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101.
Abstract A multidisciplinary field study investigating the fate and transport of petroleum hydrocarbons commonly associated with jet-fuel contamination is currently underway at Columbus Air Force Base (AFB), Mississippi. Sixty sediment cores from 12 boreholes were recovered from the study aquifer. The goal of this initial sampling was to characterize the potential microbial activity using 14C-labeled substrates, as well as the presence, abundance, and distribution of specific hydrocarbon degrading genotypes using DNA:DNA hybridization. Enumeration of total microbial abundance using a 16S rDNA universal oligonucleotide probe was compared to traditional enumeration methods. Total culturable populations determined by spread plate analysis ranged from a low of 10(4) to more than 10(6) organisms per gram sediment. Microbial abundance estimated by DNA hybridization studies with 16S rDNA genes ranged from 10(7) to 10(8) organisms per gram sediment. Molecular analysis of aquifer samples using DNA probes targeting genes encoding the degradative enzymes alkane hydroxylase (alkB), catechol 2,3-dioxygenase (nahH), naphthalene dioxygenase (nahA), toluene dioxygenase (todC1C2), toluene monooxygenase (tomA), and xylene monooxygenase (xylA), as well as two probes measuring methanogenic microorganisms, codh (carbon monoxide dehydrogenase) and mcr (methyl coenzyme reductase), revealed that each target gene sequence was present in nearly all 60 samples. The presence of organisms demonstrating the phenotype to degrade BTEX and naphthalene was further supported using mineralization assays with 14C-labeled benzene, toluene, naphthalene, and phenanthrene. Minimal activity occurred during the first 24 hours. After a period of 5-7 days, greater than 40% of the target compounds were mineralized in aquifer sediments. 相似文献
102.
The acidic glycolipid fraction (AF) of the porcine, parasitic nematode,
Ascaris suum , consisted of two subfractions. The major component AF II
reacted with orcinol-sulfuric acid and molybdate, while the minor component
AF I gave a positive reaction with azure-A, a cationic dye specific for
sulfatides. Sugar constituent analysis, methanolysis, methylation analysis,
matrix-assisted laser desorption/ionization time- of-flight mass
spectrometry, liquid secondary-ion mass spectrometry, and gas-liquid
chromatography/mass spectrometry specified AF II to be an unusual
phosphoinositolglycosphingolipid (Galalpha1-Ins-P-1ceramide) and the minor
component AF I to be a 3-sulfogalactosylcerebroside (HSO3-
3Galss1-1ceramide). The ceramide moiety of both components consisted of
lignoceric (C24:0) and cerebronic (C24h:0) acids and mainly C17 iso-
branched sphingosine. Immunohistochemical localization studies of the
glycolipid-bound antigenic determinants with a polyclonal antiserum against
AF II and an anti-sulfatide monoclonal antibody against AF I revealed the
presence of the AF II-epitope in the intestine, whereas the AF I-epitope
was found in the hypodermis, contractile zone of somatic muscle cells and
the external musculature of the uterus. To our knowledge, this is the first
report of the presence of a sulfatide in an invertebrate.
相似文献
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105.
Competency is an important concept in medical ethics as well as in law. It refers to the moral principles of self-determination and autonomy, which are of central importance in the ethics of health care. These moral principles also prevail in nursing home care. Societal prejudice concerning nursing home patients suggests that the inhabitants of a nursing home are almost by definition incompetent. We assert that such prejudice rests on certain societal delusions and misinterpretations of incompetency five of which are subsequently analysed. Next we discuss the dominant conception of competency in terms of decisional capacity. This conception is predominantly oriented towards cognitive abilities and underplays affective capacities. We confront this dominant conception with an alternative proposal of competency in terms of 'the capacity to value', which--to our opinion--more properly reflects nursing home practice concerning questions of competency. Finally we address the limitations of any concept of competency or decisional capacity in relation to the moral issues of 'good care' for demented elderly. As an alternative we draw attention to the moral perspective of the 'ethics of care'. 相似文献
106.
Hinck L Van Der Smissen P Heusterpreute M Donnay I De Hertogh R Pampfer S 《Biology of reproduction》2001,64(2):555-562
107.
Palliative care in dementia and the dismantlement of nursing home medicinePalliative care is mostly restricted to the terminal phase of incurable illness. According to the WHO revised definition palliative care is specifically directed towards patients and families facing life-threatening illness. This definition is not adequate to orient and direct palliative care policies in non-cancer diseases such as dementia. Although dementia is incurable from the outset, its course is often protracted, resulting in a terminal stage only after several years. This disease trajectory necessitates an alternative palliative approach, implying a proactive attitude of nursing home physicians in facilitating early and timely discussions with patients and their proxies on advance care planning and treatment of complications and concomitant diseases. This, together with their specific training in the treatment of the long term sequelae of chronic diseases, defines the success of Dutch nursing home medicine in foregoing inappropriate hospital admissions and providing adequate medical care in the nursing home. However, recent reorganisations of nursing home care and its funding threaten to downgrade the quality of medical care for patients with dementia in Dutch nursing homes by focusing unilaterally on welfare ideology and ‘marketization’ of long term care, thus underestimating the importance of a palliative care policy in dementia. 相似文献
108.
RD Calixto R Verlengia AH Crisp TB Carvalho MD Crepaldi AA Pereira AK Yamada GR da Mota CR Lopes 《Biology of sport / Institute of Sport》2014,31(4):289-294
This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL−1) relative to the FEV group (0.1 ± 0.0 ng · mL−1). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response. 相似文献
109.
Tatsuhiro Masaoka Tim Vanuytsel Christophe Vanormelingen Sebastien Kindt Shadea Salim Rasoel Werend Boesmans Gert De Hertogh Ricard Farré Pieter Vanden Berghe Jan Tack 《PloS one》2014,9(5)
Background and Aims
Recent reports indicate the presence of low grade inflammation in functional gastrointestinal disorders (FGID), in these cases often called “post-inflammatory” FGIDs. However, suitable animal models to study these disorders are not available. The Biobreeding (BB) rat consists of a diabetes-resistant (BBDR) and a diabetes-prone (BBDP) strain. In the diabetes-prone strain, 40–60% of the animals develop diabetes and concomitant nitrergic dysfunction. Our aim was to investigate the occurrence of intestinal inflammation, nitrergic dysfunction and intestinal dysmotility in non-diabetic animals.Methods
Jejunal inflammation (MPO assay, Hematoxylin&Eosin staining and inducible nitric oxide synthase (iNOS) mRNA expression), in vitro jejunal motility (video analysis) and myenteric neuronal numbers (immunohistochemistry) were assessed in control, normoglycaemic BBDP and diabetic BBDP rats. To study the impact of iNOS inhibition on these parameters, normoglycaemic BBDP rats were treated with aminoguanidine.Results
Compared to control, significant polymorphonuclear (PMN) cell infiltration, enhanced MPO activity, increased iNOS mRNA expression and a decreased ratio of nNOS to Hu-C/D positive neurons were observed in both normoglycaemic and diabetic BBDP rats. Aminoguanidine treatment decreased PMN infiltration, iNOS mRNA expression and MPO activity. Moreover, it restored the ratio of nNOS to Hu-C/D positive nerves in the myenteric plexus and decreased the abnormal jejunal elongation and dilation observed in normoglycaemic BBDP rats.Conclusions
Aminoguanidine treatment counteracts the inflammation-induced nitrergic dysfunction and prevents dysmotility, both of which are independent of hyperglycaemia in BB rats. Nitrergic dysfunction may contribute to the pathophysiology of “low-grade inflammatory” FGIDs. Normoglycaemic BBDP rats may be considered a suitable animal model to study the pathogenesis of FGIDs. 相似文献110.
Benoît De Hertogh Bertrand De Meulder Fabrice Berger Michael Pierre Eric Bareke Anthoula Gaigneaux Eric Depiereux 《BMC bioinformatics》2010,11(1):17