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231.
Cecilia Hermansson Annika Lundqvist Carina Wasslavik Lars Palmqvist Anders Jeppsson Lillemor Mattsson Hultén 《Biochemical and biophysical research communications》2013,430(1):425-428
The innate immune system and, in particular, activation of the multi-protein complex known as the inflammasome complex are involved in ischemic injury in myocardial cells. The nucleotide-binding leucine-rich repeat-containing pyrin receptor 3 (NLRP3) inflammasome has been linked to inflammation and NLRP3 is especially important for increased inflammation in atherosclerosis, which may lead to myocardial infarction. Here we investigated how inflammasome molecules are affected in human ischemic heart tissue. Surprisingly the important member of the inflammasome complex, NLRP3, displayed markedly decreased levels in human ischemic heart tissue compared with non ischemic control heart tissue. However, subsequent gene analysis revealed mutations in NLRP3 in human ischemic heart tissues but not in non-ischemic control tissue. Gene polymorphisms in the NLRP3 inflammasome have been shown to be associated with increased IL-1β and IL-18 production and severe inflammation.The autoinflammatory disorder familial Mediterranean fever (FMF) is associated with decreased expression of the Mediterranean fever gene (MEFV) and increased inflammation. We also observed reduced expression of MEFV in ischemic versus non-ischemic heart tissue. Further analyses showed a mutation in MEFV in human ischemic heart tissue but not in non-ischemic control tissue.Our data show that defects in the inflammasome and associated proteins may be involved in promoting ischemic heart disease. 相似文献
232.
Elisavet Georgiadou Kristina Eriksson Stenström Cintia Bertacchi Uvo Peter Nilsson Göran Skog Sören Mattsson 《Radiation and environmental biophysics》2013,52(2):175-187
The 14C content of 60 human blood serum samples from residents of Malmö (Sweden) in 1978, obtained from a biobank, has been measured to estimate the accuracy of 14C bomb-pulse dating. The difference between the date estimated using the Calibomb software and sampling date varied between ?3 ± 0.4 and +0.2 ± 0.5 years. The average age deviation of all samples was ?1.5 ± 0.7 years, with the delay between production and consumption of foodstuffs being probably the dominating cause. The potential influence of food habits on the 14C date has been evaluated using stable isotope δ13C and δ15N analysis and information about the dietary habits of the investigated individuals. Although the group consisting of lacto-ovo vegetarians and vegans (pooled group) was not completely separated from the omnivores in a stable isotopic trophic level diagram, this analysis proved to add valuable information on probable dietary habits. The age deviation of the sampling date from the respective Calibomb date was found strongly correlated with the δ13C values, probably due to influence from marine diet components. For the omnivore individuals, there were indications of seasonal effects on δ13C and the age deviation. No significant correlation was found between the age deviation and the δ15N values of any dietary group. No influence of sex or year of birth was found on neither the 14C nor the δ13C and δ15N values of the serum samples. The data were also divided into two groups (omnivores and pooled group), based on the level of δ15N in the samples. The consumption of high δ15N-valued fish and birds can be responsible for this clustering. 相似文献
233.
Niklas Mattsson Philip Insel Duygu Tosun Jing Zhang Clifford R. Jack Jr Douglas Galasko Michael Weiner for the Alzheimer’s Disease Neuroimaging Initiative 《PloS one》2013,8(12)
Background
Cerebrospinal fluid (CSF) α-synuclein is reduced in synucleinopathies, including dementia with Lewy bodies, and some studies have found increased CSF α-synuclein in Alzheimer’s disease (AD). No study has explored effects of CSF α-synuclein on brain atrophy. Here we tested if baseline CSF α-synuclein affects brain atrophy rates and if these effects vary across brain regions, and across the cognitive spectrum from healthy elders (NL), to patients with mild cognitive impairment (MCI) and AD.Methods
Baseline CSF α-synuclein measurements and longitudinal structural brain magnetic resonance imaging was performed in 74 NL, 118 MCI patients and 55 AD patients. Effects of baseline CSF α-synuclein on regional atrophy rates were tested in 1) four pre-hoc defined regions possibly associated with Lewy body and/or AD pathology (amygdala, caudate, hippocampus, brainstem), and 2) all available regions of interest. Differences across diagnoses were tested by assessing the interaction of CSF α-synuclein and diagnosis (testing NL versus MCI, and NL versus AD).Results
The effects of CSF α-synuclein on longitudinal atrophy rates were not significant after correction for multiple comparisons. There were tendencies for effects in AD in caudate (higher atrophy rates in subjects with higher CSF α-synuclein, P=0.046) and brainstem (higher atrophy rates in subjects with lower CSF α-synuclein, P=0.063). CSF α-synuclein had significantly different effects on atrophy rates in NL and AD in brainstem (P=0.037) and caudate (P=0.006). Discussion: With the possible exception of caudate and brainstem, the overall weak effects of CSF α-synuclein on atrophy rates in NL, MCI and AD argues against CSF α-synuclein as a biomarker related to longitudinal brain atrophy in these diagnostic groups. Any effects of CSF α-synuclein may be attenuated by possible simultaneous occurrence of AD-related neuronal injury and concomitant Lewy body pathology, which may elevate and reduce CSF α-synuclein levels, respectively. 相似文献234.
235.
236.
Johanna M. Mattsson Suvi Ravela Can Hekim Magnus Jonsson Johan Malm Ale N?rv?nen Ulf-H?kan Stenman Hannu Koistinen 《PloS one》2014,9(9)
Prostate-specific antigen (PSA or kallikrein-related peptidase-3, KLK3) exerts chymotrypsin-like proteolytic activity. The main biological function of PSA is the liquefaction of the clot formed after ejaculation by cleavage of semenogelins I and II in seminal fluid. PSA also cleaves several other substrates, which may explain its putative functions in prostate cancer and its antiangiogenic activity. We compared the proteolytic efficiency of PSA towards several protein and peptide substrates and studied the effect of peptides stimulating the activity of PSA with these substrates. An endothelial cell tube formation model was used to analyze the effect of PSA-degraded protein fragments on angiogenesis. We showed that PSA degrades semenogelins I and II much more efficiently than other previously identified protein substrates, e.g., fibronectin, galectin-3 and IGFBP-3. We identified nidogen-1 as a new substrate for PSA. Peptides B2 and C4 that stimulate the activity of PSA towards small peptide substrates also enhanced the proteolytic activity of PSA towards protein substrates. Nidogen-1, galectin-3 or their fragments produced by PSA did not have any effect on endothelial cell tube formation. Although PSA cleaves several other protein substrates, in addition to semenogelins, the physiological importance of this activity remains speculative. The PSA levels in prostate are very high, but several other highly active proteases, such as hK2 and trypsin, are also expressed in the prostate and may cleave protein substrates that are weakly cleaved by PSA. 相似文献
237.
Background
In 1951 Churg and Strauss first described the clinical condition now known as eosinophilic granulomatosis with polyangiitis (EGPA), characterized by asthma, nasal polyposis, rhinosinusitis, hypereosinophilia with organ infiltration, and necrotizing vasculitis. It is classified as an antineutrophil cytoplasmic antibody (ANCA) associated vasculitis, but ANCA negativity is common and more frequently encountered in EGPA with myocardial involvement. Long-term survival has substantially improved with corticosteroid treatment but myocardial involvement is still the leading cause of death in EGPA.Case presentation
A 53-year old man with a history of asthma and nasal polyposis presented with acute chest pain and elevated troponin; a percutaneous coronary intervention was performed. The left ventricle was described as hypertrophic. After 20 days the myocardium had markedly increased in thickness of both the right and left ventricle. Evaluation revealed hypereosinophilia in the blood and nasal mucosal tissue, which confirmed the diagnosis of EGPA. He presented with signs of active vasculitis including weight loss, tiredness, intracerebral hemorrhage, and increasing serum creatinine. After 6 days of corticosteroid treatment, the myocardium returned to its initial thickness.Conclusion
Rapid and marked thickening of the myocardium is not frequently reported but may occur in EGPA. Myocardial thickening in EGPA can be quickly reversed by corticosteroids, and is most likely caused by edema.238.
Food in general has a high nutrient content, which essentially passes through the human organism and ends up in the sewage system. This high nutrient content in sewage, however, is rarely included in environmental systems analyses of food products or production systems. At the same time, several studies on sewage systems have shown the significance of plant nutrients in sewage system outlets. This means that important environmental effects may be neglected in environmental systems studies of food.
We present a method for including emissions that occur after food consumption in environmental systems analyses of foods. The method uses easily accessible input data to calculate the postconsumption emissions caused by certain food products.
The method was tested by completing the results for eutrophication from seven life-cycle assessments (LCAs) on food products with the corresponding emissions caused by outlets from a sewage plant. The results showed that postconsumption eutrophication was a significant part of the products' total life-cycle impact, ranging from 5.5% (beef) to 86% (apples).
The conclusion is that including postconsumption emissions is important for studies aiming at mapping a product's life cycle to find the most environmentally relevant parts, as well as for eco-labeling purposes. If the purpose of the study is decision support, the postconsumption phase should be included where the decision affects this part of the system, otherwise not. When products are compared, postconsumption emissions should be included if their nutrient contents differ. 相似文献
We present a method for including emissions that occur after food consumption in environmental systems analyses of foods. The method uses easily accessible input data to calculate the postconsumption emissions caused by certain food products.
The method was tested by completing the results for eutrophication from seven life-cycle assessments (LCAs) on food products with the corresponding emissions caused by outlets from a sewage plant. The results showed that postconsumption eutrophication was a significant part of the products' total life-cycle impact, ranging from 5.5% (beef) to 86% (apples).
The conclusion is that including postconsumption emissions is important for studies aiming at mapping a product's life cycle to find the most environmentally relevant parts, as well as for eco-labeling purposes. If the purpose of the study is decision support, the postconsumption phase should be included where the decision affects this part of the system, otherwise not. When products are compared, postconsumption emissions should be included if their nutrient contents differ. 相似文献
239.
Gete Hestvik Monika Zahler-Rinder Dolores Gavier-Widén Ronny Lindberg Roland Mattsson David Morrison Set Bornstein 《Acta veterinaria Scandinavica》2007,49(1):21
Background
During the past decade, Chorioptes mites occupying the outer ear canals have been a common finding at routine necropsies of moose (Alces alces) in Sweden, but neither the taxonomy of the mites nor lesions from the infestation have been investigated. In this study, the mites are characterized by morphological and molecular techniques, and the histopathology of the skin of the outer ear canal is described. 相似文献240.