the day. In the late afternoon, A(n), g(sH2O), PhiPSII and q(P) of RL showed a tendency to recovery, as compared to 15:00 hours, even if the values remained lower than those measured at 10:00 hours and in UL. In addition, contrary to UL, no recovery was found in F(v)/F(m) at the end of the study period in RL. Data presented suggest that in R. pseudoacacia, leaf movements, by reducing light interception, represent an efficient, fast and reversible strategy to overcome environmental stresses such as high light and temperature. Moreover, paraheliotropism was able to protect photosystems, avoiding photoinhibitory damage, leading to a carbon gain for the plant.


Asunto(s)
Fotosíntesis/fisiología , Robinia/metabolismo , Clorofila/metabolismo , Luz , Robinia/efectos de la radiación , Temperatura
5.
Plant Physiol ; 114(2): 737-746, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12223742

RESUMEN

Quinone oxidoreductase activities dependent on pyridine nucleotides are associated with the plasma membrane (PM) in zucchini (Cucurbita pepo L.) hypocotyls. In the presence of NADPH, lipophilic ubiquinone homologs with up to three isoprenoid units were reduced by intact PM vesicles with a Km of 2 to 7 [mu]M. Affinities for both NADPH and NADH were similar (Km of 62 and 51 [mu]M, respectively). Two NAD(P)H:quinone oxidoreductase forms were identified. The first, labeled as peak I in gel-filtration experiments, behaves as an intrinsic membrane complex of about 300 kD, it slightly prefers NADH over NADPH, it is markedly sensitive to the inhibitor diphenylene iodonium, and it is active with lipophilic quinones. The second form (peak II) is an NADPH-preferring oxidoreductase of about 90 kD, weakly bound to the PM. Peak II is diphenylene iodonium-insensitive and resembles, in many properties, the soluble NAD(P)H:quinone oxidoreductase that is also present in the same tissue. Following purification of peak I, however, the latter gave rise to a quinone oxidoreductase of the soluble type (peak II), based on substrate and inhibitor specificities and chromatographic and electrophoretic evidence. It is proposed that a redox protein of the same class as the soluble NAD(P)H:quinone oxidoreductase (F. Sparla, G. Tedeschi, and P. Trost [1996] Plant Physiol. 112:249-258) is a component of the diphenylene iodonium-sensitive PM complex capable of reducing lipophilic quinones.

6.
J Leukoc Biol ; 62(4): 469-79, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9335317

RESUMEN

About 10-15% of patients with immune thrombocytopenic purpura (ITP) cannot be controlled by corticosteroid therapy and splenectomy. For these patients treatment with high-dose IVIgG induces partial or complete responses. The clinical benefits of IVIgG could be due to blockade of Fc receptors for IgG (FcgammaR), because several model systems clearly show that functional FcgammaR are essential for establishment of ITP and related diseases. However, the specific contributions of the three individual classes of FcgammaR remain to be more completely defined. Recently monoclonal antibody (mAb) H22, which recognizes an epitope on FcgammaRI (CD64) outside the ligand binding domain, was humanized by grafting its complementarity determining regions onto human IgG1 constant domains. Because FcgammaRI has a high affinity for human IgG1 antibodies, we predicted mAb H22 would also bind to FcgammaRI through its Fc domain and block FcgammaRI-mediated phagocytosis. These studies demonstrate that mAb H22 blocked phagocytosis of opsonized red blood cells 1000 times more effectively than an irrelevant IgG. Moreover, cross-linking FcgammaRI with mAb H22 rapidly down-modulated FcgammaRI expression on monocytes without affecting other surface antigens. We conclude that because mAb H22 is a humanized mAb that blocks the FcgammaRI ligand binding domain and down-modulates FcgammaRI expression, it is a particularly good candidate for evaluating the role of FcgammaRI in patients with ITP.


Asunto(s)
Anticuerpos Monoclonales , Monocitos/inmunología , Fagocitosis , Receptores de IgG/fisiología , Animales , Antígenos CD/biosíntesis , Células Cultivadas , Epítopos/análisis , Eritrocitos/inmunología , Citometría de Flujo , Humanos , Regiones Constantes de Inmunoglobulina , Inmunoglobulina G , Cinética , Ratones , Modelos Inmunológicos , Receptores de IgG/biosíntesis , Receptores de IgG/inmunología
7.
J Leukoc Biol ; 55(2): 153-60, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8301211

RESUMEN

The goal of this investigation was to determine if human natural killer (NK) cells were susceptible to the cytolytic effects of the Actinobacillus actinomycetemcomitans leukotoxin (LTX). Following treatment with LTX (0-200 ng/ml), NK cell activation by interleukin-2 (IL-2) was evaluated. LTX inhibited the IL-2-induced expression of both CD69 and the IL-2 receptor. Furthermore, the up-regulation of CD56 was also impaired. To determine whether the observed functional deficits were the result of cell death, NK cell viability was evaluated by flow cytometry. Changes in forward and side light scatter patterns consistent with cell death were observed within 60 min. Direct analysis of cell viability by measuring propidium iodide exclusion, however, indicated little change in the viability of LTX-treated NK cells. Electron microscopic analysis of NK cells exposed to LTX revealed early nuclear alterations characterized by hyperchromaticity, nuclear fragmentation, and condensation of nucleoplasm. However, no change in membrane integrity was initially noted. Finally, LTX caused a rapid and sustained elevation in the intracellular levels of Ca2+. These morphological and biochemical changes are consistent with the notion of programmed cell death.


Asunto(s)
Toxinas Bacterianas/toxicidad , Exotoxinas/toxicidad , Células Asesinas Naturales/efectos de los fármacos , Aggregatibacter actinomycetemcomitans , Antígenos CD/biosíntesis , Antígenos de Diferenciación de Linfocitos T/biosíntesis , Supervivencia Celular/efectos de los fármacos , Citometría de Flujo/métodos , Interleucina-2/farmacología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/ultraestructura , Cinética , Lectinas Tipo C , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Receptores de Interleucina-2/biosíntesis
8.
Exp Hematol ; 20(7): 850-4, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1378407

RESUMEN

The in vitro growth of early (megakaryocyte burst-forming units, BFU-meg) and late (megakaryocyte colony-forming units, CFU-meg) megakaryocyte (meg) progenitors has been evaluated in normal adult human peripheral blood (PB). All the experiments were carried out using CD34+ cells, which were assayed in a serum-free fibrinclot assay. PB BFU-meg were morphologically characterized as plurifocal aggregates containing greater than 50 cells/colony, distinct from unifocal CFU-meg, in a limiting dilution assay. At variance with PB CFU-meg, PB BFU-meg were unaffected by the complement-mediated cytotoxicity with anti-HLA-DR. The optimal source of colony-stimulating activity for PB BFU-meg growth was recombinant human interleukin 3 (rhIL-3; 100 U/ml), which supported a significantly higher number of BFU-meg in comparison with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 200 U/ml, p = 0.043). Combinations of rhIL-3 (100 U/ml) plus rhGM-CSF (200 U/ml), rhIL-3 plus recombinant human interleukin 6 (rhIL-6; 100 U plus 100 U/ml) or rhIL-3 plus rhGM-CSF plus rhIL-6 (100 U plus 200 U/ml plus 100 U/ml) failed to further increase the number of PB BFU-meg with respect to rhIL-3 (100 U/ml) alone. Both PB BFU-meg and CFU-meg were markedly inhibited, in a dose-dependent fashion, by increasing doses of human purified transforming growth factor-beta 1 (TGF-beta 1) (from 0.001 to 10 ng/ml). Finally, the CFU-meg/BFU-meg ratio in PB (0.52) was significantly different from that of normal bone marrow (2.3), clearly indicating that adult human peripheral blood predominantly carries primitive megakaryocytic progenitors.


Asunto(s)
Células Precursoras Eritroides/citología , Megacariocitos/citología , Adulto , Antígenos CD/análisis , Antígenos CD34 , Médula Ósea/inmunología , Células de la Médula Ósea , Células Clonales , Ensayo de Unidades Formadoras de Colonias , Medio de Cultivo Libre de Suero , Citotoxicidad Inmunológica , Células Precursoras Eritroides/efectos de los fármacos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Humanos , Interleucina-3/farmacología , Interleucina-6/farmacología , Megacariocitos/efectos de los fármacos , Fenotipo , Proteínas Recombinantes/farmacología , Células Madre/inmunología
9.
Exp Hematol ; 17(7): 755-9, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2753083

RESUMEN

The antiproliferative effect of saporin 6 (SO6), a ribosome-inactivating protein (RIP) purified from the seeds of Saponaria officinalis has been tested on three leukemic cell lines (K562, U937, and HL60), human normal bone marrow, and peripheral blood hemopoietic progenitor cells from normal subjects. In leukemic cell lines, SO6 appeared much more effective against erythrocytic than against monocytic and promyelocytic leukemic cells, as shown by protein synthesis assays carried out after up to 72 h of culture. Among the normal hemopoietic progenitor cells, erythroid burst-forming units were the most affected, with results similar to those observed in the erythroid leukemic cell line, both in treated and in pretreated cultures, with strong damage after 24 h of exposure to SO6. On the other hand, granulocyte-macrophage colony-forming units (CFU-GM) from bone marrow were significantly more affected than the myeloid leukemic cell lines after permanent treatment with the inhibitor, the damage being significantly lower after an exposure of 24 h. CFU-GM from peripheral blood and megakaryocyte CFU showed an intermediate sensitivity after 24 h of exposure to SO6, similar to that of the other normal precursors after permanent treatment with the drug.


Asunto(s)
Inhibidores de Crecimiento , Células Madre Hematopoyéticas/efectos de los fármacos , Inmunotoxinas , N-Glicosil Hidrolasas , Proteínas de Plantas/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Células de la Médula Ósea , División Celular/efectos de los fármacos , Ensayo de Unidades Formadoras de Colonias , Humanos , Técnicas In Vitro , Biosíntesis de Proteínas , Proteínas Inactivadoras de Ribosomas Tipo 1 , Ribosomas/efectos de los fármacos , Saporinas
10.
Exp Hematol ; 27(1): 9-18, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9923439

RESUMEN

The hematopoietic defect of Diamond-Blackfan anemia (DBA) results in selective failure of erythropoiesis. Thus far, it is not known whether this defect originates from an intrinsic impediment of hematopoietic progenitors to move forward along the erythroid pathway or to the impaired capacity of the bone marrow (BM) microenvironment to support proliferation and differentiation of hematopoietic cells. Reduced longevity of long-term bone marrow cultures, the most physiologic in vitro system to study the interactions of hematopoietic progenitors and hematopoietic microenvironment, is consistent with a defect of an early hematopoietic progenitor in DBA. However, stromal adherent layers from DBA patients generated in a long-term culture system, the in vitro counterpart of BM microenvironment, did not show evidence of any morphologic, phenotypic, or functional abnormality. Our major finding was an impaired capacity of enriched CD34+ BM cell fraction from DBA patients, cultured in the presence of normal BM stromal cells, to proliferate and differentiate along the erythroid pathway. A similar impairment was observed in some DBA patients along the granulomacrophage pathway. Our result points to an intrinsic defect of a hematopoietic progenitor with bilineage potential that is earlier than previously suspected as a relevant pathogenetic mechanism of the disease. The finding of impaired granulopoiesis in some DBA patients underlines the heterogeneity of this rare disorder.


Asunto(s)
Células de la Médula Ósea/patología , Anemia de Fanconi/patología , Granulocitos/patología , Células Madre Hematopoyéticas/patología , Macrófagos/patología , Adolescente , Adulto , Antígenos CD34/análisis , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/fisiología , Diferenciación Celular , División Celular , Supervivencia Celular , Células Cultivadas , Niño , Preescolar , Medios de Cultivo Condicionados/farmacología , Citocinas/genética , Células Precursoras Eritroides/efectos de los fármacos , Células Precursoras Eritroides/metabolismo , Células Precursoras Eritroides/patología , Femenino , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Inmunofenotipificación , Lactante , Masculino , ARN Mensajero/biosíntesis , Células del Estroma/fisiología , Factores de Tiempo
11.
FEBS Lett ; 253(1-2): 79-82, 1989 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-2759246

RESUMEN

A new Cl- -activated aminopeptidase was purified from the cytosol of human erythrocytes as a single chain protein of an approx. Mr of 70,000 and pI of 5.1. The enzyme hydrolysed 2-naphthylamides of aliphatic, aromatic and basic L-amino acids, with a preference for the alanyl residue. It also hydrolysed di-, tri-, and some hydrophobic tetrapeptides. The inhibitors were bestatin, amastatin, Co2+, Zn2+, Mn2+, 4-hydroxymercuribenzoate and 1,10-phenanthroline. The activity of the enzyme, inhibited by 4-hydroxymercuribenzoate, was partially restored by the addition of sulfhydryl compounds. The presence of 0.2 M Cl- (Br-,F-) caused a several-fold increase in the isolated aminopeptidase activity.


Asunto(s)
Aminopeptidasas/sangre , Eritrocitos/enzimología , Cloruros/farmacología , Citosol/enzimología , Activación Enzimática , Humanos , Especificidad por Sustrato
12.
Free Radic Biol Med ; 20(3): 483-8, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8720922

RESUMEN

GSH and its related enzymes are one of the protective mechanisms vs. the oxidative damage, both in the circulation and in various tissues, including gastric mucosa. Patients with liver cirrhosis frequently suffer from a gastropathy caused by portal hypertension and they present low circulating levels of GSH. Aging processes cause an increase of gastric damage, of lipoperoxidative phenomenons, and a decrease of GSH in animals. The aim of this study was the evaluation, in humans, of the effect of both these factors, age and liver cirrhosis, on the global pool of GSH and on the antioxidant capability of the cells of gastric mucosa. Therefore, we evaluated the effect of liver cirrhosis and age on the circulating levels of GSH, both in the plasma and in the erythrocytes, and the GSH concentration and the activity of the total GSH-transferase (GSH-T) in gastric mucosa of healthy subjects and in patients affected by liver cirrhosis. Age, but not liver cirrhosis, induced a significant decrease of GSH and GSH-T activity in gastric mucosa; on the contrary, the plasma levels of GSH decreased in cirrhotics but not in elderly healthy subjects. In the erythrocytes, GSH was affected by both these factors (age and liver cirrhosis). These findings indicate that both in patients with liver disease and in elderly healthy subjects the GSH-related cellular defensive mechanisms are depressed and therefore susceptibility to oxidative damage may increase.


Asunto(s)
Envejecimiento/metabolismo , Eritrocitos/metabolismo , Mucosa Gástrica/química , Glutatión/metabolismo , Cirrosis Hepática/metabolismo , Adulto , Anciano , Análisis de Varianza , Femenino , Mucosa Gástrica/crecimiento & desarrollo , Mucosa Gástrica/patología , Glutatión/sangre , Glutatión Transferasa/metabolismo , Humanos , Cirrosis Hepática/sangre , Masculino , Persona de Mediana Edad , Valores de Referencia , Análisis de Regresión
13.
Eur J Cancer ; 34(3): 399-405, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9640230

RESUMEN

Exopeptidases, in contrast to endopeptidases (proteinases) have been much less studied in relation to cancer. The aim of this study was to investigate one such enzyme, dipeptidyl peptidase III (DPP III), in gynaecological tissues, by measuring both the enzyme activity and enzyme content. DPP III activity was assessed in normal (n = 65), benign (n = 9) and malignant (n = 51) gynaecological tissues. A statistically significant higher DPP III activity was observed in endometrial (n = 40, P = 4.6 x 10(-7)) and ovarian (n = 11, P = 8.1 x 10(-4)) malignant tumours, whereas no significant difference was detected for leiomyomas (n = 8), if compared to the activity in normal tissue. A matched pair analysis of normal and cancerous endometrial tissue confirmed the significance of the DPP III activity increase in the transformed tissue (n = 7, P = 0.022). Western blot analysis revealed a significantly (P = 0.014) increased level of DPP III in endometrial cancer. Further, regression analysis showed a positive correlation between the activity and the content of DPP III in normal tissue (r = 0.637, P = 0.047) and in endometrial cancer (r = 0.574, P < 0.007). The increase of the DPP III activity was observed in the endometrial carcinomas of various histological types, grade or the depth of myometrial invasion. The easy-to-perform determination of this exopeptidase activity may serve as a potential indicator of endometrial and ovarian malignancies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Neoplasias Ováricas/enzimología , Neoplasias Uterinas/enzimología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Electroforesis en Gel de Poliacrilamida , Neoplasias Endometriales/enzimología , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Ováricas/patología , Neoplasias Uterinas/patología
14.
Am J Med ; 59(5): 630-41, 1975 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1200035

RESUMEN

Among eight subjects suspected of excessive occupational exposure to lead, detailed examination of renal function identified abnormalities in four. Glomerular filtration rate was less than 87 ml/mim/1.73 m2 in one subject with asymptomatic renal failure, and in three subjects with preclinical renal dysfunction. In the subject with asymptomatic renal failure, chelation therapy increased the glomerular filtration rate, p-aminohippurate (PAH) extraction, the maximal PAH secretion rate (TmPAH) and improved proximal tubule ultrastructure, despite decreased renal plasma flow. This improvement in PAH transport was associated with correction of a proximal tubule defect in tritiated PAH uptake detected by section freeze-dry autoradiography of renal biopsy specimens. In three subjects, the etiologic diagnosis of lead-induced nephropathy was established by exclusion, but tubular dysfunction did not obviously exceed the reduction in blomerular filtration. Proximal tubule abnormalities were seen in each of the three patients who underwent biopsy. These studies suggest that lead nephropathy may be an important occupational hazard in the United States lead industry.


Asunto(s)
Enfermedades Renales/fisiopatología , Riñón/fisiopatología , Intoxicación por Plomo/fisiopatología , Enfermedades Profesionales/fisiopatología , Ácidos Aminohipúricos/metabolismo , Autorradiografía , Tasa de Filtración Glomerular , Humanos , Riñón/patología , Enfermedades Renales/metabolismo , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/ultraestructura , Intoxicación por Plomo/metabolismo , Intoxicación por Plomo/patología , Microscopía Electrónica , Enfermedades Profesionales/metabolismo , Enfermedades Profesionales/patología
15.
Mol Cell Endocrinol ; 47(3): 235-41, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3093296

RESUMEN

A specific nuclear protein (SNP) appears in the oviduct of the lizard, Podarcis s. sicula Raf., during the recovery phase of the breeding cycle. The protein has a low molecular weight (9.9 kDa), a high electrophoretic mobility and a peculiar amino acid composition. It seems to be regulated by estradiol which, in this species, is involved in oviduct stimulation. Nuclear poly(ADPribose)transferase activity increases in the oviduct as the organ grows, and it peaks upon morphological maturation. Thereafter, as the oviduct becomes secretory, the enzyme returns to basal level. A transient increase of poly(ADPribose)transferase precedes the appearance of SNP, which suggests that the two phenomena are related.


Asunto(s)
Lagartos/fisiología , Nucleoproteínas/metabolismo , Oviductos/fisiología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Animales , Estradiol/fisiología , Estro , Femenino , Peso Molecular , Estaciones del Año
16.
Anticancer Res ; 8(6): 1303-6, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3218962

RESUMEN

The effect of different Esorubicin concentrations (10(-7) M to 10(-10) M) has been tested on the in vitro growth of human normal hemopoietic progenitor cells and of three leukemic cell lines (K562, U 937, HL60). The highest drug concentration completely abolished both normal and leukemic proliferation. Lower doses of Esorubicin failed to induce any morphological or phenotypic differentiation of leukemic cell lines. A 24h pretreatment of the cells with 10(-9) M Esorubicin enhanced the in vitro proliferation of normal early myeloid progenitor cells, whereas it did not affect leukemic, myelomonocytic cell proliferation.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Doxorrubicina/análogos & derivados , Células Madre Hematopoyéticas/citología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Doxorrubicina/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Leucemia , Valores de Referencia
17.
Folia Histochem Cytobiol ; 24(2): 139-48, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3095153

RESUMEN

In human polymorphonuclear leukocytes a methionine, leucine, arginine, phenylalanine and alanine aminopeptidase activities were detected, both in cytosol and secondary granules. All activities were EDTA sensitive and their pH optima were in the range of pH 6.5 to 8.6. In the cytosol two enzymes could be distinguished, broad substrate specificity aminopeptidase of pH 4.7-4.9 and a chloride dependent arginine aminopeptidase of pI 5.3-5.5. The granules contain aminopeptidase of pI 4.0-4.6 and of pI 9.8-10.2, different from those in the cytosol. Among them broad specificity aminopeptidases and possibly specific methionine and leucine aminopeptidases could be discerned.


Asunto(s)
Aminopeptidasas/sangre , Neutrófilos/enzimología , Alanina/metabolismo , Aminopeptidasas/antagonistas & inhibidores , Arginina/metabolismo , Gránulos Citoplasmáticos/enzimología , Citosol/enzimología , Ácido Edético/farmacología , Humanos , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Leucina/metabolismo , Metionina/metabolismo , Microscopía Electrónica , Neutrófilos/ultraestructura , Fenilalanina/metabolismo , Especificidad por Sustrato
18.
Arch Environ Health ; 34(3): 168-73, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-453925

RESUMEN

Groups of ten male Wistar rats were fed 100 mg lead/kg body wt . day, or 100 mg lead plus 250 mg Mg . kg body wt . day mixed in the powdered diet as chlorides. Blood and urine were monitored for lead-related enzymes and lead concentrations. Compared to the lead-treated, blood lead and urinary aminolevulinic acid were much lower and blood aminolevulinic acid dehydratase and urinary lead were higher at 30, 45, and 62 days in the lead-magnesium-treated animals. At 45 and 62 days, blood lead was higher in the lead-magnesium group even though the urinary excretion of lead was significantly higher (P less than .01). At 62 days, the lead feeding was discontinued to both groups, but magnesium administration was continued. Both groups of rats were then monitored for urinary excretion of lead and this was significantly higher (P less than .01) in the rats fed magnesium suggesting that magnesium intake helped mobilize lead from bone, thus increasing the blood lead level and subsequent urine excretion. Enzyme levels approached normal values at 106 days only in the lead-magnesium group, thereby indicating low levels of lead toxicity. Lead levels of bones in rats of the lead-magnesium group, when sacrificed at 106 days, were significantly lower (P less than .01) than among those given lead alone, another indication that magnesium helped mobilize lead from bone. The results, therefore, clearly show that feeding magnesium leads to lower retention and increased excretion of lead under the experimental conditions outlined.


Asunto(s)
Plomo/toxicidad , Magnesio/farmacología , Ácido Aminolevulínico/análisis , Animales , Huesos/análisis , Química Encefálica , Dieta , Riñón/análisis , Plomo/análisis , Hígado/análisis , Pulmón/análisis , Miocardio/análisis , Porfobilinógeno Sintasa/análisis , Ratas , Bazo/análisis
19.
Minerva Chir ; 49(3): 163-5, 1994 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-8028724

RESUMEN

The authors explain the clinical and anatomical features of retroperitoneal abscesses, which occur less commonly than peritoneal infections. Retroperitoneal abscesses arise chiefly from injuries in adjacent structures, but they may be primary when caused by hematogenous bacterial spread. The pyogenic bacteria have replaced Mycobacterium tuberculosis as the major causative organism. Retroperitoneal abscesses may be symptomless, but fever and abdominal pain are prominent features. The differential diagnosis includes retroperitoneal tumors and hematomas. These lesions are best delimited by CT scanning which localizes them accurately. The treatment consists in a prompt and adequate drainage and systemic antibiotics therapy. Drainage by catheter, however, has a lower success rate than the surgical approach. The surgical mortality rate is about 25%.


Asunto(s)
Absceso/diagnóstico , Absceso/terapia , Espacio Retroperitoneal , Absceso/cirugía , Antibacterianos/uso terapéutico , Diagnóstico Diferencial , Drenaje , Humanos , Nutrición Parenteral Total , Tomografía Computarizada por Rayos X
20.
Minerva Chir ; 49(10): 977-9, 1994 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-7808674

RESUMEN

Vesicovaginal fistulas are commonly seen as a complication of abdominal (or vaginal) Hysterectomy. The signs and symptoms of a vesicovaginal fistula depend upon its size and location. Identification of a vesicovaginal fistula includes an intravenous urogram; cystoscopy may be performed in order to evaluate the possibility of immediate or delayed repair. Case report. Principles of surgical repair. The principles of surgical closure are similar: 1) total separation of the tissues comprising the wall of the vagina and the wall of the bladder; 2) sharp excision of the fistulous tract between to two structures; 3) closure of the defects with non-overlapping suture lines; 4) where possible, interposition of alternative tissue between the two suture lines. The intervention proposed by Legueu allows an abdominal transperitoneal approach to the fistula and is comprehensive of these principles. With such a procedure we have treated successfully two cases which required surgical closure. CONCLUSIONS. In patients who develop vesicovaginal fistulas as a complication of abdominal hysterectomy, we have applied the intervention proposed be Legueu, which allows closure of the fistula via a transperitoneal route. Preliminar diagnostic evaluation and following of the foundamental principles of correct surgical closure are indispensable to accomplish a successful intervention.


Asunto(s)
Histerectomía/efectos adversos , Vejiga Urinaria/cirugía , Vagina/cirugía , Fístula Vesicovaginal/cirugía , Adulto , Femenino , Humanos , Persona de Mediana Edad , Reoperación , Procedimientos Quirúrgicos Operativos/métodos , Fístula Vesicovaginal/etiología
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