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1.
Background: Pathways (footpaths and roads) in forests are associated with edge effects, affecting forest structure and composition and associated wildlife. However, little is known about how edge effects along pathways may impact the dynamics of fruit production and their availability for frugivores.

Aim: We related pathway width as a proxy for edge effects to fruit production. Our underlying hypothesis was that pathway width would be positively related to fruit production.

Methods: We observed fruit production along three pathways of different widths – 2, 10 and 20 m wide – and in a control area of undisturbed forest in an Atlantic rain forest stand monthly over a 2-year period.

Results: The number of species and individuals-bearing fruit was higher along the wider pathways than along the narrowest pathway and in the control area. The amount of zoochorous fruits was higher in the control area than along pathways, and the widest pathway had higher non-zoochorous fruits production. Fruiting peaks occurred along pathways, while fruiting in the control area was aseasonal.

Conclusions: Pathway width is related to fruit type and its quantity and temporal availability. These effects extend towards the forest interior beyond 35 m. The presence of paths affects food resources for frugivores and thus can contribute to reconfiguring the spatio-temporal distribution of the fauna.  相似文献   


2.
Background: Extrapulmonary tuberculosis (EPTB) often presents with nonspecific signs and symptoms. Further the paucibacillary nature of extrapulmonary specimens and irregular distribution of bacilli lower the sensitivity of conventional diagnostic methods making EPTB, a diagnostic dilemma.

Objective: To study neopterin, protein carbonyl and malondialdehyde (MDA) in EPTB.

Methods: Sixty nine clinically confirmed cases with an equal number of age and sex matched healthy controls were enrolled. Ziehl–Neelsen staining for acid fast bacilli and culture on Lowenstein–Jensen medium were performed on all the extrapulmonary specimens. Serum neopterin and protein carbonyl levels were estimated using commercial ELISA kits. Malondialdehyde was determined by measuring thiobarbituric acid reactive substances.

Results: Serum neopterin, protein carbonyl and MDA levels were significantly discriminative for cases of EPTB from healthy controls (p?<?0.05). Levels of all the three biomarkers under study significantly differed between culture as well as smear positive and negative cases. A positive correlation between neopterin and protein carbonyl was seen among the cases.

Conclusions: So far few studies have integrated combination of validated host biomarkers for active disease in EPTB. Our study suggests the potential diagnostic role of neopterin, protein carbonyl and MDA in EPTB.  相似文献   


3.
4.
Background: The dwarf shrub Vaccinium myrtillus – with high cover, height, and fruit production – benefits capercaillie (Tetrao urogallus).

Aims: Our aim was to quantify landscape (e.g. elevation, geographic location, and precipitation), site (e.g. overstorey cover and stoniness) and very fine scale factors (e.g. spatial associations in the understorey) that affect cover, height, and fruit production of V. myrtillus in subalpine forests in thePyrenees, with understorey usually dominated by Rhododendron ferrugineum.

Methods: We sampled 155 plots (0.5 m × 5 m) in six sites. For each plot, in the understorey layer, we assessed species cover, height for R. ferrugineum and V. myrtillus, number of total fruits in V. myrtillus, and spatial associations among V. myrtillus and the remaining cover types.

Results: Overstorey cover negatively influenced V. myrtillus cover, its height, and particularly, the number of fruits, which was also negatively influenced by R. ferrugineum cover. Associations between R. ferrugineum and V. myrtillus were site dependent, while V. myrtillus showed mostly positive associations with grasses and mosses.

Conclusions: Reducing overstorey and R. ferrugineum cover has the strongest positive effect on increasing V. myrtillus fruit production, but with additional positive effects on V. myrtillus cover and height. Increases in grass and moss coverage could favour V. myrtillus.  相似文献   


5.
Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome.

Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.

Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).

Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.  相似文献   


6.
Context: Diabetes is a growing global metabolic epidemic. Current research is focussing on exploring how the biological processes and clinical outcomes of diabetes are related and developing novel biomarkers to measure these relationships, as this can subsequently improve diagnostic, therapeutic and management capacity.

Objective: The objective of this study is to identify the most recent advances in molecular biomarkers of diabetes and directions that warrant further research.

Methods: Using a systematic search strategy, the MEDLINE, CINAHL and OVID MEDLINE databases were canvassed for articles that investigated molecular biomarkers for diabetes. Initial selections were made based on article title, whilst final inclusion was informed by a critical appraisal of the full text of each article.

Results: The systematic search returned 246 records, of which 113 were unique. Following screening, 29 records were included in the final review. Three main research strategies (the development of novel technologies, broad biomarker panels, and targeted approaches) identified a number of potential biomarkers for diabetes including miR-126, C-reactive protein, 2-aminoadipic acid and betatrophin.

Conclusion: The most promising research avenue identified is the detection and quantification of micro RNA. Further, the utilisation of functionalised electrodes as a means to detect biomarker compounds also warrants attention.  相似文献   


7.
Context: Several assays of monitoring immune cell function have been developed to enhance therapeutic drug monitoring.

Objective: An in vitro-validated whole-blood assay of phosphorylated ribosomal protein S6 (pS6RP) was evaluated for confounders to monitor the mTOR-inhibitor everolimus (ERL).

Materials and methods: Whole blood samples from 87 heart transplant recipients were analyzed for pS6RP-expression in CD3-positive T-cells by phospho-flow analysis.

Results: ERL blood concentration, laboratory parameters, co-medications, demographic and clinical data were reviewed.

Conclusion: Evaluating the pS6RP-assay revealed that pS6RP is influenced by cyclosporine A (CsA) blood concentration, duration of ERL treatment, co-medication with thiazide diuretics and different metabolic parameters.  相似文献   


8.
Background: Forests in forest-steppe ecotones are usually highly fragmented and much of the forested area is exposed to climate and land-use-related edge effects.

Aim: To test the hypothesis that the epiphytic lichen diversity at the forest edges was reduced compared with that in the forest interior, and to analyse lichen diversity in comparison with the more highly elevated and more continental Mongolian Altai.

Methods: Six plots each in the interior and the edge with a total of 240 Larix sibirica trees were studied in the Katon-Karagai National Park, East Kazakhstan.

Results: Species richness and evenness at the tree level were higher in the interior than at the edge. The epiphytic lichen diversity in the forest interior was similar in the Kazakh and Mongolian Altai, whereas that at the forest edge was lower in the Mongolian Altai.

Conclusions: Strong degradation of the forest edges in the Kazakh Altai is the probable cause of the reduced epiphytic lichen diversity compared with the interior. The similar species richness in the forest interiors of the Kazakh and Mongolian Altai suggests that the differences at the forest edge are probably, at least partly, due to different land-use regimes and not to differences in macroclimate.  相似文献   


9.
Context: Yes-associated protein (Yap) has been linked to several cardiovascular disorders, but the role of this protein in septic cardiomyocytes is not fully understood.

Objective: The aim of our study was to explore the influence of Yap in septic cardiomyopathy in vivo and in vitro.

Materials and methods: In the current study, Yap transgenic mice and Yap adenovirus-mediated gain-of-function assays were used in an LPS-established septic cardiomyopathy model. Mitochondrial function and mitochondrial fission were determined through western blotting, immunofluorescence analysis and ELISA.

Results: Our results demonstrated that Yap expression was downregulated by LPS, whereas Yap overexpression sustained cardiac function and attenuated cardiomyocyte death. The functional exploration revealed that LPS treatment induced cardiomyocyte mitochondrial stress, as manifested by mitochondrial superoxide overproduction, cardiomyocyte ATP deprivation, and caspase-9 apoptosis activation. Furthermore, we demonstrated that LPS-mediated mitochondrial damage was controlled by mitochondrial fission. However, Yap overexpression reduced mitochondrial fission and therefore improved mitochondrial function. A molecular investigation revealed that Yap overexpression inhibited mitochondrial fission by reversing ERK activity, and the inhibition of the ERK pathway promoted DRP1 upregulation and thereby mediated mitochondrial fission activation in the presence of Yap overexpression.

Conclusions: Overall, our results suggest that the cause of septic cardiomyopathy appears to be connected with Yap downregulation. The overexpression of Yap can attenuate myocardial inflammation injury through the reduction of DRP1-related mitochondrial fission in an ERK pathway activation-dependent manner.  相似文献   


10.
Context: Soluble CD40 ligand (sCD40l) can predict cardiovascular events (CVE) and mortality in haemodialysis (HD) patients (short-, medium-term follow-up studies).

Objective: To evaluate the relationship between sCD40l and survival, CVE and mortality in HD patients on long-term follow-up.

Methods: We registered 46?HD patients’ baseline characteristics, mortality and CVE for 108 months.

Results: SCD40l correlated positively with C-reactive protein, was higher in survivors, but had no impact on survival and was not predictive for CVE or CV mortality.

Conclusion: The levels of sCD40l have no influence on survival or CVE and mortality in HD patients in a long-term follow-up.  相似文献   


11.
Context: Genetics play a major role in development and pathophysiology of Type 2 diabetes mellitus (T2DM).

Objective: To asses the association of Guanine nucleotide-binding protein (GNB3) (C825T) gene's polymorphism with T2DM.

Materials and methods: A case–control study including 400 North Indians was performed using Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) approach to analyze genetic polymorphism.

Results: No significant difference was observed in genotype and allele frequencies of GNB3 gene on comparing cases with controls.

Discussion: Our study is in agreement with studies on Polish, Japanese, Hispanic-American and Danish populations who observed no significant association between GNB3 (C825T) polymorphism and T2DM.

Conclusion: GNB3 (C825T) polymorphism is not associated with T2DM.  相似文献   


12.
Capsule All British Marsh Tits belong to subspecies Poecile palustris dresseri, being smaller than nominate P. p. palustris of central Europe.

Aims Determining the subspecies of Marsh Tit in Britain to test whether ssp. P. p. palustris occurs in northern England and Scotland, by assessing regional variation in size compared with central European birds.

Methods 1147 wing length and 250 tail length measurements from 953 Marsh Tits were compared between eight British locations to test for regional variation. Biometrics were compared between birds from Britain and six locations within the continental European range of ssp. palustris.

Results There was no regional variation in wing or tail lengths among British Marsh Tits, indicating that all resident birds belong to ssp. dresseri. There was no evidence supporting the existence of ssp. palustris in northern England. British birds were significantly smaller than those from continental Europe, with proportionately shorter tails, consistent across all age and sex classes.

Conclusion All British Marsh Tits should be considered as ssp. dresseri, with ssp. palustris being limited to continental Europe. With no evidence of regional variation in size within Britain, reliable sexing methods based on biometrics could be applied in demographic studies throughout the country.  相似文献   


13.
Context: Various processes including inflammation and endothelial dysfunction have been implicated in the pathogenesis of cardioembolic (CE) strokes.

Objective: To review the evidence and investigate the association between immune-inflammatory biomarkers and CE strokes versus other stroke subtypes.

Methods: We systematically reviewed the literature (sources: MEDLINE, web-based register http://stroke-biomarkers.com, reference lists) with quality assessment and meta-analysis of selected articles.

Results: The most consistent association was found between C-reactive protein (CRP) and CE strokes when compared to other stroke subtypes (standardized mean difference 0.223 (0.116, 0.343); p?<?0.001)

Conclusions: Our findings confirm a possible association between selected inflammatory biomarkers and CE stroke.  相似文献   


14.
Background: It has been reported that some plants of the self-compatible species Senecio vulgaris produce capitula containing long-styled florets which fail to set seed when left to self-pollinate, although readily set seed when self-pollinated by hand.

Aims: To determine if production of long-styled florets is associated with higher outcrossing rate in S. vulgaris, and whether long-styles occur in non-pollinated florets, whereas short-styles are present in self-pollinated florets.

Methods: The frequency of long-styled florets was compared in the radiate and non-radiate variants of S. vulgaris, known to exhibit higher and lower outcrossing rates, respectively. In addition, style length was compared in emasculated florets that were either self-pollinated or left non-pollinated.

Results: Long-styled florets were more frequent in the higher outcrossing radiate variant. Following emasculation, long styles occurred in non-pollinated florets, while short styles were present in self-pollinated florets. The two variants did not differ in style length within the non-pollinated or within the self-pollinated floret categories.

Conclusions: A high frequency of long-styled florets is associated with higher outcrossing rate in S. vulgaris and results from delayed self-pollination and pollen germination on stigmas.  相似文献   


15.
Capsule: Nestling Southern Grey Shrikes Lanius meridionalis show a high prevalence of haemosporidian parasites including five lineages described here for the first time.

Aims: To examine the prevalence of various haemosporidian lineages in nestlings of three separated Iberian populations of the Southern Grey Shrike.

Methods: Blood samples were taken from nestling Southern Grey Shrikes from three agroecosystem areas in the Iberian Peninsula. Parasites were detected from blood samples using polymerase chain reaction screening.

Resusts: Nestlings were parasitized by 11 different lineages belonging to the genera Haemoproteus (3.8%), Plasmodium (0.5%) and Leucocytozoon (1.8%), including five new undescribed lineages. These are among the highest prevalence levels of haemosporidians parasites (7.4%) for nestlings of passerine birds.

Conclusion: Our findings suggest that the distribution of avian haemosporidians is determined by complex effects including climate and biogeography. Most parasite lineages were not universally spread across shrike populations, despite being otherwise widespread both geographically and taxonomically.  相似文献   


16.
Context: Leptin is produced in white adipose tissue, but also in human coronary atherosclerotic lesions.

Objective: The aim of this study is to assess the prognostic value of leptin in patients with proven coronary artery disease (CAD) (N?=?1907).

Methods: AtheroGene is a contemporary CAD cohort study (N?=?3229). Median follow-up time was 3.8 (Quartile 1/3 with 2.8/4.9) years.

Results: Leptin concentration was associated with a hazard ratio (HR) for the fully adjusted model of HR?=?1.32 in women but was not significant in men. The endpoint cardiovascular death and non-fatal myocardial infarction was observed in 167 patients.

Conclusion: In women with known CAD, increased leptin concentration is useful for predicting cardiovascular death and non-fatal myocardial infarction.  相似文献   


17.
18.
Context: Sepsis is now the leading cause of death in the noncardiovascular intensive care unit (ICU).

Objective: To investigate whether polymorphisms in IL21 gene contribute to sepsis susceptibility.

Materials and methods: Three single-nucleotide polymorphisms of IL21 (rs907715, rs2055979, rs12508721) were genotyped by TaqMan assay in patients with sepsis and control subjects.

Results: Polymorphisms rs2055979 and rs12508721 in IL21 were more frequent in sepsis patients compared to general population. But allele frequency of rs907715 was not significantly different between sepsis patients and control subjects.

Conclusion: Polymorphisms in IL21 may be associated with sepsis risk.  相似文献   


19.
Context: Carboxymethyl-lysine (CML) results from oxidative stress and has been linked to cardiovascular disease.

Objective: The objective of this study is to investigate the association between sleep-disordered breathing (SDB) – a source of oxidative stress – and CML.

Materials and methods: About 1002 participants in the Cardiovascular Health Study (CHS) were studied.

Results: Women with SDB had significantly higher CML concentration compared with those without SDB (OR?=?1.63, 95%CI?=?1.03–2.58, p?=?0.04). The association was not significant among men.

Discussion: SDB was associated with CML concentration among elderly women but not men in the Cardiovascular Health Study.

Conclusion: Accumulation of CML may be an adverse health consequence of SDB  相似文献   


20.
Background: Flower colour variation among populations may result from the spatial variation of selective agents. The structure of phenotypic variation informs on the ecological processes related to this variation. Variation in floral traits is mainly attributed to variation in the pollinator fauna, while variation in vegetative traits is usually linked to abiotic factors or herbivores.

Aims: We investigated the geographical variation of flower colour (and correlated traits) in Gentiana lutea and the relationship with the variation in abiotic factors.

Methods: Phenotypic variation (flower colour, petal length, petal width, stalk length, leaf length, flower number, petal number and number of basal leaves) was assessed in 429 plants of 12 populations located at north-west Iberia. Additionally, we obtained data on the geographical coordinates, elevation, temperature, rainfall and radiation for each population.

Results: Populations mostly differed in flower colour, from orange to yellow from west to the east. Abiotic factors were unrelated to variation in either floral or vegetative traits.

Conclusions: Phenotypic variation among G. lutea populations does not result from adaptation to environmental factors. Other factors, such as historical events or selective pressure exerted by biotic interactions, might explain the flower colour variation in G. lutea along the Cantabrian Range.  相似文献   


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