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1.
Occup Med (Lond) ; 73(8): 512-517, 2023 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-38029440

RESUMEN

BACKGROUND: In 2017, 69 108 work-related traffic injuries with medical leave were documented, constituting 12% of all occupational injuries (OI) in Spain. AIMS: The aim of this study was to describe OI within a Spanish bank company during 2017. METHODS: A cross-sectional analysis was conducted using the company's mandatory OI records, presenting data in both absolute (n) and relative (%) frequencies. The chi-square test was employed for comparisons. RESULTS: Among the company's 10 399 employees, 176 OI cases were recorded. Most were minor musculoskeletal incidents, with one severe myocardial infarction and one mild anxiety episode. Lower limb injuries were the most prevalent. Injuries of the trunk (P < 0.001), neck (P < 0.05), and upper limbs (P < 0.001) were linked to workplace factors. Approximately 62% of OI occurred outside the workplace and resulted in more extended medical leave (P < 0.01). Traffic-related injuries accounted for 39% of OI cases and caused 49% of days lost due to OI (P < 0.001).Female gender (P < 0.001) and age over 40 years (P < 0.05) were significantly associated with OI. CONCLUSIONS: In our study, musculoskeletal injuries were the most common, with a single cardiovascular event being the most severe. OI occurring outside the workplace was more frequent and led to longer medical leaves. Notably, traffic-related injuries were especially significant, exceeding official statistics 4-fold.


Asunto(s)
Infarto del Miocardio , Traumatismos Ocupacionales , Humanos , Femenino , Adulto , Traumatismos Ocupacionales/epidemiología , Traumatismos Ocupacionales/etiología , Estudios Transversales , Lugar de Trabajo , Infarto del Miocardio/complicaciones , España/epidemiología
2.
Sci Total Environ ; 859(Pt 1): 160272, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36403836

RESUMEN

In hydrogeological research, the systematic and periodic measurement of the piezometric level is fundamental to assess aquifer storage, identify recharge and discharge areas, define flow directions and to infer the balance between inputs and withdrawals. Furthermore, knowledge of this variable and its fluctuations is essential for the efficient management and protection of groundwater resources. In this work, a novel methodology is proposed for the remote acquisition of piezometric information from traditional large-diameter wells, using drone-borne LiDAR observations. The workflow developed consists of different stages, from flight planning and parameter setting, to point cloud generation, data processing and validation and its statistical treatment to extract piezometric information. This methodology has been applied in a small coastal aquifer with numerous wells that have served as monitoring points. The UAV-LiDAR has enabled the straightforward obtention of measurements of the piezometric level with very high vertical accuracies (RMSE of 5 cm) with minimum and maximum residuals of -8.7 and 7.9 cm respectively. Likewise, the method has shown vertical accuracies 3 times better than those inferred from the official DTM of best resolution available in Spain, which is usually used in hydrogeological works. Since the technique provides absolute values of the piezometric level, it eliminates the need for laborious levelling work prior to hydrogeological campaigns. This method has proved to be an effective alternative/complementary technique to traditional measurements of the piezometric level, allowing to monitor extensive or inaccessible areas over short periods of time and to potentially reduce gaps in hydrogeological databases.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Monitoreo del Ambiente/métodos , Pozos de Agua , España
3.
Semergen ; 46(4): 225-233, 2020.
Artículo en Español | MEDLINE | ID: mdl-32291191

RESUMEN

OBJECTIVE: This purpose of this work is to determine the care preferences and the required use of medical care by migraine patients in the different countries of Europe, and the observed differences depending on their social and demographic conditions. MATERIAL AND METHODS: Cross-sectional observational study by anonymous web survey of 3,342 patients from Spain, Italy, France, Portugal, Ireland, United Kingdom, Germany, and a mixed group of countries not included in the initial design. VARIABLES: age, gender, country, type of location, level of studies and rural or urban area. The demand for care is collected by neurologist, primary care doctors/family/general practitioners, by occupational health doctors, nurses, by other doctors/other specialists, non-medical control/self-control. RESULTS: The patients more seen by a neurologist were about 21-60years old and with a high cultural level. Primary care/family doctor care is higher in urban areas. Occupational medicine, nursing, and other specialties predominate in large cities. Self-control is greater in patients aged 21-40years and in women. Spain and Germany are the countries with the greatest demand for care in Neurology and Primary Care. CONCLUSIONS: The medical demand for migraine care in Europe shows irregular results according to countries, with it being a priority in neurology and with less participation of Primary Care physicians, work doctors, nurses, or other specialties. Differences are observed by age, gender, and cultural level both in the demand for care and in the choice of specialist. It is important to take into account the percentage of patients who have no medical control.


Asunto(s)
Trastornos Migrañosos , Estudios Transversales , Europa (Continente) , Femenino , Francia , Humanos , Irlanda , Italia , Portugal , España , Reino Unido
4.
Osteoarthr Cartil Open ; 2(3): 100068, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36474684

RESUMEN

Objective: Fibroblast growth factor 18 (FGF18) is involved in chondrogenesis and articular cartilage repair. We investigated tissue distribution and pharmacokinetics of radioactive [3H]sprifermin, a recombinant human FGF18, in rats after a single intravenous (i.v.) or intra-articular (i.a.) injection. Design: In two studies (48-96-h [n = 23] and 28-day [n = 12]), 35 male albino (Sprague Dawley) rats received single i.v. or i.a. dose [3H]sprifermin (0.24 mg/kg). Radioactivity was measured in blood, serum, and (in animals receiving i.a. administration) in the knee joint by liquid scintillation counting. Radioactivity in organs, tissues, and distribution in the whole body were measured with whole-body autoradiography. Results: After i.v. injection, radioactivity peaked in serum and whole blood after 4 and 24 h, respectively, with greater total radioactivity in serum. After i.a. injection, radioactivity peaked in serum and whole blood after 24 and 48 h, respectively; intact [3H]sprifermin was not detected in vena caval serum and systemic exposure was low, approximately 20% of that with i.v. injection. Following i.v. injection, radioactivity was mainly found in the liver, adrenal glands, kidney, and spleen; following i.a. injection, radioactivity was preferentially concentrated in articular cartilage after initial distribution in the joint capsule, and still evident in the joint after 28 days. Conclusions: After i.a. injection of [3H]sprifermin in rats, radioactivity was concentrated in the knee joint, particularly articular cartilage, with low levels in other investigated tissues. Systemic exposure to sprifermin was greater with i.v. than i.a. injection. Subsequent clinical investigation in patients with osteoarthritis has reported consistent results.

5.
J Contam Hydrol ; 222: 65-75, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30850109

RESUMEN

The Río Tinto mining area provides ideal conditions for studying the role of colloidal particles in concentrating. All the elements are present in higher concentrations respect to their content in common natural waters. 234U/238U activity ratio ranges between 2.286 ±â€¯0.149 and 2.531 ±â€¯0.151. Concentration of Fe and Al are in the order of 104-103 mg/L; Co, Zn and Cu values are three times lower than Fe and Al, but still much greater than in natural waters; U reaches values up to 40.73 µg/L. To evaluate the partitioning of these elements into the colloidal fraction, ultrafiltration (UF) experiments were made. A permeation model describing the relationship between concentration of the elements or isotopes in the permeate solution and the concentration factor (CF) was calculated. Experiments were carried out using CF from 1.5 to 25.0. The behaviour of investigated heavy metals and U can be predicted by a permeation model that provides similar permeation coefficient (Pc) for all of them (Pc = 0.95-0.97 for 50 kDa, Pc = 0.86-0.88 for 10 kDa, and Pc = 0.80-0.86 for 3 kDa). Retention for all the investigated elements occurs, resulting in up to 23% of the element associated to the 3 kDa colloidal fraction. The increase in U and heavy metals concentrations in the retentate fraction with the increasing CF is due to the retention of the colloidal fraction. The colloidal abundance of related metals increased with decreasing membrane MWCO even though the difference is small between 3 and 10 kDa fraction for some metals Characterization of colloidal material is needed to better understand the state of play in this context.


Asunto(s)
Metales Pesados , Minería , España
6.
BMC Pregnancy Childbirth ; 19(1): 14, 2019 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-30621614

RESUMEN

BACKGROUND: Among the various methods available, the administration of prostaglandins is the most effective for inducing labour in women with an unfavourable cervix. Recent studies have compared treatment with various titrated doses of oral misoprostol with vaginal misoprostol or dinoprostone, indicating that the use of an escalating dose of an oral misoprostol solution is associated with a lower rate of caesarean sections and a better safety profile. The objective of this study is to assess which of these three therapeutic options (oral or vaginal misoprostol or vaginal dinoprostone) achieves the highest rate of vaginal delivery within the first 24 h of drug administration. METHODS: An open-label randomised controlled trial will be conducted in Araba University Hospital (Spain). Women at ≥41 weeks of pregnancy requiring elective induction of labour who meet the selection criteria will be randomly allocated to one of three groups: 1) vaginal dinoprostone (delivered via a controlled-release vaginal insert containing 10 mg of dinoprostone, for up to 24 h); 2) vaginal misoprostol (25 µg of vaginal misoprostol every 4 h up to a maximum of 24 h); and 3) oral misoprostol (titrated doses of 20 to 60 µg of misoprostol following a 3 h on + 1 h off regimen up to a maximum of 24 h). Both intention-to-treat analysis and per-protocol analysis will be performed. DISCUSSION: The proposed study seeks to gather evidence on which of these three therapeutic options achieves the highest rate of vaginal delivery with the best safety profile, to enable obstetricians to use the most effective and safe option for their patients. TRIAL REGISTRATION: NCT02902653 Available at: https://clinicaltrials.gov/show/NCT02902653 (7th September 2016).


Asunto(s)
Maduración Cervical/efectos de los fármacos , Dinoprostona/administración & dosificación , Trabajo de Parto Inducido/métodos , Misoprostol/administración & dosificación , Oxitócicos/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Administración Intravaginal , Administración Oral , Adolescente , Adulto , Quimioterapia Combinada , Femenino , Humanos , Embarazo , Resultado del Tratamiento , Adulto Joven
7.
J Environ Radioact ; 130: 68-71, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24463722

RESUMEN

The activity ratios of (234)U/(238)U were used to investigate processes of subterranean groundwater discharge into coastal marine waters in a study location at Bay of Cádiz (southwest Spain). Marine waters in the bay and surrounding open ocean exhibited U concentrations of 3.4 ± 0.1 µg/L and activity ratios of 1.15 ± 0.01, in agreement with the expected composition of seawater ((234)U/(238)U activity ratio = 1.148 ± 0.002). Three water samples obtained from the discharge zone of the Guadalete River exhibited activity ratios of 1.17-1.22 along with slightly lower U concentrations compared to seawater, which is likely due to mixing between seawater and a groundwater end-member. One possible source of groundwater was characterized by sampling and analyzing a well water sample collected in the neighboring village of El Puerto de Santa María; this water sample exhibited an activity ratio of 1.34 ± 0.03 and a U concentration of 1.22 µg/L. Water from the Guadelete River estuarine zone can be explained to result from a two-component mixture of seawater and groundwater from the El Puerto de Santa María well; however, if there are several groundwater reservoirs with different U activity ratios that discharge to the coastal water, then, it may be difficult and more studies are being conducted to address this issue.


Asunto(s)
Agua Subterránea/análisis , Monitoreo de Radiación , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Espectrometría de Masas , Ríos/química , Agua de Mar/análisis , España
8.
J Environ Radioact ; 138: 384-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24308958

RESUMEN

Under acid mine drainage (AMD) conditions, the solubilities and mobilities of many elements are vastly different from conditions prevailing in most natural waters. Studies are underway in the Río Tinto area (Iberian Pyrite Belt), in order to understand the behavior and mobility of long-lived U-series radionuclides under AMD conditions. A set of leaching experiments utilizing typical country rocks from the Tinto River basin, waste rock pile composite materials, iron-rich riverbed sediments and gossan (weathered naturally rock) were performed towards this purpose. Initial leaching experiments using distilled water kept in contact with solid material for 300, 100, 50 and 1 h resulted in very low concentrations of U with (234)U/(238)U activity ratios close to equilibrium and activity concentrations of (210)Po < 0.03 mBq/g. Leaching experiments performed with sulfuric acid media (0.1 and 0.01 M), and contact times between the solid and solution for 24 h were conducted to quantify the amount of U-isotopes and (210)Po leached, and the radioactive disequilibria generated between the radionuclides in the leachate. These experiments show that Po mobility in acidic conditions (pH around 1-2) is very low, with (210)Po activity in the leachate to be 6% in average for the solid sample. By contrast, mobility of U-isotopes is higher than that of Po, around 1.2%.


Asunto(s)
Polonio/análisis , Monitoreo de Radiación , Ríos/química , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Concentración de Iones de Hidrógeno , Minería , España
10.
Radiat Prot Dosimetry ; 150(1): 60-70, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21896553

RESUMEN

In order to investigate the radiological hazard of naturally occurring radioactive material (NORM) and man-made (137)Cs radionuclide in the Bay of Cádiz, 149 samples of sediments have been analysed. Activity concentration in all the samples was determined using a HPGe detection system. Activity concentrations values of (226)Ra, (232)Th, (40)K and (137)Cs in the samples were 12.6±2.6 (2.5-40.6), 18.5±4.0 (2.8-73.4), 451±45 (105-1342) and 3.2±1.3 (0.2-16.0) Bq kg(-1), respectively. Outdoor external dose rate due to natural and man-made radionuclides was calculated to be 35.79±1.69 (4.71-119.16) nGy h(-1) and annual effective dose was estimated to be 43.89±2.27 (5.78-146.14) µSv y(-1). Results showed low levels of radioactivity due to NORM and man-made (137)Cs radionuclide in marine sediments recovered from the Bay of Cádiz (Spain), discarding any significant radiological risks related to human activities of the area. Furthermore, the obtained data set could be used as background levels for future research.


Asunto(s)
Radiación de Fondo , Radioisótopos de Cesio/análisis , Sedimentos Geológicos/análisis , Materiales Manufacturados/análisis , Monitoreo de Radiación/estadística & datos numéricos , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Bahías/química , Ciudades/estadística & datos numéricos , Sedimentos Geológicos/química , Dosis de Radiación , España
11.
Arq. bras. med. vet. zootec ; 62(3): 645-653, June 2010. graf, tab
Artículo en Portugués | LILACS | ID: lil-554935

RESUMEN

Neste estudo foram utilizados os tratamentos: coastcross + amendoim forrageiro + 200kg/ha de N; coastcross + amendoim forrageiro + 100kg/ha de N; coastcross + 200kg/ha de N e coastcross + amendoim forrageiro (parcelas) no inverno, primavera, verão e outono (sub parcelas), delineados em blocos ao acaso. Novilhas foram manejadas sob lotação contínua e taxa de lotação variável em pastagem mantida a 17cm de altura. Amostras foram coletadas a cada 28 dias para determinar o valor nutritivo da forragem. Foram avaliados: ganho médio diário (GMD), ganho de peso vivo (GPV), taxa de lotação (TL) e número de animais dia (NAD). Quanto ao valor nutritivo da forragem, os piores resultados ocorreram nas pastagens sem adubação, 16,9 por cento e 6,0 por cento de PB de folha e colmo, respectivamente, e 70,1 por cento de FDN de folha. Na primavera e no verão, o GMD foi mais alto, 0,518 e 0,515kg/animal do que no inverno e outono, 0,396 e 0,293kg/animal, respectivamente. A TL foi superior nas pastagens que receberam a maior dose de nitrogênio, 5,38UA/ha em média, e no verão, 6,81UA/ha. O GPV foi mais elevado nas áreas com adubação, 1341kg de PV/ha, em relação aos pastos não adubados, 735kg/ha.


In this study, the ollowing treatments were used: coastcross + forage peanut + 200kg/ha of N; coastcross + forage peanut + 100kg/ha of N; coastcross + 200kg/ha of N and coastcross + forage peanut (plots) in the winter, spring, summer, and autumn (subplots), designed in randomized blocks. Heifers were managed under continuous stocking and variable stocking rate on pasture maintained at 17cm height. Samples were collected every 28 days determining the nutritional value of forage. Average daily gain (ADG), weight gain (WG), stocking rate (SR), and number of animals/day (NAD) were evaluated. As for forage nutritional value, the worst results were found in pasture without fertilization, 16.9 percent and 6.0 percent CP of leaf and stem, respectively, and 70.1 percent NDF in leaves. In the spring and summer, animals had a higher ADG, 0.518 and 0.515kg/animal, than 0.396 and 0.293kg/animal in the winter and autumn, respectively. SR was higher in pastures that received higher nitrogen doses, 5.38AU/ha in average; and in the summer, 6.81AU/ha. LWG was higher in fertilized areas, 1,341kg LW/ha, than in not fertilized pastures, 735kg/ha.


Asunto(s)
Animales , Bovinos , Alimentación Animal , Arachis , Cynodon dactylon , Ciencias de la Nutrición Animal , Bovinos , Estiércol
12.
Appl Radiat Isot ; 68(9): 1602-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20219381

RESUMEN

A new method using the inventory determined for the activity of the radionuclide (137)Cs, coming from global radioactive fallout has been utilised to calculate the sedimentation rates. The method has been applied in a wide intertidal region in the Bay of Cádiz Natural Park (SW Spain). The sedimentation rates estimated by the (137)Cs inventory method ranged from 0.26 cm/year to 1.72 cm/year. The average value of the sedimentation rate obtained is 0.59 cm/year, and this rate has been compared with those resulting from the application of the (210)Pb dating technique. A good agreement between the two procedures has been found. From the study carried out, it has been possible for the first time, to draw a map of sedimentation rates for this zone where numerous physico-chemical, oceanographic and ecological studies converge, since it is situated in a region of great environmental interest. This area, which is representative of common environmental coastal scenarios, is particularly sensitive to perturbations related to climate change, and the results of the study will allow to make short and medium term evaluations of this change.


Asunto(s)
Algoritmos , Radioisótopos de Cesio/análisis , Sedimentos Geológicos/análisis , Sedimentos Geológicos/química , Monitoreo de Radiación/métodos , Contaminantes Radiactivos del Suelo/análisis , Dosis de Radiación , España
13.
Arq. bras. med. vet. zootec ; 61(4): 918-926, ago. 2009. ilus, tab
Artículo en Portugués | LILACS | ID: lil-524448

RESUMEN

Avaliaram-se a taxa de acúmulo foliar (TAF), a produção total de forragem (PTF), a composição química da forragem e os valores de digestibilidade in vitro da matéria seca (DIVMS) do coastcross (Cynodon dactylon) e do amendoim forrageiro (Arachis pintoi) em pastagem consorciada. Foram avaliados os tratamentos (parcelas): coastcross + A. pintoi sem nitrogênio (CA0); coastcross + A. pintoi com 100kg de nitrogênio (CA100); coastcross com 200kg de nitrogênio (C200) e coastcross + A. pintoi com 200kg de nitrogênio (CA200), e as estações (subparcelas) do ano inverno, primavera, verão e outono. Utilizou-se um delineamento experimental em blocos ao acaso, em esquema de parcelas subdivididas no tempo, com duas repetições. Os tratamentos com os maiores níveis de adubação de nitrogênio apresentaram TAF mais alto que os demais (P<0,05). No verão ocorreu a maior PTF, seguida da primavera, outono e inverno, mas estes não diferiram entre si. Não houve diferença (P>0,05) entre os tratamentos para as variáveis proteína bruta, fibra em detergente neutro e digestibilidade in vitro de matéria seca, tanto para as frações de folhas do coastcross, como para a planta inteira do A. pintoi. A adubação nitrogenada, quando aplicada à pastagem de coastcross singular ou associada ao amendoim forrageiro, proporcionou aumento da TAF e da PTF, com maior produtividade e qualidade no verão.


Forage accumulation rate (FAR), total forage production (TFP), chemical composition and in vitro dry matter digestibility (IVDMD) of coastcross pasture mixed with Arachis pintoi (AP) were evaluated. Treatments plots were: coastcross + A. pintoi without N (CA0); coastcross + A. pintoi with 100kg of N (CA100); coastcross with 200kg of N (C200); and coastcross + A. pintoi with 200kg of N (CA200); and seasons of the year (split-plots): winter, spring, summer, and autumn were analyzed. A randomized block design was used subdivided into time plots, with two replications. Treatments with the highest fertilizer levels presented higher FAR than others (P<0.05), with higher TFP during the summer, followed by spring, autumn, and winter, with no differences among then. There were no differences (P>0.05) among treatments for CP, NDF, and IVDMD on coastcross leaf fractions and Arachis pintoi whole plant. Nitrogen fertilization, when applied to single coastcross pasture or mixed with forage peanut, increased accumulation rate and forage accumulation, with higher productivity and quality in summer.

14.
J Pept Sci ; 11(7): 401-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15635670

RESUMEN

An ESR investigation of the interaction of spin-labelled penetratin with heparin, heparansulfates and several phospholipid vesicle formulations is reported. Penetratin is a 16-aa peptide corresponding to the third helix of the Antennapedia homeodomain and belonging to the cell-penetrating peptide family. The present study shows that ESR spectroscopy can provide specific and reliable information about the mechanism of interaction of penetratin with polysaccharides and lipids, at a molecular level. The study showed that: (i) heparin and heparansulfates specifically interact with spin-labelled penetratin and promote peptide aggregation and concentration on their molecular surface; (ii) penetratin does not interact with neutral lipids, whereas it enters negatively charged lipid bilayers; (iii) cholesterol plays a negative effect on the insertion of penetratin into the lipid membrane; (iv) the interaction of penetratin with lipid vesicles is strongly dependent on lipid concentration. In a low lipid regime, penetratin associates with the polar heads of phospholipids and aggregates on the membrane surface; once the lipid concentration attains a threshold, the peptide enters the lipid bilayer. This step is characterized by reduced peptide mobility and partial disaggregation.It has been shown that ESR spectroscopy is a valuable investigation tool in studies related to the still unclear mechanism of the internalization process.


Asunto(s)
Proteínas Portadoras/metabolismo , Heparina/metabolismo , Heparitina Sulfato/metabolismo , Fosfolípidos/metabolismo , Proteínas Portadoras/química , Péptidos de Penetración Celular , Colesterol/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Heparina/química , Heparitina Sulfato/química , Ligandos , Liposomas , Fosfolípidos/química , Unión Proteica
15.
Adv Drug Deliv Rev ; 55(10): 1279-91, 2003 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-14499707

RESUMEN

Synthetically produced GRF1-29 (Sermorelin) has an amino acid composition identical to the N-terminal 29 amino acids sequence of the natural hypothalamic GHRH1-44 (Figure 1). It maintains bioactivity in vitro and is almost equally effective in eliciting secretion of endogenous growth hormone in vivo. The main drawbacks associated with the pharmaceutical use of hGRF1-29 relate to its short half-life in plasma, about 10-20 min in humans, which is caused mostly by renal ultrafiltration and enzymatic degradation at the N terminus. PEGylation has been considered as one valid approach to obtain more stable forms of the peptide, with a longer in vivo half-life and ultimately with increased pharmacodynamic response along the somatotropic axis (endogenous GH, IGF-1 levels). Different PEGylated GRF conjugates were obtained and their bioactivity was tested in vitro and in vivo by monitoring endogenous growth hormone (GH) serum levels after intravenous (i.v.) injection in rats, and intravenous and subcutaneous (s.c.) injection in pigs. It was found that GRF-PEG conjugates are able to bind and activate the human GRF receptor, although with different potency. The effect of PEG molecular weight, number of PEG chains bound and position of PEGylation site on GRF activity were investigated. Mono-PEGylated isomers with a PEG5000 polymer chain linked to Lys 12 or Lys 21 residues, showed high biological activity in vitro, which is similar to that of hGRF1-29, and a higher pharmacodynamic response as compared to unmodified GRF molecule.


Asunto(s)
Polietilenglicoles/farmacología , Sermorelina , Animales , Área Bajo la Curva , Disponibilidad Biológica , Semivida , Humanos , Sermorelina/análogos & derivados , Sermorelina/metabolismo , Sermorelina/farmacocinética , Sermorelina/farmacología , Relación Estructura-Actividad
16.
J Chromatogr A ; 944(1-2): 141-8, 2002 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-11831749

RESUMEN

In this paper we report the scale-up of the purification of poly(ethylene glycol) (PEG) derivatives of the growth hormone-releasing factor 1-29, from laboratory scale (100 mg of bulk starting material) to larger scale (3 g of bulk), through the use of a cation-exchange TSK-SP-5PW chromatographic column. A one-step purification process capable of purifying large amounts of mono-PEGylated GRF species from the crude reaction mixture was developed. A simple, straightforward stepwise gradient elution separation was developed at laboratory scale and then scaled up with a larger column packed with a chromatographic resin with the same chemistry which maintained the laboratory-scale separation profile. Active material recovery and material purity remained constant through the scale-up from the 13-microm stationary phase to the 25-microm larger column. Overall, the gram GRF equivalent/batch process scale showed to be quite reproducible, and could be considered as a good platform for scale up to production scale.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Hormona Liberadora de Hormona del Crecimiento/aislamiento & purificación , Fragmentos de Péptidos/aislamiento & purificación , Polietilenglicoles/química , Resinas de Intercambio de Catión , Hormona Liberadora de Hormona del Crecimiento/química , Fragmentos de Péptidos/química , Reproducibilidad de los Resultados
17.
Immunol Lett ; 74(2): 111-5, 2000 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-10996385

RESUMEN

Tumours must avoid host immune response to survive and proliferate; to achieve this purpose, tumours interact with cells of the immune system by means of tumour secreted factors. The alterations of splenic cell populations in mice bearing the Ehrlich ascites tumour have been studied. A rapid and acute response was observed, characterized by a decrease in both CD4 and CD8 T cells, and a transient increase in the number of B cells, which peaked 2 days after tumour inoculation. An increase in macrophage population and in the homing antigen CD18 was also detected. In vitro incubations of splenic cells with the Staphylococcus aureus enterotoxin B (SEB) showed that tumour induces a state of reduced responsiveness to stimulation of T cells, mainly affecting CD8 T cells, and a diminished IFN-gamma expression.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Carcinoma de Ehrlich/inmunología , Enterotoxinas/farmacología , Bazo/citología , Bazo/inmunología , Animales , Linfocitos B/inmunología , Antígenos CD18/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Técnicas de Cultivo de Célula , Citometría de Flujo , Interferón gamma/inmunología , Activación de Linfocitos , Recuento de Linfocitos , Macrófagos/inmunología , Ratones , Trasplante de Neoplasias
18.
Biochimie ; 81(12): 1109-13, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10607405

RESUMEN

The influence of tumor implantation on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels and stability was determined in the spleen of tumor-bearing mice. While GAPDH mRNA levels were not altered in skeletal muscle, kidney and liver from tumor-bearing mice, tumor implantation led to a 5.6-fold increase in the levels of splenic GAPDH mRNA. An enhanced message stability was observed in splenocytes from tumor-bearing animals, suggesting the involvement of post-transcriptional mechanisms in the selective GAPDH mRNA accumulation after tumor implantation. The GAPDH activity/glycolytic flux ratio was 18.5 in the spleen of healthy mice. Therefore, the three-fold increase in the glycolytic flux observed after tumor implantation could hardly justify the necessity for the upregulation of GAPDH.


Asunto(s)
Carcinoma de Ehrlich/genética , Carcinoma de Ehrlich/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Bazo/metabolismo , Animales , Femenino , Glucólisis , Ratones , Estabilidad del ARN , Regulación hacia Arriba
19.
Biotechnol Bioeng ; 58(5): 510-4, 1998 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-10099287

RESUMEN

Two strains, a gram-negative bacterium Klebsiella oxytoca CECT 4460 and a gram-positive, mycelium-forming bacterium Arthrobacter globiformis CECT 4500, tolerant to up to 1 M nitrate, were isolated from the grounds of a munitions factory. Under strict aerobic conditions and with appropriate C-sources, growth of these bacteria took place when the nitrate concentration in the medium was below 150 mM. Optimal growth conditions regarding the culture medium composition for the biological removal of nitrate were established in batch cultures. Then, the system was scaled up to a 40-L pilot plant and operated under continuous conditions in a factory with direct waste streams from dinitroethylene glycol production after appropriate dilution with nontreated groundwaters. The level of nitrate in the effluent was below 0.5% of the initial N-load. Nitrite and ammonium were undetectable and the level of the C-source in the effluent was below 50 mg per L. On the basis of these results, we conclude that the system worked on site satisfactorily. Copyright 1998 John Wiley & Sons, Inc.

20.
Cancer Lett ; 133(1): 95-9, 1998 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-9929166

RESUMEN

The influence of progressive tumor growth on phosphate-activated glutaminase (PAG) expression in splenocytes from mice bearing Ehrlich ascites carcinoma cells was investigated. Implantation of Ehrlich ascites tumor cells in the peritoneal cavity of mice led to a 2.3-fold stimulation of spleen PAG activity 48 h later. Four days after tumor implantation the glutaminase activity had returned to nearly basal value and remained at this level throughout the tumor development. Northern blot analysis indicated that two species of glutaminase mRNA were expressed in the spleen, which showed a differential expression pattern during the first 2 days after tumor implantation. The abundance of the transcript of higher electrophoretic mobility (approximately 3 kb) constantly increased over the first 2 days of tumor growth. The mRNA of lower electrophoretic mobility (approximately 6 kb) peaked at 12 h after tumor implantation and returned to control values at 48 h. These results demonstrate that tumor has the capability of altering glutaminase expression in the host spleen.


Asunto(s)
Carcinoma de Ehrlich/enzimología , Regulación Enzimológica de la Expresión Génica , Glutaminasa/genética , ARN Mensajero/análisis , Bazo/enzimología , Animales , Femenino , Ratones
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