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1.
Longevity is a key demographic characteristic of herbaceous plants, but often unknown. While root or rhizome growth ring analysis may allow assessment plant longevity directly and conveniently, so far it has only been used in a few case studies of herbaceous dicotyledonous species. To evaluate whether growth ring analysis is applicable to a large spectrum of herbaceous dicotyledonous plant species, we used plant communities of varying species richness in a 12-year-old grassland biodiversity experiment (Jena Experiment). Cross-sections of the oldest available part of the plants were analysed for all available dicotyledonous perennial herb species (S = 37), which represented three functional groups: legumes, small herbs and tall herbs. We studied 1664 individuals representing the genet in clearly distinguishable plant individuals, and the ramet in clonally growing plant species.Roots of eleven species with permanent primary root were harvested. They showed clearly visible growth rings. Longevity was extended with a mean age of 4.0 years (SE = 0.3). Seven species, which also had a permanent primary root, showed less distinct growth rings. They were shorter-lived (mean age 3.0 years (SE = 0.3)). In six species with obligate clonal growth mostly rhizomes were sampled, but individuals were still identifiable due to their growth habit. For these species growth rings were clearly visible. Longevity of rhizomes was extended (mean age 3.3 years (SE = 0.5)). In 13 species with obligate clonal growth also rhizomes were sampled, but plant individuals were not identifiable. For these species longevity was low (mean age 2.1 years (SE = 0.2)). Community mean age was significantly lower when small herbs were present and higher when tall herbs were present, while legumes had no effect on community mean age. In summary, anatomical analysis of roots and rhizomes is a suitable tool to study the population age structure of a large spectrum of perennial dicotyledonous herbaceous species and therefore opens new perspectives for demographic studies at the community level.  相似文献   

2.
Live oak (Quercus virginiana Mill.) is a long lived, broadleaf, evergreen species native to the lower Coastal Plain of the southern and southeastern United States and is frequently planted in the urban environment. However, live oak has received limited attention for its potential for dendrochronological analyses possibly because its growth-ring boundaries may be less defined due to the absence of a distinct dormancy period. The objective of this explorative study was to determine whether live oak rings in both urban and historic trees could be accurately identified and measured for dendrochronological applications. One hundred urban live oaks were assessed as well as four cross-sectional specimens from historic sites in the southeastern United States. Age of all cored live oak ranged from 7 to 29 (average = 16.8 rings), while cross-sections were taken from trees with an average age of 175 years. A chronology was created from cores that had the highest interseries correlations (n = 27), resulting in an average interseries correlation of 0.654. The analysis of live oak cross sections revealed that the rings on live oak are very faint and barely discernible, delimited mainly by a faint row of earlywood vessels with no or barely visible terminal parenchyma. Rings on these sections were erratic (i.e., fading out along the circumference) and non-concentric (i.e., a particular ring could be both wide and narrow at certain points along the circumference) so that any attempt to measure the rings on opposing radii would have produced meaningless results. However, based on the results of this study, we conclude that the dendrochronological analysis of live oak is possible with careful sample preparation and analysis and that results would be reliable, even for urban trees. Results of this study suggest that urban tree-ring series with higher interseries correlations were more vigorous than those with lower values, suggesting that urban environmental stresses related to individual sites may decrease the usefulness of crossdating techniques for evaluating annual rings on younger, urban trees.  相似文献   

3.
The polymorphism of the mitochondrial gene cytochrome oxidase III was studied in the Mediterranean octopus, Octopus vulgaris Cuvier, 1797. A total of 202 specimens from seven sampling sites were analysed with the aim of elucidating patterns of genetic structure in the central Mediterranean Sea and to give an insight into the phylogeny of the Octopus genus. Phylogenetic analyses showed that individuals from the central Mediterranean belong to the O. vulgaris species whose limits should nevertheless be clarified. Concerning genetic structure, two high-frequency haplotypes were present in all locations. The overall genetic divergence (ΦST = 0.05, P < 0.05) indicated a significant genetic structuring in the study area and an AMOVA highlighted a significant break between western and eastern Mediterranean basins (ΦCT = 0.094, P < 0.05). Possible explanations for the observed patterns of genetic structuring are discussed with reference to their relevance for fisheries management.  相似文献   

4.
The current study evaluated 23 children (ages 2–16 years) with recurrent food intolerance and allergies for CoQ10 deficiency and mitochondrial abnormalities. Muscle biopsies were tested for CoQ10 levels, pathology, and mitochondrial respiratory chain (MRC) activities. Group 2 (age > 10 years; n = 9) subjects had significantly decreased muscle CoQ10 than Group 1 (age < 10 y; n = 14) subjects (p = 0.001) and 16 controls (p < 0.05). MRC activities were significantly lower in Group 2 than in Group 1 (p < 0.05). Muscle CoQ10 levels in study subjects were significantly correlated with duration of illness (adjusted r2 = 0.69; p = 0.012; n = 23). Children with recurrent food intolerance and allergies may acquire CoQ10 deficiency with disease progression.  相似文献   

5.
Livestock husbandry in the dry areas of the Mediterranean basin is facing scarcity and fluctuation of feed supply and feed prices. At the same time the local agro-food industry is expanding and its by-products might be used as alternatives to traditional feed resources, but their nutritional value is not well known. Therefore, four by-products typical for the Mediterranean area were tested in vitro (n = 3 per diet or feed), in sacco (n = 6) and in vivo (n = 6) either individually or in a proportion of 0.34 of the total diet. The test feeds (broken lentils, sugar beet pulp, tomato pomace and crude olive cake) were compared to a barley–wheat bran mixture (control). Forage (barley straw) made up proportionately 0.5 of the diet. For all experiments either rumen canulated or intact castrated male Awassi sheep were employed. The thirty sheep used in the in vivo experiment weighed on average 42 kg. The animals were fed 1.1 kg dry matter (DM)/day and had free access to water. Large compositional differences (g/kg DM) between the batches of test feeds used in the present study were found in crude protein (from 79 to 245; for olive cake and broken lentils), neutral detergent fiber (aNDFom; from 283 to 584; for broken lentils and olive cake) and non-fiber carbohydrates (from 109 to 436 for tomato pomace and olive cake and to broken lentils). Two feeds (tomato pomace and olive cake) were rich in ether extract; sugar beet pulp was rich in calcium. Broken lentils had the highest effective degradabilities (ED). Olive cake was lowest in ED of OM and aNDFom (0.39 and 0.32, respectively). Olive cake caused refusals of concentrate (lower proportionate concentrate intake compared with the control, P<0.001). The apparent nutrient digestibility of broken lentils and sugar beet pulp was similar (P<0.001) to the control and lower (P<0.001) for tomato pomace and olive cake. Metabolizable energy (ME; MJ/kg DM) was determined by various ways and always showed a very low value for olive cake (1–2). Broken lentils and sugar beet pulp had ME contents higher (P<0.001) than that of tomato pomace. The study showed that some by-products were promising as alternatives to traditional concentrate ingredients, while others, especially olive cake, might be only used at low levels.  相似文献   

6.
Telomeres progressively shorten with repeated somatic tissue cell division, their length being an indicator of cellular ageing. Telomeric dysfunction may be implicated in a variety of diseases. We measured mean telomere length in peripheral blood leukocytes (PBL) from patients with various rheumatologic diseases. Mean PBL telomere length was measured using real-time quantitative polymerase chain reaction (Q-PCR) assay in a control population (n = 130; age range: 3–94 years) and in subjects diagnosed with rheumatoid arthritis (RA; n = 86; age range: 31–82 years), psoriatic arthritis (PA; n = 56; age range: 26–79 years) and ankylosing spondylitis (AS; n = 59; age range: 21–75 years). These diseases are associated with chronic systemic inflammatory activity. Telomere length was also quantified in subjects with osteoarthritis (OA; n = 34; age range: 43–82 years) and osteoporosis (OP; n = 35; age range: 59–95 years), diseases without a chronic systemic inflammatory component. Telomere length in OA showed no differences from age-matched controls (p = 0.234), but was significantly shorter in OP (p = 0.001). Telomere length was significantly longer than controls in RA (p = 0.015), PA (p < 0.001) and AS (p < 0.001). Different patterns in telomere length from PBL are evidenced in rheumatologic pathologies, possibly dependent on the presence or absence of chronic systemic inflammation.  相似文献   

7.
PurposeThe aim of this study was to investigate the influence of the TNF -308 G/A polymorphism in the promoter region of the tumor necrosis factor-α gene on the susceptibility and severity of rheumatoid arthritis (RA) in individuals from the Brazilian Amazon.MethodsA total of 323 individuals—192 healthy controls without arthritis and 131 individuals suffering from arthritis—were genotyped for this polymorphism using a methodology based on PCR-RFLP.ResultsThe frequency of the A allele (TNF2) in rheumatoid arthritis sufferers was not significantly higher than in the controls (p = 0.926; OR = 0.97; confidence interval 0.54–1.76). However, using a logistic regression model, when the patients were stratified according to whether the manifestations were preponderantly articular or systemic, there was a strong association between the TNF2 allele and systemic arthritis (p = 0.001; OR = 5.89; confidence interval = 1.98–17.5) as well as the use of anti-TNF immunotherapy (p = 0.023; OR = 1.10; confidence interval = 1.00–1.14). The main factors that were found to influence the risk of extra-articular disease were age greater than or equal to 60 years (p = 0.008; OR = 4.06; confidence interval = 1.45–11.38), disease duration greater than 10 years (p = 0.031; OR = 3.10; confidence interval = 1.11–8.63) and positive rheumatoid factor (p = 0.035; OR = 2.07; confidence interval = 1.05–4.09).ConclusionsThese results suggest that the TNF2 allele is associated with the more serious forms of the disease in individuals from the Brazilian Amazon but not with a risk for developing RA.  相似文献   

8.
《Dendrochronologia》2014,32(4):336-342
We used dendroarchaeological techniques to determine the year of construction of two historic structures in the Valles Caldera National Preserve of New Mexico, USA. Historical documents date some structures in the headquarters area of the Preserve, but the Commissary Cabin and Salt Barn were lacking conclusive construction dates. Both structures were originally thought to have been built by the Otero family who bought the property in 1899. We found that the structures were built from two tree species, white fir (Abies concolor (Gordon) Lindl. ex Hildebr.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), surprising given that ponderosa pines are also found in great numbers in the adjacent forest. Tree rings from 20 logs were confidently crossdated both graphically and statistically and provided cutting dates of trees in both structures of 1940 and 1941 when compared against the Fenton Lake reference chronology (Commissary Cabin: r = 0.69, t = 15.54, p < 0.0001, n = 263 years; Salt Barn: r = 0.77, t = 11.7, p < 0.0001, n = 232 years). By combining the cutting date years and terminal ring attributes, we suggest that both structures were built in the spring or early summer of 1941 using freshly cut logs and logs that had been cut the previous spring (1940, before or during the growing season) and stockpiled. The cutting dates of 1940 and 1941 indicate that these buildings were constructed during the Franklin Bond (1939–1945) era and associated with the transition from sheep ranching to more modern cattle grazing. These new dates provide a more distinct understanding of the cultural resources at the Valles Caldera National Preserve and provide interpretative staff with more accurate information that can be given to the public.  相似文献   

9.
The first trees in New York were Middle Devonian (earliest Givetian) cladoxyls (?Duisbergia and Wattieza), with shallow-rooted manoxylic trunks. Cladoxyl trees in New York thus postdate their latest Emsian evolution in Spitzbergen. Progymnosperm trees (?Svalbardia and Callixylon–Archaeopteris) appeared in New York later (mid-Givetian) than progymnosperm trees from Spitzbergen (early Givetian). Associated paleosols are evidence that Wattieza formed intertidal to estuarine mangal and Callixylon formed dry riparian woodland. Also from paleosols comes evidence that Wattieza and Callixylon required about 350 mm more mean annual precipitation than plants of equivalent stature today, that Wattieza tolerated mean annual temperature 7 °C less than current limits of mangal (20 °C), and Callixylon could tolerate temperatures 14 °C less than modern mangal. Devonian mangal and riparian woodland spread into New York from wetter regions elsewhere during transient paleoclimatic spikes of very high CO2 (3923 ± 238 ppmv), and subhumid (mean annual precipitation 730 ± 147 mm) conditions, which were more likely extrinsic atmospheric perturbations rather than consequences of tree evolution. For most of the Middle Devonian CO2 was lower (2263 ± 238 ppmv), and paleoclimate in New York was semiarid (mean annual precipitation 484 ± 147 mm). Such transient perturbations and immigration events may explain the 40 million year gap between the late Emsian (400 Ma) evolution of trees and Famennian (360 Ma) CO2 drawdown and expansion of ice caps.  相似文献   

10.
The importance of the spatial organisation of individuals in explaining species coexistence within a community is widely recognised. However, few analyses of spatial structure have been performed on tropical agroforests.The main objective of this study was to highlight the links between spatial organisation of shade trees on the one hand, and shade tree species richness and cacao yield on the other, using data from 29 cacao agroforests in Costa Rica.A method of spatial statistics, Ripley's K-function, was used to analyse the spatial organisation of shade and cacao trees in the study plots. For each stand, the X and Y coordinates of ≥2.5-m-tall trees were recorded. In each plot we also assessed shade tree species richness and cacao yield (with total number of pods = number of pods damaged by frosty pod rot + number of healthy pods).Three types of stands were identified: the first was characterised by significant clustering of shade trees, the highest shade tree species richness (S = 6), and the highest number of damaged pods (139 pods ha?1 year?1). The second type was characterised by random spatial organisation of shade trees. The third type showed a trend towards regular organisation. Species richness of shade trees did not differ significantly between the last two types (S = 4 for both), nor did the number of damaged pods (56 pods ha?1 year?1 and 67 pods ha?1 year?1 respectively).Although the trends were not statistically significant for all the variables in our data set, the clustered spatial structure appears to favour a synergy between environmental (tree species richness), and provisioning (cacao production) services.  相似文献   

11.
Aims. We conducted a large registry-based study in California to investigate the association of perinatal factors and childhood leukemia with analysis of two major subtypes, acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML). Methods. We linked California cancer and birth registries to obtain information on 5788 cases and 5788 controls matched on age and sex (1:1). We examined the association of birth weight, gestational age, birth and pregnancy order, parental ages, and specific conditions during pregnancy and risk of total leukemia, ALL and AML using conditional logistic regression, with adjustment for potential confounders. Results. The odds ratio (OR) per 1000 g increase in birth weight was 1.11 for both total leukemia and ALL. The OR were highest for babies weighing ≥4500 g with reference <2500 g: 1.59 (95% CI: 1.05–2.40) and 1.70 (95% CI: 1.08–2.68) for total leukemia and ALL, respectively. For AML, increase in risk was also observed but the estimate was imprecise due to small numbers. Compared to average-for-gestational age (AGA), large-for-gestational age (LGA) babies were at slightly increased risk of total childhood leukemia (OR = 1.10) and both ALL and AML (OR = 1.07 and OR = 1.13, respectively) but estimates were imprecise. Being small-for-gestational age (SGA) was associated with reduced risk of childhood leukemia (OR = 0.81, 95% CI: 0.67–0.97) and ALL (OR = 0.77, 95% CI: 0.63–0.94), but not AML. Being first-born was associated with decreased risk of AML only (OR = 0.70; 95% CI: 0.53–0.93). Compared to children with paternal age <25 years, children with paternal age between 35 and 45 years were at increased risk of total childhood leukemia (OR = 1.12; 95% CI: 1.04–1.40) and ALL (OR = 1.23; 95% CI: 1.04–1.47). None of conditions during pregnancy examined or maternal age were associated with increased risk of childhood leukemia or its subtypes. Conclusions. Our results suggest that high birth weight and LGA were associated with increased risk and SGA with decreased risk of total childhood leukemia and ALL, being first-born was associated with decreased risk of AML, and advanced paternal age was associated with increased risk of ALL. These findings suggest that associations of childhood leukemia and perinatal factors depend highly on subtype of leukemia.  相似文献   

12.
DNA and chromosome damages in peripheral blood lymphocytes were evaluated in 151 workers occupationally exposed to formaldehyde (FA) and 112 non-FA exposed controls. The effects of polymorphisms in three glutathione-S-transferase (GSTs) genes on the DNA and chromosome damages were assessed as well. Alkaline comet assay and cytokinesis-block micronucleus (CBMN) assay were used to determine DNA and chromosome damages, respectively. The genotypes of GSTP1 (Ile105Val), GSTT1, and GSTM1 were assayed. The mean 8-h time-weighted average (TWA) concentrations of FA in two plywood factories were 0.83 ppm (range: 0.08–6.30 ppm). FA-exposed workers had higher olive tail moment (TM) and CBMN frequency compared with controls (Olive TM, 3.54, 95%CI = 3.19–3.93 vs. 0.93, 95%CI = 0.78–1.10, P < 0.01; CBMN frequency, 5.51 ± 3.37 vs. 2.67 ± 1.32, P < 0.01). Olive TM and the CBMN frequency also had a dose-dependent relation with the personal FA exposure. Significant association between FA exposure history and olive TM and CBMN frequency were also identified. The level of olive TM was slightly higher in FA-exposed workers with GSTM1 null genotype than those with non-null genotype (3.86, 95%CI = 3.31–4.50 vs. 3.27, 95%CI = 2.83–3.78, P = 0.07) with adjustment of covariates. We also found that FA-exposed workers carrying GSTP1 Val allele had a slightly higher CBMN frequency compared with workers carrying only the wild-type allele (6.32 ± 3.78 vs. 5.01 ± 2.98, P = 0.05). Our results suggest that the FA exposure in this occupational population increased DNA and chromosome damages and polymorphisms in GSTs genes may modulate the genotoxic effects of FA exposure.  相似文献   

13.
In Florida, a root weevil pest of citrus, Diaprepes abbreviatus, is more damaging and attains higher population density in some orchards on fine textured, poorly drained “flatwoods” soils than in those on the deep, coarse sandy soils of the central ridge. Previous research revealed that sentinel weevil larvae were killed by indigenous entomopathogenic nematodes (EPNs) at significantly higher rates in an orchard on the central ridge, compared to one in the flatwoods. We hypothesized that filling tree planting holes in a flatwoods orchard with sandy soil from the central ridge would provide a more suitable habitat for EPNs, thereby reducing weevil numbers and root herbivory. Fifty trees were planted in oversized planting holes filled with coarse sand and 50 trees were planted in native soil in a split plot design where whole plots were species of introduced EPNs and split plots were soil type. Each of Steinernema diaprepesi, Steinernema riobrave, Heterorhabditis indica, Heterorhabditis zealandica, or no EPNs were introduced into the rhizospheres in 10 plots of each soil type. During four years, EPN numbers in soil samples and the relative abundance of seven species of nematophagous fungi associated with nematodes were measured three times using real-time PCR. The efficacy of EPNs against sentinel weevil larvae was also measured three times by burying caged weevils in situ. EPN species richness (P = 0.001) and diversity (P = 0.01) were always higher in sand than native soil. Soil type had no effect on numbers of EPNs in samples, but EPNs were detected more frequently (P = 0.01) in plots of sandy soil than native soil in 2011. Two nematophagous fungi species, Paecilomyces lilacinus and Catenaria sp. were significantly more abundant in nematode samples from sandy soil on all three sampling dates. Efficacy of EPNs against weevil larvae was greater in sandy soil inoculated with S. diaprepesi (P = 0.03) in June 2010 and in all treatments in sandy soil in May 2011 (P = 0.03). Sixty-eight percent more adult weevils (P = 0.01) were trapped emerging from native soil during two years than from sandy soil. By May 2011, the cumulative number of weevils emerging from each plot was inversely related (P = 0.01) to the numbers of EPNs detected in plots and to EPN efficacy against sentinels. Three trees in sandy soil died as a result of root herbivory compared to 21 trees in native soil. Surviving trees in sandy soil had trunk diameters that were 60% larger (P = 0.001) and produced 85% more fruit (P = 0.001) than those in native soil. Although it is not possible to characterize all of the mechanisms by which the two soil treatments affected weevils and trees, substitution of sand for native soil was an effective means of conserving EPNs and shows promise as a cultural practice to manage D. abbreviatus in flatwoods citrus orchards with a history of weevil damage to trees.  相似文献   

14.
This study investigates Pb isotope ratios at low concentrations (parts per billion; ppb) in tree rings and soils in the Northern Athabasca Oil Sands Region (NAOSR), western Canada, to evaluate if: (1) climatic conditions influence on tree-ring Pb assimilation; and (2) such low Pb content allows inferring the regional Pb depositional history.Our results reflect the influence of winter snow cover and the importance of minimum temperature and precipitation in spring and summer on the bioavailability of Pb and its passive assimilation by trees in sub-arctic semi-humid climatic conditions. Winter conditions can influence the state of root systems that subsequently impacts the following growth period, while spring and summer conditions likely control microbial processes and water source, and may thus impact Pb assimilation by trees. Thus, the results of tree-ring Pb concentrations show interesting correlation with cumulated snow from November of the previous year to February (ρ = 0.53; P < 0.01; n = 36). Likewise, the 206Pb/207Pb ratios inversely correlate with minimum temperature from April to September (ρ = −0.67; P < 0.01; n = 40) and precipitation from May to August (ρ = −0.42; P < 0.01; n = 36). The isotopic results also suggest that the effects of climatic variations are superimposed by regional industrial Pb deposition: Western North American Aerosols (WNAA) and fugitive dust from the oil sands mining operations appear to be the most likely sources.Importantly, this study suggests that even at low Pb concentrations, tree-ring Pb isotopes are modulated by climatic conditions and potential input of regional and long-range transport of airborne Pb. These interpretations open the possibility of using Pb isotopes as an environmental tool for inferring the pollution history in remote regions, and improving our understanding of its natural cycle through the forest environment.  相似文献   

15.
An in vitro dose–response curve following exposure to γ-radiation was determined at the IST/ITN, by use of the chromosomal aberration assay. This is the first study of this kind carried out among the Portuguese population. Un-irradiated and γ-irradiated peripheral blood lymphocytes from 16 healthy donors were cultured. A total of 22,395 metaphases were analyzed for frequency and distribution of dicentrics and centric rings, as a function of the radiation dose. The dose–response data for dicentrics and dicentrics plus centric rings were fitted by use of a linear–quadratic model: Ydic = (0.0011 ± 0.0006) + (0.0105 ± 0.0035)D + (0.0480 ± 0.0019)D2 and Ydic + rings = (0.0011 ± 0.0006) + (0.0095 ± 0.0036)D + (0.0536 ± 0.0020)D2. Also, calibration curves related to age and gender were determined, but no significant differences were found. Following the establishment of the dose–response curves, a validation experiment was carried out with three individuals. Real and estimated doses, obtained with the dose–response curves, were in agreement. These results give us confidence to apply both dose–response calibration curves in future biological dosimetry requirements.  相似文献   

16.
The Valdavara-1 cave, located in the westernmost part of the Iberian Peninsula, is an archaeological site that has been excavated since 2007. At least two main sedimentary units have been identified: an upper one, 30 cm-thick, that has yielded many fragments of ceramic characteristic of the Recent Prehistory (with a radiocarbon age of 4.490 ± 40 years BP), and a lower one, 90 cm-thick, separated from the upper one by an erosive discontinuity and late Pleistocene in age (radiocarbon ages between 13.770 ± 70 and 15.120 ± 70 years BP). The small-vertebrate assemblages recovered from the sieving-washing of all the sediment from the excavation campaigns include a total of at least 34 taxa (six amphibians, nine squamate reptiles, five insectivores, two chiropterans and 12 rodents). The materials from this locality constitutes the first mention in northwestern Spain for Microtus (Iberomys) cabrerae and Micromys minutus, currently absent from this area, as well as the first mention in the fossil record for Chioglossa lusitanica, Discoglossus galganoi and Chalcides striatus. In both layers, such small-vertebrate associations suggest a patchy landscape dominated by humid meadows and woodland areas, with the existence of water areas in the vicinity of the cave. The climate shows a more continental pattern during the late Pleistocene, as evidenced by the presence of Microtus arvalis, Sorex minutus and Rana temporaria, and was milder during the Recent Prehistory, with the occurrence of typically Mediterranean taxa such as Crocidura russula, Chioglossa lusitanica, Discoglossus galganoi, Rana iberica, Chalcides striatus and Timon lepidus. The amphibian and squamate associations suggest that the climate change recorded at the Valdavara-1 cave between the latest Pleistocene and Holocene levels may correspond to a difference of 0.8 °C in terms of mean annual temperature, although the difference is 2.8 °C for the mean temperature of the coldest month.  相似文献   

17.
ObjectiveTo determine the serum levels of Th1 (IL-12, IFN-γ,TNF-α) and Th2 (IL-5, IL-6 and IL-10) cytokines in childhood-onset SLE, first-degree relatives and healthy controls. To elucidate their association with disease activity, laboratory and treatment features.MethodsWe included 60 consecutive childhood-onset SLE patients [median age 18 years (range 10–37)], 64 first-degree relatives [median 40 (range 28–52)] and 57 healthy [median age 19 years (range 6–30 years)] controls. Controls were age and sex-matched to SLE patients. SLE patients were assessed for clinical and laboratory SLE manifestations, disease activity (SLEDAI), damage (SDI) and current drug exposures. Mood and anxiety disorders were determined through Becks Depression (BDI) and Anxiety Inventory (BAI). Th1 (IL-12, IFN-γ,TNF-α) and Th2 (IL-5, IL-6 and IL-10) cytokines levels were measured by ELISA and compared by non-parametric tests.ResultsSerum TNF-α (p = 0.004), IL-6 (p = 0.007) and IL-10 (p = 0.03) levels were increased in childhood-onset SLE patients when compared to first-degree relatives and healthy controls. TNF-α levels were significantly increased in patients with active disease (p = 0.014) and correlated directly with SLEDAI scores (r = 0.39; p = 0.002). IL-12 (p = 0.042) and TNF-α (p = 0.009) levels were significantly increased in patients with nephritis and TNF-α in patients with depression (p = 0.001). No association between cytokine levels and SDI scores or medication was observed.ConclusionTh1 cytokines may play a role in the pathogenesis of neuropsychiatric and renal manifestations in childhood-onset SLE. The correlation with SLEDAI suggests that TNF-α may be a useful biomarker for disease activity in childhood-onset SLE, however longitudinal studies are necessary to determine if increase of this cytokine may predict flares in childhood-onset SLE.  相似文献   

18.
The higher counts or particular groups (Firmicutes/Bacteroidetes) of intestinal microbiota are related to host metabolic reactions, supporting a balance of human ecosystem. We further explored whether intestinal lactobacilli were associated with some principal cellular and metabolic markers of blood in 38 healthy >65-year-old persons. The questionnaire, routine clinical and laboratory data of blood indices as much as the oxidized low-density lipoprotein (ox-LDL) and baseline diene conjugates in low-density lipoprotein (BDC-LDL) of blood sera were explored. The PCR-based intestinal Lactobacillus sp. composition and counts of cultivable lactobacilli (LAB) were tested. The facultative heterofermentative lactobacilli (Lactobacillus casei and Lactobacillus paracasei) were the most frequent (89 and 97%, respectively) species found, while Lactobacillus acidophilus, Lactobacillus plantarum and Lactobacillus reuteri were present in almost half of the elderly persons. The number of species simultaneously colonizing the individuals ranged from 1 to 7 (median 4). In elderly consuming probiotics the LAB counts were significantly higher than in these not consuming (median 7.8, range 4.2–10.8 vs. median 6.3, range 3.3–9.7 log cfu/g; p = 0.005), adjusted (OR = 1.71, CI95 1.04–2.82; p = 0.035) for age and body mass index (BMI). The colonization by L. acidophilus was negatively related (r = ?0.367, p = 0.0275) to L. reuteri, staying significant after adjusting for age, sex and BMI (OR = 0.16, CI95 0.04–0.73; p = 0.018). However, the blood glucose concentration showed a tendency for a negative correlation for colonization with Lactobacillus fermentum (r = ?0.309, p = 0.062) adjusted for BMI (Adj. R2 = 0.181; p = 0.013) but not for age and sex. The higher white blood cells (WBC) count was positively related (r = 0.434, p = 0.007) to presence of Lactobacillus reuteri adjusted for age, sex and BMI (Adj. R2 = 0.193, p = 0.027). The lower values of ox-LDL were predicted by higher counts of cultivable lactobacilli adjusted by sex, age and BMI (r = ?0.389, p = 0.016; Adj. R2 = 0.184 p = 0.029). In conclusion, the pilot study of elderly persons shows that the intestinal lactobacilli are tightly associated with WBC count, blood glucose and content of ox-LDL which all serve as risk markers in pathogenesis of inflammation, metabolic syndrome and cardiovascular disease (CVD).  相似文献   

19.
Alburnus alburnus alborella is a fish species native to northern Italy. It has suffered a very sharp decrease in population over the last 20 years due to human impact. Therefore, it was selected for reintroduction projects. In this research project, support vector machines (SVM) were tested as possible tools for building reliable models of presence/absence of the species. A system of 198 sites located along the rivers of Piedmont in North-Western Italy was investigated. At each site, 19 physical-chemical and environmental variables were measured. We verified that performances did not improve after feature selection but, instead, they slightly decreased (from Correctly Classified Instances [CCI] = 84.34 and Cohen's k [k] = 0.69 to CCI = 82.81 and k = 0.66). However, feature selection is crucial in identifying the relevant features for the presence/absence of the species. We then compared SVMs performances with decision trees (DTs) and artificial neural networks (ANNs) built using the same dataset. SVMs outperformed DTs (CCI = 81.39 and k = 0.63) but not ANNs (CCI = 83.03 and k = 0.66), showing that SVMs and ANNs are the best performing models, proving that their application in freshwater management is more promising than traditional and other machine-learning techniques.  相似文献   

20.
We present the longest high-elevation tree-ring width dataset in the Mediterranean reaching back to the 6th century CE. The network includes 101 living and 92 relict Pinus heldreichii Christ trees from four differently exposed sites in the 2100–2200 m a.s.l. elevation range of Mt. Smolikas in the Pindus Mountains in Greece. Though the sites were all sampled within a distance of <1 km, inter-site correlations are surprisingly low (r1550–2014 = 0.65–0.87), indicating site exposure might affect tree-ring formation. We here explore the consequence of exposure differences on the climate signals in an eastern Mediterranean treeline ecotone. Temporally stable growth/climate relationships reveal similar seasonal patterns among the four sites, but differences in signal strength. P. heldreichii growth at Mt. Smolikas is significantly controlled by temperature in April (r1951–2014 = 0.33–0.50) and precipitation in June-July (r1951–2014 = 0.23–0.42), which emphasizes the overall importance of an early growth onset and subsequent moisture conditions. The association between stem growth and April climate is strongest in the South-facing stand, supporting the significance of higher insolation rates at this thermally privileged site. Strongest summer precipitation signals are found in the NE-facing stand, where trees seem to benefit least from an early growth onset and where reduced meltwater supply may enhance the dependency on early summer precipitation. The significance of spring temperature on tree growth in all four sites constrains the emergence of a distinct summer precipitation signal in the Mt. Smolikas high elevation ecotone. Exploration of the site-specific influences on a new millennium-long tree-ring width dataset is an important step towards an improved understanding of long-term climate variability in the Eastern Mediterranean. Site-related differences in climate sensitivity in the high-elevation tree-ring network at Mt. Smolikas indicate that both temperature and precipitation during different seasons could potentially be reconstructed if distinct site exposures (S versus NE) are considered.  相似文献   

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