Procedural Differences (procedural + difference)

Distribution by Scientific Domains


Selected Abstracts


Adapted DAX-8 fractionation method for dissolved organic matter (DOM) from soils: development, calibration with test components and application to contrasting soil solutions

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2009
F. Amery
Summary Most methods to fractionate natural dissolved organic matter (DOM) rely on sorption of acidified DOM samples onto XAD-8 or DAX-8 resin. Procedural differences among methods are large and their interpretation is limited because there is a lack of calibration with DOM model molecules. An automated column-based DOM fractionation method was set up for 10-ml DOM samples, dividing DOM into hydrophilic (HPI), hydrophobic acid (HPOA) and hydrophobic neutral (HPON) fractions. Fifteen DOM model components were tested in isolation and in combination. Three reference DOM samples of the International Humic Substances Society were included to facilitate comparison with other methods. Aliphatic low-molecular-weight acids (LMWAs) and carbohydrates were classified as HPI DOM, but some LMWAs showed also a partial HPO character. Aromatic LMWAs and polyphenols partitioned in the HPOA fraction, menadione (quinone) and geraniol (terpenoid) in HPON DOM. Molecules with log Kow > 0.5 had negligible HPI fractions. The HPO molecules except geraniol had specific UV absorbance (SUVA, measure for aromaticity) >3 litres g,1 cm,1 while HPI molecules had SUVA values <3 litres g,1 cm,1. Distributions of DOM from eight soils ranged from 31 to 72% HPI, 25 to 46% HPOA and 2 to 28% HPON of total dissolved organic carbon. The SUVA of the HPI DOM was consistently smaller compared with the HPOA DOM. The SUVA of the natural DOM samples was not explained statistically by fractionation and the variation coefficient of SUVA among samples was not reduced by fractionation. Hence, fractionation did not reduce the variability in this DOM property, which casts some doubts on the practical role of DOM fractionation in predicting DOM properties. [source]


Local regulation of human breast xenograft models,,

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2010
Jodie M. Fleming
Breast cancer studies implant human cancer cells under the renal capsule, subcutaneously, or orthotopically and often use estrogen supplementation and immune suppressants (etoposide) in xenograft mouse models. However, cell behavior is significantly impacted by signals from the local microenvironment. Therefore, we investigated how the combinatorial effect of the location of injection and procedural differences affected xenograft characteristics. Patient-derived breast cancer cells were injected into mouse abdominal or thoracic mammary glands,±,estrogen and/or etoposide pretreatment. Abdominal xenografts had increased tumor incidence and volume, and decreased latency (P,<,0.001) compared to thoracic tumors. No statistically significant difference in tumor volume was found in abdominal xenografts treated,±,estrogen or etoposide; however, etoposide suppressed tumor volume in thoracic xenografts (P,<,0.02). The combination of estrogen and etoposide significantly decreased tumor incidence in both sites. In addition, mice treated,±,estradiol were injected orthotopically or subcutaneously with well-characterized breast cancer cell lines (MCF7, ZR75-1, MDA MB-231, or MCF10Ca1h). Orthotopic injection increased tumor volume; growth varied with estrogen supplementation. Location also altered methylation status of several breast cancer-related gene promoters. Lastly, vascularization of orthotopic tumors was significantly enhanced compared to subcutaneous tumors. These data suggest that optimal xenograft success occurs with orthotopic abdominal injections and illustrate molecular details of the compelling influence of the local microenvironment on in vivo models. J. Cell. Physiol. 224: 795,806, 2010. Published 2010 Wiley-Liss, Inc. [source]


Use and practice of patient diaries in Swedish intensive care units: a national survey

NURSING IN CRITICAL CARE, Issue 1 2010
Eva Åkerman
Aims and objectives: To describe and compare the extent and application of patients' diaries in Sweden. Background: Since 1991, patient diaries have been used in intensive care unit (ICU) follow-up in Sweden. There is paucity of relevant data evaluating the effect of this tool and also on what premises patients are enrolled. Likewise, data are sparse on the diaries' design, content structure and the use of photographs. Design: Descriptive explorative design by a semi-structured telephone interview. Methods: The interview results were analysed with descriptive statistics and differences between the ICU levels were explored by ,2 analysis. Qualitative manifest content analysis was performed to explore the purpose of diary writing. Results: Of all ICUs (n = 85), 99% responded and 75% used diaries. The source of inspiration was collegial rather than from scientific data. The main reason for keeping a diary was to help the patient to recapitulate the ICU stay. Discrepancies between the different levels of ICUs were detected in patient selection, dedicated staff for follow-up and the use of photographs. Comparison between the ,2 analysis and the content analysis outcome displayed incongruence between the set unit-goals and the activities for achievement but did not explain the procedural differences detected. Conclusion: The uses of diaries in post ICU follow up were found to be common in Sweden. A majority used defined goals and content structure. However, there were differences in practice and patient recruitment among the levels of ICUs. These discrepancies seemed not to be based on evidence-based data nor on ongoing research or evaluation but merely on professional judgement. As ICU follow-up is resource intense and time consuming, it is paramount that solid criteria for patient selection and guidelines for the structure and use of diaries in post-ICU follow-up are defined. [source]


Conscious or deep sedation: a questionnaire regarding the experience of parents, children and staff during small bowel biopsy

ACTA PAEDIATRICA, Issue 6 2003
J Skoglösa
Aim: The paediatric clinics of Linköping and Norrköping, Sweden, have different procedures regarding premedication and sedation during small bowel biopsy in children with suspected or diagnosed coeliac disease. In Linköping deep sedation using intravenous propofol is the method of sedation being used and parents are not present during the biopsy procedure. In Norrköping conscious sedation using intravenous midazolam is the routine and parents stay with their child throughout the whole biopsy procedure. The aim of this study was to find out whether the preprocedural and procedural differences between the clinics affected the way in which the parents and children experienced the time before and during the biopsy procedure. Methods: A questionnaire was used to ask the parents of 102 children who had undergone small bowel capsule biopsy for their opinion regarding the discomfort experienced by their children. The parents'and children's experience was also compared with that of the paediatric nurse caring for the family during the biopsy procedure, and the paediatric gastroenterologist performing the biopsy. Results: The differences regarding premedication and sedation between the two groups did not seem to affect the parents'or the children's total experience of the biopsy procedure, nor did the presence or absence of the parents throughout the biopsy procedure. As regards the sedation given, 95% of the parents did not think that their children suffered any discomfort at all. The total experience of the biopsy procedure on a five-grade scale (5 being very good, 1 being very bad) was 5 for the parents and 4 for the children in both centres. Parents and children in both centres were very satisfied with the way in which they were taken care of during their visit to the hospital. In both units there was an obvious correlation between how the paediatric nurse experienced the biopsy procedure and how the paediatric gastroenterologist did, but only a weak correlation between the experience of the parents and that of the paediatric gastroenterologist and paediatric nurse. The anxiety of the parents was similarly estimated by the paediatric gastroenterologist and the paediatric nurse in both centres. There was no correlation between their assessment and the experience reported by the parents. Conclusion: The children undergoing small bowel biopsy and their parents felt well taken care of during their visit to the two hospitals. The differences between the clinics regarding method of sedation and presence or absence of the parents did not seem to affect how the parents and children experienced the biopsy procedure. [source]