Search results for "Gela"
showing 10 items of 242 documents
Monolītiska silīcija dioksīda iegūšana ar sola-gela metodi
2021
Darbā pilnveidota SiO2 sola-gela sintēzes metode ar mērķi iegūt monolītiskus, optiski caurspīdīgus, nesaplaisājušus paraugus. SiO2 paraugu konsolidācijas process pētīts, tos pakāpeniski izkarsējot gaisā, skābeklī vai ūdeņradī. SiO2 paraugu īpašību pētījumos izmantotas struktūranalīzes, termogravimetrijas, optiskās spektroskopijas un elektronu mikroskopijas metodes. Darbā iegūts stiklveida monolītisks SiO2, pie termiskās apstrādes temperatūrām 600 °C un augstākām. Sintezētajos paraugos novērota palielināta 3-locekļu SiO2 saišu gredzenu koncentrācija, kā arī brīvās un ar ūdeņraža saiti saistītās silanolgrupas (Si-O-H). Silanolgrupu koncentrāciju iespējams samazināt, karsējot paraugu 1000 °C –…
Zymographic analysis of circulating and tissue forms of colon carcinoma gelatinase A (MMP-2) and B (MMP-9) separated by mono- and two-dimensional ele…
2001
Gelatinase A (MMP-2) and gelatinase B (MMP-9) play a key role in the proteolytic cascade leading to ECM degradation during invasion and metastasis. The enzyme activity is regulated both at the intra- and extra-cellular level. Extracellular regulation is achieved mainly through the balance between proenzyme activation and inhibition, which appears to be altered in cancer patients. One of the mechanisms of MMP inhibition is the binding of the enzymes to appropriate tissue inhibitors (TIMP). In the recent literature, it has been suggested that MMP-2 and/or MMP-9 are indeed over-produced in many carcinomas, while the identity of the various enzymatic forms (latent, activated and enzyme/inhibito…
Lipid Peroxidation, Protein Oxidation, Gelatinases, and Their Inhibitors in a Group of Adults with Obesity
2019
AbstractThe association between obesity and cardiovascular diseases has a multifactorial pathogenesis, including the synthesis of inflammatory molecules, the increase in oxidative stress and the dysregulation of the matrix metalloprotease (MMP) concentration and activity. In a group of adults with obesity, divided in 2 subgroups according to the body mass index (BMI), we examined lipid peroxidation, expressed as thiobarbituric acid-reactive substances (TBARS), protein oxidation, expressed as protein carbonyl groups (PCs), plasma gelatinases (MMP-2 and MMP-9), and their tissue inhibitors (TIMP-1 and TIMP-2). In the whole group, as well as in the 2 subgroups (with BMI 30–35 or BMI>35) of o…
Variation of serum and urinary neutrophil gelatinase associated lipocalin (NGAL) after strenuous physical exercise.
2012
AbstractStrenuous exercise may trigger acute complications, such as exertional rhabdomyolysis and gastrointestinal complaint. As less is known about the potential renal impairment after long distance running, we assessed creatinine and neutrophil gelatinase associated lipocalin (NGAL) in serum (sNGAL) and urine (uNGAL) before and after an ultramarathon.The study population consisted of 16 trained male athletes who ran a 60 km ultramarathon. Blood and spot urine samples were collected 20 min before and immediately after the run. Creatinine was assessed by Jaffe assay on Beckman Coulter AU5800 and renal function was expressed as estimated glomerular filtration rate (eGFR) by MDRD formula. NGA…
A gelatin-thrombin matrix topical hemostatic agent (Floseal) in combination with harmonic scalpel is effective in patients undergoing total thyroidec…
2016
BACKGROUND: Hemostasis during thyroidectomy is essential; however, the safest, most efficient, and most cost-effective way to achieve this is unclear. This randomized, multicenter, single-blind, prospective study evaluated the efficacy and safety of using different hemostatic approaches in patients undergoing total thyroidectomy. METHODS: Patients aged ≥18 to 70 years were randomized to Floseal + a harmonic scalpel (HS), Floseal alone, HS alone, or standard total thyroidectomy. Primary endpoint was 24-hour drain output. Secondary endpoints included surgery duration and complications. RESULTS: Two hundred and six patients were randomized to Floseal + HS (n = 52), Floseal alone (n = 54), HS a…
Centaurea aspera subsp. geladensis, subsp. nov. (sect. seridia (Juss.) DC., Asteraceae), un nuevo taxon para la flora valenciana
2018
Se describe una nueva subespecie de Centaurea aspera L. (sect. Seridia (Juss.) DC., Asteraceae) procedente de las dunas fósiles del Parque Natural de Serra Gelada (L’Alfàs del Pi y Benidorm, Alicante, España). Se proporcionan datos morfológicos y ecológicos que permiten la diferenciación de la nueva subespecie con sus dos parientes cercanos C. aspera subsp. aspera y C. aspera subsp. stenophylla. A new subspecies of Centaurea aspera L. (sect. Seridia (Juss.) DC., Asteraceae) is described from the fossil dunes of Serra Gelada Natural Park (L’Alfàs del Pi and Benidorm, Alicante, Spain). Morphological and ecological data are provided which allow differentiation from the close relatives C. asper…
Stability and bioaccessibility of EGCG within edible micro-hydrogels. Chitosan vs. gelatin, a comparative study
2016
Micro-hydrogels are very promising systems for the protection and controlled delivery of sensitive bioactives, but limited knowledge exists regarding the impact of this encapsulation on their bioaccessibility. In this work, two different hydrogel-forming biopolymers (gelatin and chitosan) were compared as wall materials for the microencapsulation of a model flavonoid, (−)-epigallocatechin gallate (EGCG). Results showed that gelatin was more adequate as wall material for the encapsulation of EGCG than chitosan, achieving higher encapsulation efficiencies (95% ± 6%), being more effective in delaying EGCG release and degradation in aqueous solution and exhibiting a 7 times higher bioaccessibil…
The ice nucleating ability of pollen:
2002
Abstract Laboratory tests were conducted of the ice nucleating ability of four kinds of pollen in the immersion and the contact freezing modes. The diameters of the selected pollen were between 25 and 70 μm. The experiments were carried out at the Mainz vertical wind tunnel with freely suspended supercooled droplets at temperatures down to −28 °C. The immersion freezing experiments were conducted with drops of radii between 250 and 375 μm formed from distilled water with a defined amount of pollen added. The drops were freely floated in the wind tunnel while being supercooled. For the contact freezing experiments, a short burst of pollen was allowed to collide with freely suspended, superco…
The ice nucleating ability of pollen
2001
Abstract Laboratory experiments are described where the water uptake by a variety of pollen was studied quantitatively, followed by the investigation of the ice nucleating ability of four kinds of pollen in the deposition and the condensation freezing modes. The diameters of the pollen selected for the freezing experiments were between 25 and 70 μm. The freezing experiments in the deposition mode including also pollen resuspended from decayed leaves, and crushed pollen grains were carried out at different temperatures down to −33 °C combined with various supersaturations with respect to ice up to 35%. The condensation freezing experiments were carried out at temperatures down to −18 °C at s…