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101.
BackgroundIncreased red cell distribution width (RDW) has been related to poor prognosis in patients with cardiovascular disease, and is a predictor of cardiovascular mortality in the general population. The purpose of the present study was to investigate if RDW is associated with increased incidence of stroke and its subtypes in individuals from the general population.MethodsRed cell distribution width was measured in 26,879 participants (16,561 women and 10,318 men aged 45–73 years) without history of coronary events or stroke, from the population-based Malmö Diet and Cancer Study. Incidences of total stroke and stroke subtypes over a mean follow-up of 15.2 years were calculated in relation to sex-specific quartiles of RDW. The presence of carotid plaque and intima–media thickness, as assessed by ultrasound, was studied in relation to RDW in a randomly selected subcohort (n = 5,309).ResultsIncidences of total stroke (n = 1,869) and cerebral infarction (n = 1,544) were both increased in individuals with high RDW. Hazard ratios (HRs) in the highest compared to the lowest quartile were 1.31 for total stroke (95% confidence interval [CI]: 1.11–1.54, p for trend = 0.004) and 1.32 for cerebral infarction (95% CI: 1.10–1.58, p for trend = 0.004) after adjustment for stroke risk factors and hematological parameters. The adjusted HR for intracerebral hemorrhage (n = 230) was 1.44 (95% CI: 0.90–2.30) and the HR for subarachnoid hemorrhage (n = 75) was 0.94 (95% CI: 0.43–2.07), in the highest compared to the lowest quartile of RDW. Red cell distribution width was positively associated with intima–media thickness of the common carotid artery (p for trend = 0.011).ConclusionsRed cell distribution width in the highest quartile was associated with increased incidence of total stroke and cerebral infarction. There was no significant association between RDW and incidence of intracerebral or subarachnoid hemorrhage.  相似文献   
102.
DNA sequence variants in genes involved in the innate immune response and secondary response to infection may confer susceptibility to chronic otitis media with effusion and/or recurrent otitis media (COME/ROM). We evaluated single nucleotide polymorphisms (SNPs) in 15 functional candidate genes. A total of 99 SNPs were successfully genotyped on the Sequenom platform in 142 families (618 subjects) from the Minnesota COME/ROM Family Study. Data were analyzed for association with COME/ROM using the Generalized Disequilibrium Test (GDT). Sex and age at exam were adjusted as covariates, relatedness was accounted for, and genotype differences from all phenotypically discordant relative pairs were utilized to measure the evidence of association between COME/ROM and each SNP. SNP rs2735733 in the region of the mucin 5, subtypes A/C gene (MUC5AC) exhibited nominal evidence for association with COME/ROM (P = 0.002). Two additional SNPs from this region had P values<0.05. Other variants exhibiting associations with COME/ROM at P<0.05 included the SCN1B SNP rs8100085 (P = 0.013), SFTPD SNP rs1051246 (P = 0.039) and TLR4 SNP rs2770146 (P = 0.038). However, none of these associations replicated in an independent sample of COME/ROM families. The candidate gene variants examined do not appear to make a major contribution to COME/ROM susceptibility, despite a priori evidence from functional or animal model studies for a role in COME/ROM pathology.  相似文献   
103.
In the search for ways to combat degenerative neurological disorders, neurogenesis-stimulating factors are proving to be a promising area of research. In this study, we show that the hormonal factor prolactin (PRL) can activate a pool of latent precursor cells in the adult mouse hippocampus. Using an in vitro neurosphere assay, we found that the addition of exogenous PRL to primary adult hippocampal cells resulted in an approximate 50% increase in neurosphere number. In addition, direct infusion of PRL into the adult dentate gyrus also resulted in a significant increase in neurosphere number. Together these data indicate that exogenous PRL can increase hippocampal precursor numbers both in vitro and in vivo. Conversely, PRL null mice showed a significant reduction (approximately 80%) in the number of hippocampal-derived neurospheres. Interestingly, no deficit in precursor proliferation was observed in vivo, indicating that in this situation other niche factors can compensate for a loss in PRL. The PRL loss resulted in learning and memory deficits in the PRL null mice, as indicated by significant deficits in the standard behavioral tests requiring input from the hippocampus. This behavioral deficit was rescued by direct infusion of recombinant PRL into the hippocampus, indicating that a lack of PRL in the adult mouse hippocampus can be correlated with impaired learning and memory.  相似文献   
104.
Genotoxicity of heat-processed foods   总被引:7,自引:0,他引:7  
Jägerstad M  Skog K 《Mutation research》2005,574(1-2):156-172
Gene-environment interactions include exposure to genotoxic compounds from our diet and it is no doubt, that humans are regularly exposed to e.g. food toxicants, not least from cooked foods. This paper reviews briefly four classes of cooked food toxicants, e.g. acrylamide, heterocyclic amines, nitrosamines and polyaromatic hydrocarbons. Many of these compounds have been recognised for decades also as environmental pollutants. In addition cigarette smokers and some occupational workers are exposed to them. Their occurrence, formation, metabolic activation, genotoxicity and human cancer risk are briefly presented along with figures on estimated exposure. Several lines of evidence indicate that cooking conditions and dietary habits can contribute to human cancer risk through the ingestion of genotoxic compounds from heat-processed foods. Such compounds cause different types of DNA damage: nucleotide alterations and gross chromosomal aberrations. Most genotoxic compounds begin their action at the DNA level by forming carcinogen-DNA adducts, which result from the covalent binding of a carcinogen or part of a carcinogen to a nucleotide. The genotoxic and carcinogenic potential of these cooked food toxicants have been evaluated regularly by the International Agency for Research on Cancer (IARC), which has come to the conclusion that several of these food-borne toxicants present in cooked foods are possibly (2A) or probably (2B) carcinogenic to humans, based on both high-dose, long-term animal studies and in vitro and in vivo genotoxicity tests. Yet, there is insufficient scientific evidence that these genotoxic compounds really cause human cancer, and no limits have been set for their presence in cooked foods. However, the competent authorities in most Western countries recommend minimising their occurrence, therefore this aspect is also included in this review.  相似文献   
105.
106.
Francisella tularensis live vaccine strain infection of mice has been established as an experimental model of tularemia that is suitable for studies of immune mechanisms against the intracellular pathogen. In this study, the model was used to explore immunogenic repertoire of F. tularensis with the aim of identifying new molecules able to activate the host immune system, potential bacterial markers with vaccine, and diagnostic applications. Immunoproteomic approach based on the combination of two-dimensional gel electrophoresis, immunoblotting, and mass spectrometry was applied. Globally, 36 different proteins were identified, which strongly reacted with sera from experimentally infected mice, including several putative virulence markers of intracellular pathogens as nucleoside diphosphate kinase, isocitrate dehydrogenase, RNA-binding protein Hfq, and molecular chaperone ClpB. Of them, 27 proteins are described for the first time as immunorelevant Francisella proteins. When comparing murine immunoproteome of F. tularensis with our previous data from human patients, 25 of the total of 50 identified murine sera immunoreactive spots were recognized by human sera collected from patients suffering from tularemia, as well. Immune sera from two Lps gene congenic strains of mice, C3H/HeN (Lpsn) and C3H/HeJ (Lpsd), represented murine immunoproteome in this study. The spectrum of immunoreactive spots detected by two-dimensional immunoblotting varied throughout the course of infection depending on murine strain. Nevertheless, the antibody patterns of the two strains showed significant homogeneity in being directed against almost identical subset of antigens.  相似文献   
107.
Past and ongoing vertebrate introductions threaten to rearrange ecological communities in the Indo‐Malay Archipelago, one of Earth's most biodiverse regions. But the consequences of these translocations are difficult to predict. We compared local abundance and distributions in four tropical mammal lineages that have crossed from Asia to Wallacea or New Guinea. The local abundance of macaques (Macaca spp.), which naturally crossed Wallace's Line, was higher in Sulawesi (east of the line; mean = 3.7 individuals per camera station, 95% CI = 2.2: 5.1) than in Borneo (west of the line; mean = 1.1, CI = 0.8: 1.4), but the local abundance of Malay civets (Viverra tangalunga), Rusa deer, and Sus pigs was similar in their native ranges and where they had been introduced by humans east of Wallace's Line. Proximity to rivers increased Malay Civet local abundance and decreased the local abundance of pigs in parts of their introduced ranges (Maluku and New Guinea, respectively), while having no effect on local abundance in their native ranges (Borneo) or other areas where they have been introduced (Sulawesi). That local abundance was higher east of Wallace's Line in just one of four mammal lineages is consistent with findings from plant invasions, where most species have similar abundance in their native and introduced ranges. However, species’ ecology may change as they enter new communities, for example, their patterns of abundance at local scales. This could make it difficult to predict community structure in the face of ongoing species introductions.  相似文献   
108.
The objectives were to quantify aboveground, belowground and dead wood carbon pools near Mayoko in the Chaillu massif of Republic of Congo and explore relationships between carbon storage and plant diversity of all growth forms. A total of 190 plots (25 m by 25 m) were sampled (5072 stems, 211 species) and data analysed using recommended central-African forest allometric equations. Mean stem diameter at breast height was 33.6 cm, mean basal area 47.7 m2 ha−1 and mean density of individuals 407 ha−1. Mean aboveground carbon (AGC) ranged from 13.93–412.66 Mg C ha−1, belowground carbon from 2.86–96.97 Mg C ha−1 and dead wood from 0.00–7.59 Mg C ha−1. The maximum AGC value recorded in a plot was 916 Mg C ha−1. The analysis performed using phytosociological association as basis rather than broad vegetation type is unique. AGC values for undisturbed terra firme forest sites featured among the highest recorded for African tropical forests. Considering only tree diversity, a weak, yet significant, relationship existed between AGC and species richness, Shannon-Wiener index of diversity and Fisher's alpha. However, if diversity of all plant growth forms is considered, no relationship between carbon and plant diversity existed.  相似文献   
109.
The ultrastructure of the nervous system of a planarian, Procerodes littoralis, belonging to the taxon Maricola is described for the first time. The study has revealed the presence of two neuronal cell types and a glia-like cell. Immunogold labelling with antibodies to two native flatworm neuropeptides—neuropeptide F and GNFFRFamide—has been localised to one neuronal cell type and associated processes and synapses, thus indicating its peptidergic nature. The ultrastructural features are compared to those of other investigated turbellarian species. The number of features shared by species from the Proseriata, Lecitoepitheliata and Tridadida show that in respect of the nervous system these taxa form a closely related group.  相似文献   
110.
Characters of the nervous system have scarcely been used in consideration of the phylogenetic relationships of the Tricladida. In order to contribute characters toward this end, we studied the nervous system of Planaria torva with immunocytochemical methods and we compare the results with what is known of nervous system structure in other triclads. Antisera against four neuroactive substances were used: neuropeptide F (NPF), RFamide, GYIRFamide, and serotonin (5-HT). All four substances showed positive immunoreactions throughout the nervous system; and the patterns of distribution of the first three were similar, while 5-HT showed a distinct distribution. The organization of these nervous system elements in Planariidae and Dendrocoelidae resembles that of the Maricola but differs from that of the Dugesiidae. The results support the hypotheses that the Paludicola is a more advanced taxon than the Maricola and that the Planariidae and Dendrocoelidae together are a sister group of the Dugesiidae. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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