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11.
The fecal and mucosal microbiota of infants with rectal bleeding and the fecal microbiota of healthy age-matched controls were investigated by fluorescent in situ hybridization. Bifidobacteria were the main genus in both the feces and mucosa. The other genera tested, Bacteroides, Clostridium, Escherichia coli and lactobacilli/enterococci, represented only minor constituents. No differences in fecal microbiota were observed between patients and controls. In the patients, however, four times greater numbers of bifidobacteria were observed in the feces when compared to the mucosa. Notwithstanding this difference, a strong positive correlation prevailed for bifidobacteria in feces and mucosal samples. The genera assessed accounted for 16% of total bacterial counts on mucosal samples and for 47% of total bacterial counts in feces. This indicates that the unidentified part of the microbiota, especially on the mucosa, deserves more attention. 相似文献
12.
Laivuori H Lahermo P Ollikainen V Widen E Häivä-Mällinen L Sundström H Laitinen T Kaaja R Ylikorkala O Kere J 《American journal of human genetics》2003,72(1):168-177
Preeclampsia is a common, pregnancy-specific disorder characterized by reduced placental perfusion, endothelial dysfunction, elevated blood pressure, and proteinuria. The pathogenesis of this heterogeneous disorder is incompletely understood, but it has a familial component, which suggests that one or more common alleles may act as susceptibility genes. We hypothesized that, in a founder population, the genetic background of preeclampsia might also show reduced heterogeneity, and we have performed a genomewide scan in 15 multiplex families recruited predominantly in the Kainuu province in central eastern Finland. We found two loci that exceeded the threshold for significant linkage: chromosome 2p25, near marker D2S168 (nonparametric linkage [NPL] score 3.77; P=.000761) at 21.70 cM, and 9p13, near marker D9S169 (NPL score 3.74; P=.000821) at 38.90 cM. In addition, there was a locus showing suggestive linkage at chromosome 4q32 between D4S413 and D4S3046 (NPL score 3.13; P=.003238) at 163.00 cM. In the present study the susceptibility locus on chromosome 2p25 is clearly different (21.70 cM) from the locus at 2p12 found in an Icelandic study (94.05 cM) and the locus at 2q23 (144.7 cM) found in an Australian/New Zealand study. The locus at 9p13 has been shown to be a candidate region for type 2 diabetes in two recently published genomewide scans from Finland and China. The regions on chromosomes 2p25 and 9p13 may harbor susceptibility genes for preeclampsia. 相似文献
13.
Androgen receptor CAG polymorphism and prostate cancer risk 总被引:4,自引:0,他引:4
Mononen N Ikonen T Autio V Rökman A Matikainen MP Tammela TL Kallioniemi OP Koivisto PA Schleutker J 《Human genetics》2002,111(2):166-171
Recent studies have suggested that polymorphisms of the androgen receptor gene ( AR) may influence the risk of prostate cancer (PC) development and progression. Here, we analyzed the length of the CAG repeat of the AR gene in 1363 individuals, including patients with PC, benign prostate hyperplasia (BPH), and population controls. There was a tendency for short CAG repeats to be associated with PC. The Odds Ratio (OR) for PC was 1.47 ( P=0.05) when individuals with short CAG repeats (=18) were compared with those having long repeats (>18). CAG repeat length was not significantly associated with family history, disease stage, grade, age at diagnosis, prostate-specific antigen (PSA) level at diagnosis, or prognosis of the patients. Unexpectedly, short CAG repeats were significantly less common in patients with BPH compared with controls (OR=0.47, P=0.03). Our results suggest that the CAG polymorphism of the AR gene is unlikely to have a major role in the development or progression of PC in the Finnish population. The association of CAG repeats with the risk of BPH warrants further study. 相似文献
14.
Pirjo Kuronen Pirkko Volin Tarja Laitalainen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,718(2):781
A multisteroid screening method has been developed based on the use of 1-[4-(2,3-dihydroxypropoxy)phenyl]-1-alkanones as retention index standards and UV absorbance spectra recorded on-line with a diode-array detector using reversed-phase high-performance liquid chromatographic gradient elution with acetonitrile and water. The effect of chromatographic conditions on retention indices of steroids were studied. The method was tentatively applied to profiling of steroids in serum samples. 相似文献
15.
Using the ecosystem services approach for better planning and conservation of urban green spaces: a Finland case study 总被引:6,自引:0,他引:6
Jari Niemelä Sanna-Riikka Saarela Tarja Söderman Leena Kopperoinen Vesa Yli-Pelkonen Seija Väre D. Johan Kotze 《Biodiversity and Conservation》2010,19(11):3225-3243
Ecosystem services are vital for humans in urban regions. However, urban development poses a great risk for the ability of
ecosystems to provide these services. In this paper we first address the most important ecosystem services in functional urban
regions in Finland. Well accessible and good quality recreational ecosystem services, for example, provided by urban nature,
are an important part of a high-quality living environment and important for public health. Vegetation of urban regions can
have a role in carbon dioxide sequestration and thus in climate change mitigation. For instance, estimates of carbon sinks
can be compared to total CO2 emissions of an urban region, and the municipality can aim at both increasing carbon sinks and decreasing CO2 emissions with proper land-use planning. Large and contiguous core nature areas, smaller green areas and ecological connections
between them are the essence of regional ecological networks and are essential for maintaining interconnected habitats for
species and thus biological diversity. Thus, both local and regional level ecological networks are vital for maintaining ecosystem
services in urban regions. The impacts of climate change coupled with land-use and land cover change will bring serious challenges
for maintaining ecosystem services in urban areas. Although not yet widely used in planning practices, the ecosystem services
approach can provide an opportunity for land-use planning to develop ecologically sustainable urban regions. Currently, information
on ecosystem services of urban regions is lacking and there is a need to improve the knowledge base for land-use planning. 相似文献
16.
Tarja Lehto Pedro J. Aphalo Pekka Saranpää Tapio Laakso Aino Smolander 《Plant and Soil》2010,330(1-2):225-238
Adequate boron (B) nutrition may decrease concentrations of phenolic compounds and enhance structural integrity and lignification in plants, compared with suboptimal B. This could affect decomposition in areas where B deficiencies are common. The mass loss and changes in element concentrations in Norway spruce needle litter were studied with combinations of litter from high-B and low-B trees, incubated for 29 months, in either B fertilised or control plots without B addition. The litter originated from the same Norway spruce field experiments. Additionally, the field experiments included long-term N and P treatments. Initially, lowest lignin concentrations were found in Norway spruce litter from the treatment P and particularly in the combination B?+?P, and highest in the B?+?N fertilised plots. The mass loss of Norway spruce litter was not affected by the treatments. However, Blitter increased Cu accumulation. The litter from the B?+?P fertilised plots accumulated considerably more Al, Ca, S and Zn than the other treatments, whereas B together with N reduced the remaining amounts of these elements. Reduced nutrient release from litter may have far-reaching consequences on nutrient cycles in forests. 相似文献
17.
Pitkänen T Paakkari P Miettinen IT Heinonen-Tanski H Paulin L Hänninen ML 《Journal of microbiological methods》2007,68(3):522-529
In this work alternative media for detection and enumeration of E. coli and coliform bacteria were compared to the reference method ISO 9308-1 (LTTC) using non-disinfected water samples with background flora. The alternative media included LES Endo agar medium (LES Endo), Colilert-18 with 51-well Quanti-tray (Colilert), Chromocult Coliform agar (CC), Harlequin E. coli/Coliform medium (HECM) and Chromogenic Escherichia coli/Coliform medium (CECM). A total of 110 samples of groundwater, bathing water and spiked water was used. Our results revealed that confirmation of coliform bacteria counts is necessary, not only on lactose-based LTTC and LES Endo media, but also on the chromogenic agar media tested, due to the growth of oxidase positive colonies. LTTC and CC media also allowed the growth of some morphologically typical coliform colonies containing gram-positive bacteria. The recovery of coliform bacteria was lower on LES Endo than on LTTC. In most cases Colilert, CC, HECM and CECM gave higher coliform counts than LTTC. The use of the LTTC medium led to higher E. coli counts than obtained with any of the alternative mediums. There are three explanations for this: (1) high sensitivity of LTTC, (2) false positives on LTTC or (3) false negatives especially with Colilert, but also with chromogenic agar media. Although LTTC was found to be a very sensitive medium, the high degree of background growth of non-disinfected waters disturbed substantially the use of it. In conclusion, our results suggest that Colilert, CC and CECM are potential alternative media for detection of coliform bacteria and E. coli from non-disinfected water. 相似文献
18.
Lotta L. E. Koskinen Eija H. Sepp?l? Janelle M. Belanger Meharji Arumilli Osmo Hakosalo P?ivi Jokinen Elisa M. Nevalainen Ranno Viitmaa Tarja S. Jokinen Anita M. Oberbauer Hannes Lohi 《BMC genomics》2015,16(1)
Background
Idiopathic epilepsy is a common neurological disease in human and domestic dogs but relatively few risk genes have been identified to date. The seizure characteristics, including focal and generalised seizures, are similar between the two species, with gene discovery facilitated by the reduced genetic heterogeneity of purebred dogs. We have recently identified a risk locus for idiopathic epilepsy in the Belgian Shepherd breed on a 4.4 megabase region on CFA37.Results
We have expanded a previous study replicating the association with a combined analysis of 157 cases and 179 controls in three additional breeds: Schipperke, Finnish Spitz and Beagle (pc = 2.9e–07, pGWAS = 1.74E-02). A targeted resequencing of the 4.4 megabase region in twelve Belgian Shepherd cases and twelve controls with opposite haplotypes identified 37 case-specific variants within the ADAM23 gene. Twenty-seven variants were validated in 285 cases and 355 controls from four breeds, resulting in a strong replication of the ADAM23 locus (praw = 2.76e–15) and the identification of a common 28 kb-risk haplotype in all four breeds. Risk haplotype was present in frequencies of 0.49–0.7 in the breeds, suggesting that ADAM23 is a low penetrance risk gene for canine epilepsy.Conclusions
These results implicate ADAM23 in common canine idiopathic epilepsy, although the causative variant remains yet to be identified. ADAM23 plays a role in synaptic transmission and interacts with known epilepsy genes, LGI1 and LGI2, and should be considered as a candidate gene for human epilepsies.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1651-9) contains supplementary material, which is available to authorized users. 相似文献19.
Fungi are usually thought not to have a boron (B) requirement. It is not known if mycorrhizas take up B from low concentrations
that are common in forest soils, as fungi might also immobilise B. Here, we studied the B concentrations in sporophores of
49 ectomycorrhizal and 10 saprotrophic fungi to assess whether B is translocated in mycelium or not. Additionally, P and metal
concentrations were measured for comparison. Variability both within species and between species was very large, as the lowest
measured B concentration was 0.01 mg kg−1 in Amanita muscaria, and the highest was 280 mg kg−1 in Paxillus involutus. There was no clear difference between saprotrophic and mycorrhizal fungi. The majority of species did not accumulate B at
more than 0.01–3 mg kg−1, but there were some species that consistently had median concentration values higher than 5–6 mg kg−1 and much higher maximum values, particularly Paxillus involutus, Lactarius necator and several Russula species. Most species increased their B concentration in B fertilised plots, but there were exceptions, particularly Rozites caperatus and Lactarius camphoratus. Boron concentrations did not correlate with those of other elements. In conclusion, B is translocated in the mycelia of most
of the studied species. The differences between species may be due to differences in their water use, or carbohydrates used
in translocation. It remains to be studied, if B concentrations in mycorrhizas or mycelia in soil are in the same order of
magnitude as the larger ones found here, and if this has any effects on the host plants. 相似文献
20.
Different metabolic responses of human brown adipose tissue to activation by cold and insulin 总被引:1,自引:0,他引:1
Orava J Nuutila P Lidell ME Oikonen V Noponen T Viljanen T Scheinin M Taittonen M Niemi T Enerbäck S Virtanen KA 《Cell metabolism》2011,14(2):272-279
We investigated the metabolism of human brown adipose tissue (BAT) in healthy subjects by determining its cold-induced and insulin-stimulated glucose uptake and blood flow (perfusion) using positron emission tomography (PET) combined with computed tomography (CT). Second, we assessed gene expression in human BAT and white adipose tissue (WAT). Glucose uptake was induced 12-fold in BAT by cold, accompanied by doubling of perfusion. We found a positive association between whole-body energy expenditure and BAT perfusion. Insulin enhanced glucose uptake 5-fold in BAT independently of its perfusion, while the effect on WAT was weaker. The gene expression level of insulin-sensitive glucose transporter GLUT4 was also higher in BAT as compared to WAT. In conclusion, BAT appears to be differently activated by insulin and cold; in response to insulin, BAT displays high glucose uptake without increased perfusion, but when activated by cold, it dissipates energy in a perfusion-dependent manner. 相似文献