946 resultados para LOW-MOLECULAR-WEIGHT HEPARIN


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Anticoagulants are a mainstay of cardiovascular therapy, and parenteral anticoagulants have widespread use in cardiology, especially in acute situations. Parenteral anticoagulants include unfractionated heparin, low-molecular-weight heparins, the synthetic pentasaccharides fondaparinux, idraparinux and idrabiotaparinux, and parenteral direct thrombin inhibitors. The several shortcomings of unfractionated heparin and of low-molecular-weight heparins have prompted the development of the other newer agents. Here we review the mechanisms of action, pharmacological properties and side effects of parenteral anticoagulants used in the management of coronary heart disease treated with or without percutaneous coronary interventions, cardioversion for atrial fibrillation, and prosthetic heart valves and valve repair. Using an evidence-based approach, we describe the results of completed clinical trials, highlight ongoing research with currently available agents, and recommend therapeutic options for specific heart diseases.

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Theories supporting fetal origins of adult health and disease are nowadays widely accepted regarding some psychiatric conditions. However, whether genetic or environmental factors disrupting fetal growth might constitute a rick factor for depressive and/or anxious psychopathology remains still controversial.

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In vertebrates, different isoforms of fibroblast growth factor 2 (FGF2) exist, which differ by their N-terminal extension. They show different localization and expression levels and exert distinct biological effects. Nevertheless, genetic inactivation of all FGF2 isoforms in the mouse results in only mild phenotypes. Here, we analyzed mouse FGF2, and show that, as in the human, mouse FGF2 contains CTG-initiated high molecular-weight (HMW) isoforms, which contain a nuclear localization signal, and which mediate localization of this isoform to the nucleus. Using green fluorescent protein-FGF2 fusions, we furthermore observed, that C-terminal deletions disable nuclear localization of the short low-molecular-weight (LMW) 18-kDa isoform. This loss of specific localization is accompanied by a loss in heparin binding. We therefore suggest that, first, localization of mouse FGF2 is comparable to that in other vertebrates and, second, FGF2 contains at least two sequences important for nuclear localization, a nuclear localization sequence at the N terminus which is only contained in the HMW isoform, and another sequence at the C terminus, which is only required for localization of the LMW 18-kDa isoform.

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The Iowa Department of Transportation used a high molecular weight methacrylate (HMWM) resin to seal a 3,340 ft. x 64 ft. bridge deck in October 1986. The sealing was necessary to prevent deicing salt brine from entering a substantial number of transverse cracks that coincided with the epoxy coated top steel and unprotected bottom steel. HMWM resin is a three component product composed of a monomer, a curnene hydroperoxide initiator and a cobalt naphthenate promoter. The HMWM was applied with a dual spray bar system and flat-fan nozzles. Initiated monomer delivered through one spray bar was mixed in the air with promoted monomer from the other spray bar. The application rate averaged 0.956 gallons per 100 square feet for the tined textured driving lanes. Dry sand was broadcast on the surface at an average coverage of 0.58 lbs. per square yard to maintain friction. Coring showed that the H.MWM resin penetrated the cracks more than two inches deep. Testing of the treated deck yielded Friction Numbers averaging 33 with a treaded tire compared to 36 prior to treatment. An inspection soon after treatment found five leaky cracks in one of the 15 spans. One inspection during a steady rain showed no leakage, but leakage from numerous cracks occurred during a subsequent rain. A second HMWM application was made on two spans to determine if a double application would prevent leakage. This evaluation has not been completed.

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The aim of the present work was to study whole body protein synthesis and breakdown, as well as energy metabolism, in very low birth weight premature infants (less than 1500 g) during their rapid growth phase. Ten very low birth weight infants were studied during their first and second months of life. They received a mean energy intake of 114 kcal/kg X day and 3 g protein/kg X day as breast milk or milk formula. The average weight gain was 15 g/kg X day. The apparent energy digestibility was 88%, i.e. 99 kcal/kg X day. Their resting postprandial energy expenditure was 58 kcal/kg X day, indicating that 41 kcal/kg X day was retained. The apparent protein digestibility was 89%, i.e. 2.65 g/kg X day. Their rate of protein oxidation was 0.88 g/kg X day so that protein retention was 1.76 g/kg X day. There was a linear relationship between N retention and N intake (r = 0.78, p less than 0.001). The slope of the regression line indicates a net efficiency of N utilization of 67%. Estimates of body composition from the energy balance, coupled with N balance method, showed that 25% of the gain was fat and 75% was lean tissue. Whole body protein synthesis and breakdown were determined using repeated oral administration of 15N glycine for 60-72 h, and 15N enrichment in urinary urea was measured. Protein synthesis averaged 11.2 g/kg X day and protein breakdown 9.4 g/kg X day. Muscular protein breakdown, as estimated by 3-methylhistidine excretion, contributed to 12% of the total protein breakdown.(ABSTRACT TRUNCATED AT 250 WORDS)

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Identification of neuroimaging biomarkers following extreme prematurity (EP) and intrauterine growth restriction (IUGR) is crucial for understanding their cognitive and behavioral impairments at school age

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An overview of the current literature on the chemical processes involved in the ion formation from low molecular weight organic compounds by electrospray ionization mass spectrometry is given.

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In recent years, one important objective of cardiovascular research has been to find new markers that would improve the risk stratification and diagnosis of patients presenting with symptoms of acute coronary syndrome (ACS). Pregnancy-associated plasma protein A (PAPP-A) is a large metalloproteinase involved in insulin-like growth factor signalling. It is expressed in various tissues and seems to be involved in many physiological and pathological processes, such as folliculogenesis, bone formation, wound healing, pregnancy and atherosclerosis. The aim of this thesis was to investigate PAPP-A in ACS patients. Circulating concentrations of PAPP-A had been previously shown to be elevated in ACS. In this study it was revealed that the form of PAPP-A causing this elevation was the free noncomplexed PAPP-A. Thus, the form of PAPP-A in the circulation of ACS patients differed from the complexed PAPP-A form abundantly present in the circulation during pregnancy. A point-of-care method based on time-resolved immunofluorometric assays was developed, which enabled the rapid detection of free PAPP-A. The method was found to perform well with serum and heparin plasma samples as well as with heparinized whole blood samples. With this method the concentrations of free PAPP-A in healthy individuals were shown to be negligible. When the clinical performance of the method was evaluated with serum samples from ACS patients, it was shown that the free PAPP-A concentration in the admission sample was an independent predictor of myocardial infarction and death. Moreover, as a prognostic marker, free PAPP-A was revealed to be superior to total PAPPA, i.e. the combination of free and complexed PAPP-A, which has been measured by the other groups in this field. As heparin products are widely used as medication in ACS patients, the effect of heparin products on free PAPP-A molecule and circulating concentrations were also investigated in this study. It was shown that intravenous administration of low molecular weight or unfractionated heparin elicits a rapid release of free PAPP-A into the circulation in haemodialysis patients and patients undergoing angiography. Moreover, the interaction between PAPP-A and heparin was confirmed in gel filtration studies. Importantly, the patients included in the clinical evaluation of the free PAPP-A detection method developed had not received any heparin product medication before the admission sample and thus the results were not affected by the heparin effect. In conclusion, free PAPP-A was identified as a novel marker associated with ACS. The point-of-care methods developed enable rapid detection of this molecule which predicts adverse outcome when measured in the admission sample of ACS patients. However, the effect revealed of heparin products on circulating PAPP-A concentrations should be acknowledged when further studies are conducted related to free or total PAPP-A in ACS.

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Alternatives for the removal of high-molecular weight polycyclic aromatic hydrocarbons (HWM-PAH) from soil were tested by adding fertilizer or glycerol, as well as the combination of both. Experiments were carried out for 60 days in reactors containing a HWM-PAH-contaminated soil (8030 μg kg-1), accompanied by pH monitoring, humidity control and quantification of total heterotrophic bacteria and total fungus. Fertilizer addition removed 41.6% of HWM-PAH. Fertilizer and glycerol in combination removed 46.2%. When glycerol was added individually, degradation reached 50.4%. Glycerol also promoted the increase of degradation rate during the first 30 days suggesting the HMW-PAH removal occurred through cometabolic pathways.

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The survival of preterm born infants has increased but the prevalence of long-term morbidities has still remained high. Preterm born children are at an increased risk for various developmental impairments including both severe neurological deficits as well as deficits in cognitive development. According to the literature the developmental outcome perspective differs between countries, centers, and eras. Definitions of preterm infant vary between studies, and the follow-up has been carried out with diverse methods making the comparison less reliable. It is essential to offer parents upto-date information about the outcome of preterm infants born in the same area. A centralized follow-up of children at risk makes it possible to monitor the consequences of changes in the treatment practices of hospitals on developmental outcome. This thesis is part of a larger regional, prospective multidisciplinary follow-up project entitled “Development and Functioning of Very Low Birth Weight Infants from Infancy to School Age” (PIeniPAinoisten RIskilasten käyttäytyminen ja toimintakyky imeväisiästä kouluikään, PIPARI). The thesis consists of four original studies that present data of very low birth weight (VLBW) infants born between 2001 and 2006, who are followed up from the neonatal period until the age of five years. The main outcome measure was cognitive development and secondary outcomes were significant neurological deficits (cerebral palsy, CP, deafness, and blindness). In Study I, the early crying and fussing behavior of preterm infants was studied using parental diaries, and the relation of crying behavior and cognitive and motor development at the age of two years was assessed. In Study II, the developmental outcome (cognitive, CP, deafness, and blindness) at the age of two years was studied in relation to demographic, antenatal, neonatal, and brain imaging data. Development was studied in relationship to a full-term born control group born in the same hospital. In Study III, the stability of cognitive development was studied in VLBW and full-term groups by comparing the outcomes at the ages of two and five years. Finally, in Study IV the precursors of reading skills (phonological processing, rapid automatized naming, and letter knowledge) were assessed for VLBW and full-term children at the age of five years. Pre-reading skills were studied in relation to demographic, antenatal, neonatal, and brain imaging data. The main findings of the thesis were that VLBW infants who fussed or cried more in the infancy were not at greater risk for problems in their cognitive development. However, crying was associated with poorer motor development. The developmental outcome of the present population was better that has been reported earlier and this improvement covered also cognitive development. However, the difference to fullterm born peers was still significant. Major brain pathology and intestinal perforation were independent significant risk factors for adverse outcome, also when several individual risk factors were controlled for. Cognitive development at the age of two years was strongly related with development at the age of five years, stressing the importance of the early assessment, and the possibility for early interventions. Finally, VLBW children had poorer pre-reading skills compared with their full-term born peers, but the IQ was an important mediator even when children with mental retardation were excluded from the analysis. The findings suggest that counseling parents about the developmental perspectives of their preterm infant should be based on data covering the same birth hospital. Neonatal brain imaging data and neonatal morbidity are important predictors for developmental outcome. The findings of the present study stress the importance of both short-term (two years) and long-term (five years) follow-ups for the individual, and for improving the quality of care.

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Bread-making quality is one of the most important targets in the genetic improvement of wheat. Although extensive analyses of quality traits such as farinography, sodium dodecyl sulfate (SDS) sedimentation, alveography, and baking are made in breeding programs, these analyses require high amounts of seeds which are obtained only in late generations. In this experiment the statistical correlations between the high molecular weight subunit of glutenin and bread-making quality measured by alveograph, farinograph and SDS sedimentation were evaluated. Seventeen wheat genotypes were grown under the same conditions, each producing about 1 kg of seeds for the evaluations. The high molecular weight (HMW) glutenin subunits were analyzed by SDS-PAGE. Statistical correlations were highly significant between HMW glutenin subunits and alveograph and SDS sedimentation. These results indicate the possibility of manipulating major genes for wheat seed quality by coupling traditional breeding with non-destructive single seed analysis. Only half seed is necessary to perform the SDS-PAGE analysis. Therefore, the other half seed can be planted to generate the progeny. Seed yield and SDS sedimentation were statistically correlated, indicating the possibility of simultaneous selection for both traits

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Carbon nanotubes are highly versatile materials; new applications using them are continuously being developed. Special attention is being dedicated to the possible use of multiwalled carbon nanotubes in biomaterials contacting with bone. However, carbon nanotubes are also controversial in regards to effects exerted on living organisms. Carbon nanotubes can be used to improve the tribological properties of polymer/composite materials. Ultrahigh molecular weight polyethylene (UHMWPE) is a polymer widely used in orthopedic applications that imply wear and particle generation. We describe here the response of human osteoblast-like MG63 cells after 6 days of culture in contact with artificially generated particles from both UHMWPE polymer and multiwalled carbon nanotubes (MWCNT)/UHMWPE nanocomposites. This novel composite has superior wear behavior, having thus the potential to reduce the number of revision hip arthroplasty surgeries required by wear failure of acetabular cups and diminish particle-induced osteolysis. The results of an in vitro study of viability and proliferation and interleukin-6 (IL-6) production suggest good cytocompatibility, similar to that of conventional UHMWPE (WST-1 assay results are reported as percentage of control ± SD: UHMWPE = 96.19 ± 7.92, MWCNT/UHMWPE = 97.92 ± 8.29%; total protein: control = 139.73 ± 10.78, UHMWPE = 137.07 ± 6.17, MWCNT/UHMWPE = 163.29 ± 11.81 µg/mL; IL-6: control = 90.93 ± 10.30, UHMWPE = 92.52 ± 11.02, MWCNT/UHMWPE = 108.99 ± 9.90 pg/mL). Standard cell culture conditions were considered as control. These results, especially the absence of significant elevation in the osteolysis inductor IL-6 values, reinforce the potential of this superior wear-resistant composite for future orthopedic applications, when compared to traditional UHMWPE.